Overheating......Radiator Fan Not running... Help

Great forum...by the way!!

93 Ply Grand Voyager SE 3.3L V6
Drove about 10 miles yesterday van ran fine. Stopped in a parking lot left van running. Check gauge light came on. Van was overheating. Coolant level was fine. Radiator fan would not run. Drove it back home temperature gauge stayed were it always did on drive home. Left it running in driveway it began to overheat. Checked fan it is operational just won't kick on.

Any advice???

A/C compressor stopped running a couple weeks ago could they be related problems? Relays Prehaps??

I am having the same issues and I can not figure it out.

I replaced the thermostat.
I tried to replace the fan, thinking it was bad, recieved the same results so I took the $200 fan back.

Now I am going to try to replace the sensor.

At least I am not alone. If we could just figure out the problem.

To bring you up to date on mine: we bought a new coolant temperature sensor and tried it, but it did not solve the problem.

We were stumped so we ran a wire from radiator fan to battery. Fan would kick in and we could watch the temperature gauge drop as fan ran.

Since we didn't know what to do next we improvised. We spliced radiator fan wire, ran that to battery, then to a toggle switch inside van.
I've drove with it for about a week now. As long as I am driving the temp gauge is fine. When I am idleing I keep an eye on gauge if it starts to rise I flip the toggle switch for the fan. So far this has worked great. I just have to remember to flip it off. Although a more permanent solution would be better. If you find out anything please pass it on, as will I.

Someone suggested the radiator fan relay. I checked on one it runs $24.99 So if I have the extra cash I will try it this weekend. If not next.

Keep me posted on your progress. :smile:

:banghead:
Well, I spent $13 dollars for the sensor and as you know, this did not work. I did buy a book called "sure you can" "work on electronic ignition"
Its by a company called Wells. You purchase a key that you can supposedly plug into a spot to get all of the service codes for your car. This should give me a better ballpark as to what is wrong with my car. I will try it and keep everyone posted.

My major problem is I dont know where to plug the d@#! thing in.

I am having the same problem with a 93 with the 3.3
I changed the fan, changed both relays, temp sensor, etc...

I ran a switch to the dash board to turn the fan on and off as needed.

I just orded a universal temp sensor from Jegs (16.99).

When it comes in I will mount it and use a realy to turn the fan on and off. The temp sensor is rated at 170f.

I will keep you posted.

Oh yea I also stoped by a Chrysler dealer and asked him about it and he was lost on why it did not work but for $85.00 per hour they would look at it. No thanks!

As many of you know by now is that the cooling fan is not just a simple circuit.

First the fan is a 2 speed fan, low and high (I don't know why)

Low is for normal cooling of the radator.

High is for when the a/c is on, or the transmison calls for high cooling ( why the trans is any ones guess)

So there are 2 relays, low and high, and somewhere else there is a fan switch.

The fan switch is mounted unknow by me or the 3 places I went to.

The fan has 4 wires on it. Ground, low, high, and unknow.

The unkown wire might be a feedback wire.

As far as I can tell the temp sensor tells the temp gauge what the temp is and also tells the power train controll what temp the engine is at.

At that point the power train controll will either select low or high.

I have taken 2 fans and applied 12 volts to the low and the fan did not spin at all. If I put 12 volts on the high the fan runs.

If I put 12 volts on that yellow wire I get sparks.

Why did chrylser make a simple fan so complacted I do not know.

All this about the fan I figured out myself, if I am wrong on how it works please correct me.

I have spent many hours working on this fan curcuit and many phone calls to the local dealer ( that was little help at all ).

I have had other cars that the fan stoped working and they were no where this complated.

So for know I am using a toggle switch for the fan. I did order a temp sensor and will hook that up for the fan using a relay. A simple circiut using just the high speed and nothing else, just the way it should be.

Thanks
John

So for know I am using a toggle switch for the fan. I did order a temp sensor and will hook that up for the fan using a relay. A simple circiut using just the high speed and nothing else, just the way it should be.

Thanks
John[/QUOTE]

Hey John,

Which wire to the fan did you use to get your fan to turn on and what was the wire flow to use a togle switch?

Thankks
Magus

I went to Autozone and got some red wire (10 gauge) and a 30 amp fuse.

I ran the 2 runs of wire through the fire wall (down near the bottom you will see a gromet with a thick black cable for the hood release)

One wire from the positive post on the battery to the switch to a toggle switch back to the fan.

I tapped into the green wire (I don't remember if it was the light green or dark green) but it is the high speed on the fan.

The toggle switch I used is rated for 30 amps same as the fuse I used.

I did not measure the current for the fan, I would guess it would be around 20 amps since the wire chrysler uses is a heavy gauge.

Did anyone check the radiator fan fuse (link?). My daughter had a major overheating episode, and the mechanic said he had to replace the fuse -- don't know if this was a cause (probably) or result of the overheating.

changed both relays

Hey Bigjohnjr, I am having the same problem (started another thread without seeing this one).

My big question to you: where ARE the relays for the fan circuit located? I have a 98 Caravan, and I tried to trace the cables back from the fan modules, but do not see a relay in-line. The relays in the fuse/relay box do do not seem to indicate one is for the radiator fans:

CIG & ACCY
FRONT WIPER HI/LO
FRONT WIPER ON
HI BEAM
LOW BEAM
HORN
A/C CLUTCH
BLOWER MOTOR
STARTER
PARK LAMP
EATX SHUTDOWN
FUEL PUMP
AUTO SHUTDOWN

Is one of those ALSO for the radiator fans? At first I though the "BLOWER MOTOR" might be that, but it is for the AC fan, right?

Thanks for your help!

Vickers

There are 2 relays.

1 for high speed and 1 for low speed

They are mounted on the inner fender drivers side.

I think that are 4 or 5 relays in a row.

The 2 fan relays are NOT side by side.

I do not know what the other relays do.

The reason that there are relays is because the fan draws about 20 amps.

The blower motor is the fan for your heat/defrost/ac.

There are 4 wires on the fan, like I posted before. The 2 green wires are the +12 volt.

Light green and dark green
Black is ground
Yellow is unknown, might be a feedback for the computer.

OK ALL FIXED!!!!!!!!!!!!!!

I got my temp sensor today from Jegs.

Attached to the upper radiator next to the thermastat.

Ran the wires for it along the firewall into the van, under the dash I wired it to a relay, hooked up the relay to the fan.

Ran the van, it got hot, fan came on, temp went down, fan turned off.

Simple.

All, Great thread.

I have the same problem mentioned above.
Fan not coming on. Tested fan straight to battery ok.
Manual states that good fan should run when temp sensor is unplugged
if bad sensor. Does this sound right? Did not work for me.
Am looking at the relays next? There are 4 on driver side fender panel.
Anyone know which are for fan? Have seen posting on high and low speed reply? Would fan work on just one good relay?

I also noticed that when overheating occurs the overfill bottle fills up.
Is this an issue? I did not know if the temp sensor is behind the
thermostat and the thermostat does not open whould this cause
the sensor to seem bad not allowing fan to run?
What other things would indicate a bad thermostat?

Thanks for any help,

If you short the sensor wire to ground the fan should come on, or if you turn on the A/C.

If the fan does not turn on you have the same problem that we all have.

When the bottle overflows is because the coolent is too hot, it is boiling and then turns to steam and the presssure builds and wants to leave the system.

By cooling the coolent it does not boil over.

I do not at this time remeber what relay turns on the fan for the low speed but it has a green wire and a gray wire on it.

Just like the high speed it has a green and gray.

I do not remember if it is light green or dark.

Your problem most likley is not a bad thermastat.
The fan would still come on, bad thermastat and all.

Update on my end, I added another relay to turn the fan on when the a/c is on. I did not have to, I just wanted it to turn on whenever the a/c is on. Just like it use to.

If you need anymore help let me know.

John

John, The grounding of the sensor wire did not get the fan going.
I guess the sensor could still be good? I am a bit confused by the
high speed low speed thing. I know I have 2 fans. The one on the passengers side is for the A/C. It comes on when the A/C inside is on and the blower on high. The Fan on the radiator is the problem.

My Hayes book shows the 4 relays. If I am reading it right the the third one in from the front of van as the Radiator fan relay.
Does this sound right?

I am courious about your fix. How exactly did you mount the Jeg's
sensor? I could not find a universal temp sensor on Jegs web site. Does it replace the original? Did you run the wiring from the fan
motor to the sensor then to the relay? Did you use the same type of
relay as the original? How does the fuse fit in?
I hope this is not too many questions but I just hate to have to take
it to the shop and start getting the run around or over charged for
something I could take care of. I have done a bit of work on this
93 3.3 AWD Grand Voyager. Replaced starter, water pump, o2 sensor,
radio replacement. I am not very knowledgable on electrical things though.

Have you ever done the 'code' thing? I get a 34 I think this has been on there for a while and unrelated. When I had the temp sensor unplugged I got a 22. Coolant sensor voltage too high or too low.
Never got a 35 Radiator fan relay circuit problem.

It is really great to read other peoples experiences. You all have helped
just sharing the info!! I really like my van and hope to keep it until I can afford a Hemi Ram Pickup. I just dread the day that I can no longer keep up with the technology for minor problems.

Thanks again.
Mike

Ok first of all, my van has 1 fan.
The fan has 4 wires.

The temp sensor is connected to the temp gauge.

My van has only 2 relays. High speed and low speed.

The part number for the sensor is 077119003 170 degree sensor and it cost 16.99

It attaches on the upper radator hose, it straps around it, then I wired it to a NEW relay and then to relay to the fan.

It is really simple to hook up. With the sensor from jegs they give a simple diagram on how to hook it up.

I did use a fuse, I used a 30amp.

You NEED a relay! The fan draws way to much current for the sensor to handle. You can be a relay at any local auto store or from Jegs if you wish.

If I were you I would be the senors and get a relay and fix it so it does not boil over, over heating is really bad for the engine.

John, I ordered the Jegs Perma-Cool Fan wiring kit $17.99
It comes with the 170 degree Sensor, fuse and wiring.
I also ordered the Perma-Cool A/C Relay $7.99.
They say you need it for a 2 fan system. We'll see how it all ties
together on their instructions. The bummer is that living in Alaska
the shipping and handling is more than the parts!
Still better than taking it to a shop I think.
Thanks for all the help!! I will let you know how it goes.


Thanks again!!! Mike

When my van first broke down (overheated when stuck in traffic) I had the van towed to a garage and the person there told me that the fan was bad he gave me price of $379.00 for the fan plus labor.

I drove the van home, hoping not to get stuck in traffic again, I went to a local junk yard and got another fan for $100.00.

I put it in and I thought that was it, all done.

I let the van run and it over heated again, thats when I went and checked everything out.

I never would have thought that so many people have the same problem.

Not just here but also at my job, 2 people have the same problem, one is a 91 and the other is a 92.

This must be common problem for these vans, another poor design by chrysler.

Why make simple fan such a completed circuit?

It does not have to be that way, as I have proven. A simple temp sensor and a relay. It just works. The coolant gets hot and the temp sensor conducts, pulls in the relay, fan comes on.

No need for high speed and a low speed.

One more relay connected to the a/c clutch to turn on the fan when the a/c unit is on.

I got the Jegs order in today. I had a little problem figuring out how my van needed to be hooked up. I did not use the Diagram B but used Diagram C without the Relay for the A/C Clutch, mine has a seperate relay for that. The downside for this hookup is that once the van is turned off, the fan can still run until the temp is below 170. The first time it only ran for maybe 3-4 minutes. I don't know what kind of strain this puts on the battery as of yet. I think the battery end of the hook up can be routed with the ignition so it can turn off the power to the fan insted of waiting on the sensor. I will be looking into that.
All I can say is thanks to BigJohnJR.!! This fixed cost aprox $55 dollars!
50% of that was shipping up here to Alaska! I don't even want to know what a shop would have charged to fix it!
I have liked my 92 AWD 3.3 Grand Voyager since I have owned
it. I had to have a new transmission put in at around 30,000. Thank-you
extended warranty! New struts, 2 starters, waterpump and this issue.
The transmission has a clunk in it sometimes. I am worried about this
in the long term. Other owners I know have it also. I guess I have been pretty lucky. Thanks again BigJohnJR!!!

I am going to be a regular at this web site to see what else I can learn and hopefully share. Mike

Congrats on the install!

I still do not understand why they made a simple thing like a cooling fan so complicated.

It does not have to be that way.

Mine fan shuts off when I turn off the van, I did not want to kill the battery.

John

John, The grounding of the sensor wire did not get the fan going.
I guess the sensor could still be good? I am a bit confused by the
high speed low speed thing. I know I have 2 fans. The one on the passengers side is for the A/C. It comes on when the A/C inside is on and the blower on high. The Fan on the radiator is the problem.

My Hayes book shows the 4 relays. If I am reading it right the the third one in from the front of van as the Radiator fan relay.
Does this sound right?

I am courious about your fix. How exactly did you mount the Jeg's
sensor? I could not find a universal temp sensor on Jegs web site. Does it replace the original? Did you run the wiring from the fan
motor to the sensor then to the relay? Did you use the same type of
relay as the original? How does the fuse fit in?
I hope this is not too many questions but I just hate to have to take
it to the shop and start getting the run around or over charged for
something I could take care of. I have done a bit of work on this
93 3.3 AWD Grand Voyager. Replaced starter, water pump, o2 sensor,
radio replacement. I am not very knowledgable on electrical things though.

Have you ever done the 'code' thing? I get a 34 I think this has been on there for a while and unrelated. When I had the temp sensor unplugged I got a 22. Coolant sensor voltage too high or too low.
Never got a 35 Radiator fan relay circuit problem.

It is really great to read other peoples experiences. You all have helped
just sharing the info!! I really like my van and hope to keep it until I can afford a Hemi Ram Pickup. I just dread the day that I can no longer keep up with the technology for minor problems.

Thanks again.
Mike
its the engine control modual drivers side fender wall it controls everything to do with the engine and cooling when you turn on the ac it tells the computer to turn the fan on when the temp gets high your cooling sen tells the computer to kick the fan on so your sencer is good your relays are good so your computer is getting the message but isnt turning the fan on you could get a computer a junk yard for about fifty bucks but make sure its the right on their is a 7 didgit number on it make sure it matches the new one thy have a hole bunch of difrent ones a new one at advance is about 250 bucks

Yes that is true, you can change the engine control modual. I tried to find one at the local junkyard and was told he wanted $200.00 for it.

For $25.00 I added a new temp sensor and it works perfect.

Either way works.

John

i think Whitney may have the answer. i just got the same problem this includes the following symtoms... over heating, resevoir overflowing, radiator fan quit, shortly after this in a period of two days the A/C quit. contacted a very close friend and mechanic, he said" check for fusible link by the starter. i didn't find one by the starter but after following the power wire(check to ground to see which this is) not the ground wire up the harness where it went to relay and changed colors and then under driver side hood hinge found wire changed to a very small 20 guage wire and orange. this wire was burned and after doing a temporary jump found it was the problem. still need to replace this with a lead and a fuse. this wire looks odd and i'm not sure how this small wire can carry the amps that the fan needs cuz it is so small. radiator fan works and A/C came back on immediately. cost of repair? 10 cents worth of wire, 2- 5 cent butt splices and 45 mins time. i love my mechanic. 92 dodge caravan 3.3

stupid server this isn't the thread i was in.

on your 98 you have a fan relay on the bottom right as you stand in front of your car. it is below your cooling fans they run in my area about 80 dollars or check your local junk yard. also the relay may need new screws it is an update from chrysler for remounting this relay in a different spot on the inner driver side frame.. good luk kelly

on your 98 you have a fan relay on the bottom right as you stand in front of your car. it is below your cooling fans they run in my area about 80 dollars or check your local junk yard. also the relay may need new screws it is an update from chrysler for remounting this relay in a different spot on the inner driver side frame.. good luk kelly

We had to pay someone to put a new fuel pump in our van. While they did that we asked if they could fix the A/C and the Fan they found that a Fuseable link went bad so now everything is workin.

We had to pay someone to put a new fuel pump in our van. While they did that we asked if they could fix the A/C and the Fan they found that a Fuseable link went bad so now everything is workin.

Where might this fuse be on a 94 Grand Voyager 3.8L. I'm in the same boat as everyone above. I've done the fan rewire on other vehicles, but I would like to keep the wifes car stock. And if it turns out to be just a fuse...
Already replaced the fan and bought a temp sensor, But not installed yet. I would like to return the sensor or get the right one, if I could find the fuse you guys are talking about.

Thanks for your help.

BTW, It's damn hot here in Phoenix, so I have to fix this pronto!

Thanks again...

On our van the fusible links were on the driver side under the hood they ran along the fender . If they are not there on your van maybe take it up to auto zone if yall have one and they should be able to pull it up and even show you.

My daughters car, a 1997 Dodge caravan, cooling fan wasn't running.
The Service engine light was on with a 35 code. This code points to an open or short in the cooling fan curcuit.
I replaced the Cooling fan relay, located on the drivers side frame member by the radiator. Has a 4 wire plug. Its an elecronic relay/switch.
Napa carries the part but was out of stock, they wanted about $60.00. Got it from the local Dodge dealer for about $70.00. It was special order from Autozone.
The part fixed the problem.

My 94 Plymouth Voyager (4 cylinder) temperature occationally indicates overheating condition, maybe on 1 out of 10 trips. Most trips ,25 miles or so, are without event, but sometimes after 5-10 minutes or so the temperature gauge pegs and the gong goes off. After 1-2 minutes the temperature gauge returns to normal and doesn't indicate overheating the rest of the trip.

So far, this is what I've found out and what I've done to resolve the problem. I've discovered 2 sensors that are involved.

There is a temperature sensor, ACDelco part # C1860, located on the lower portion of the block just below the second spark plug. This part is about 2" long and has a single screw terminal at the top with a single wire connector which can be pulled off. Cost $13.99
See http://www.acdelco.com/html/catalog/index.htm
This sensor drives the temperature gauge and does NOT drive the fan. The wire, when grounded , will peg the temperature gauge but the fan does not come on.

The second is a coolant sensor, Mopar # 33004281, located just below the thermostat behind the igrition coil. This part is also about 2" long but has a locking device on a 2 wire connector. Cost $58 at dealer and $14.95 on Web. See http://www.xtremeterrain.com/p90.htm
This sensor drives the fan via the relay circuitry. When this connector is unplugged, the low speed fan runs, although the check engine light show code #22, coolant sensor "out of range or disconnected". I don't believe this is a problem but looking for comments.

As a side issue, the relays are located in a box on the driver's side wheel well under the hook. The "box" is about 3" by 4" with a locking tab. On the inside cover is shown the relay identification and fuse location. When looking from the front of the van and directly over the computer box, there are 2 columns of relays, the left has 4 relays and the right has 2. The radiator low fan has a 25 amp fuse.

Computer, Relay and Fuse Box

----------------------------------------------------------
|
| FUSES including 25 amp low radiator fan fuse
|
| High Fan Radiator Ground Relay
| Fuel Pump Relay
| Low Fan Radiator Relay Air Cond Clutch Relay
| Auto shut down Relay High Fan Radiator Relay
|
|-----------------------------------------------------------

Front of Van


At this point I'm operating with the temperature sensor connected, (temperature gauge operational) and coolant sensor connector unplugged which causes the low fan to run when the engine is running and living with the check engine light, code #22. This is a cheap fix and may indicate a bad coolant sensor, and I need to replace it. If the overheating reocurrs, I'm planning on looking at the temperature circuit for bad temperature sensor or bad temp gauge. Comments?

I have a 97 T&C with 3.8 AWD and had the same problem. I changed the thermostar (easiest first) no help, I removed the fan abd tested it with direct current worked fine, then I changed a sensor no help, then I had to do a head stand and grow another hand to change a relay on the front of the engine compartment at the side of the radiator, WALLA! Got the sensor from the Chrysler dealer and just a simple plug in for electric change over. Don't know if this helps but it took me about 2 weeks to find the **** relay next to the radiator.

Great forum...by the way!!

93 Ply Grand Voyager SE 3.3L V6
Drove about 10 miles yesterday van ran fine. Stopped in a parking lot left van running. Check gauge light came on. Van was overheating. Coolant level was fine. Radiator fan would not run. Drove it back home temperature gauge stayed were it always did on drive home. Left it running in driveway it began to overheat. Checked fan it is operational just won't kick on.

Any advice???

A/C compressor stopped running a couple weeks ago could they be related problems? Relays Prehaps??


There is a sensor located (on 1997) on the drivers side down by the radiator. It is hard to find, but just follow the wires that are next to hte radiator. This sensor is about 60 bucks but usually is the cause of the problem.

:smile: My cooling fan stopped working in my 96 Caravan awhile back. Took it to the dealer and guess what, there was a recall on a faulty fan control relay. They fixed it (no charge) and never had the problem again.

I'm having the same problem too.. (96 3.3 Caravan) Rad fan isn't kicking on when temp rises. I already replaced the thermastat so I'm guessing it's the temp sensor Bigjohnjr replaced. I did unplug my A/C compressor as even though I had it off and I wanted heat the compressor "seemed" to be still running. (is that normal?)

I have a 97 caravan and the fans stopped working.I looked for the relay and could not find one .after many tries,I found out it uses a solid state relay which is a small square on the inner fender and that fixed the problem. cost of relay $56.00 and it does not look anything like your typical relay. Hope this helps someone out there.

would you happen to have a part number for that relay? or a better description so when I call my parts people they know what I'm talking about.

thxs :)

My 1997 Grand Caravan had the same problem. I replaced a solid state fan relay that cost about $70. it was located near the radiator on the
drivers side below the battery etc.

Spit

I do not remember where I left the receipt, but I just asked the guy @ the counter(bumper to bumper ) and he ordered me one.
you can also call a dodge dealer and ask them for the part numer or better yet go there and they will pull a pcture of the relay and its location so you can see it(it is located on the inside wall bellow the battery and next to the bottom of the radiator,,,it is square and the wires dead end there with another harness going to yhe fan wiring harness.you wont miss it if you just follow the wires from the fans.
Good luck and let me know if that helped.

I bought an 89 Voyager that was overheating because the fan wouldn't kick in. I checked the fan motor, coolant sensor, and relays and found that they were all good.

Then I noticed the fusible link was burnt out so I replaced it (not as easy as it sounds). It immediately started to heat up again with the van running.

I traced the wires to the AC fan and found that it was loose on the shaft due to wear. Went to a junk yard and bought a good used one and it FIXED THE PROBLEM.

What a lousy circuit design! An accessory component goes and it disables your vehicle and can burn up your engine.

Anyone who hardwired their fans....

What did you use as the power source? Where is there a switched power wire?

Thanks

Have a '96 Grand Caravan that had the same problem before - the fan will not kick in and it overheats. I replaced the fan sensor and it solved the problem. A few months after, Dodge came out with a safety recall for the sensors and I got my money back for the parts that I purchased prior to the recall.

Correction - it was a fan relay and not a sensor located underneath the fender wall and radiator.

Hi,

Hope I've not missed any relevant posts on this. My problem similar to what I've read. Make and model 1997 Chrysler LHS, 3.5 Liter engine; two fans; two speeds (two relays in module on L.H. side on fender).

Overheats when not at highway speed (stop-and-go or idle). Have confirmed that fans eventually cut-in, but too late to cool engine to proper level. Used to be intermittent, but now pretty consistent.

Have traced as follows:

Replaced relays.
Shorted lo-speed relay primary to ground - both fans run at lo-speed.
Shorted hi-speed relay primary to ground - both fans run at hi-speed.
Traced wire connection from computer module to both relay primaries - both good.
Traced wire connection to engine coolant temp sensor - good.

My chrysler FSM (Factory Service Manual) for this car indicates that Temp Sensor signal controls both temp guage on dash AND cooling fan operation. Since guage shows a rise in engine temp, should also turn on fans I would think (but doesn't). This is why I haven't replaced coolant temp guage.

Dealer just wants to sell me diagnostic time and then talks all the usual BS (flush the system; change the thermostat; etc. etc.) I KNOW the fans are the problem not the cooling system!

Am thinking of wiring toggle switch on dash to short relay return line to ground but that's just my frustration showing. I'm hoping SOMEBODY knows a LOGICAL explanation.

-Hank

There's really not a whole bunch in that circuit. PCM monitors the engine temp with voltage readings from the coolant temp sensor. I's the PCM's job to select fan function based on engine temp.

I would replace the sender/sensor and check the ground for the radiator fan assembly. Some vehicles have 2 sensors...one for the fan and one for the computer/gauge...I'm not sure if yours is set up that way?
The sender works on variable resistence(temperature dependent), this provides a varying voltage to the PCM which it uses to control the fan and the rest of the engine.

Do the fans go on when you turn the A/C on?

Hi,

You have to really search in the FSM to find anything. (It's like they don't really want to tell you anything!) Anyhoo, you are right, the circuit does seem pretty straight-forward. When I said "guage" I meant to say engine "sensor" (or sending unit). Maybe I will replace it as you suggest. :frown:

BTW the fans run without hesitation when they get the right signal so I'm thinking fan grounds are not an issue. As to the A/C, I looked at that. On GM vehicles the fans cut in as soon as you turn on the A/C. Doesn't seem to be the case on Chryslers according to the FSM. I did notice that the fans did cut in just a little sooner (but still not soon enough) with the A/C running.

Don't know about a "second sensor". Doesn't seem to be one if I read my manual correctly. I'd almost suspect my PCM if it wasn't for the fact that it was replaced about 1½ years ago for another problem and this thing's been going on intermittently for much longer than that.

Ah well, a new sensor it is I guess... Unless there is a second sensor...

-Hank :uhoh:

We had the same thing happen two years ago on our 98. Finally took it to dealer, and they found the relay switch that turns on the fan was broken

Thank you for the heads-up. However, both relays (Hi & Lo speed) have been replaced. The fans do come on but just not soon enough to cool engine to desired temp. See my earlier posts below.:frown:

Overheating solved!! :)

This is for Stevo2 and anyone else interested.

Managed to fix the overheating problem on my 1997 LHS. In desperation, I replaced the coolant temp sensor (about $30.) and wouldn't you know it, the fans started cutting in again exactly the way they're supposed to.

I'm happy the problem is fixed at last but it does leave me wondering. What controls the guage on the dash??? I'm also a little annoyed! You would think this problem has occurred before to somebody somewhere yet nobody, not even the local dealer, could tell me that I could ignore the guage issue and that the problem was in the sending unit on the engine. Would have saved me a lot time barking up the wrong tree. BTW there was no code set in the computer for this.

Anyhoo... there it is. Hopefully this saves somebody else's bacon.

Happy with my LHS again!

-Hank :)