04 Rendezvous Intermittent No Crank Issue

Hello AF community it has been awhile since I have been back here. I'm glad this forum is still up it is always the first website I think of for car issues. I remember there used to be a live chat window as well.

Anyways my mother's Rendezvous has an intermittent no crank issue when the key is turned to start position. Battery is good, starter is good I just replaced it. However the old starter doesn't crank when bench tested. The ignition wire which is a yellow wire lights up when key is turned to start so that tells me the ignition is sending signal. I can get the engine to crank/start when I bypass the crank relay with a jumper wire. I have swapped the original relay with another relay of the same number and still no crank. So this is leading me to either the NSS Nuetral Safety Switch, which the repair manual says it is on top of the transmission even though I can't find it for the life of me but I have also read that the NSS is located inside the tranny which I hope that is not the case.

One thing I would like to note is the fuse block housing in engine compartment was kind of loose when this issue started. Before when the car didn't start I would tell my mother to just wiggle the housing and it would work but that no longer works anymore. I hope I don't have to get under that housing and check all those connections. Thanks a bunch

PS: slot 30 on relay circuit had power the other slot which I forget the number atm had power as well.

Unfortunately NSS is internal. Try shifting to N to start.

For reals? When I look the at component locations for switches one repair manual says on top of transaxle with no pic and then Alldata says it is on top of tranny but the picture they show is not the same as the one I have because it would be noticeable.

If that is the case then maybe I can find the wire some where and test the NSS that way to avoid having to either remove a tranny or mess with the top of it.

edit: And yes I have tried starting in reverse or in nuetral. I also checked for reverse lights which they do come up. One thing to note is when I turn the key into the start position the headlights shut off and when I let go back to run they come back on. I am not sure if this is normal operation to save voltage or possibly a short.

How did you test your battery? Put a voltmeter on the battery when trying to start. Anything below 10v, bad battery.

I didn't test the battery it is fairly new probably one year old.

I need to test the NSS switch or bypass the switch I am just having a hard time figuring out which wire it is. I think it is the white wire from the NSS connector but there are a few others that I will give a shot. I left a link below of the electrical diagram if anyone has a better idea of testing the NSS switch.

https://drive.google.com/file/d/1Grfwu-GG5hSXivJDIBPKbnmMlkZb0Xm_/view?usp=sharing

When my NSS went bad. I would get random door lock/unlocking. No start. But the lights did not dim. Save some time and get your battery tested first. Just because a year old means nothing.

Just because you replaced it a year ago, doesn't mean its a year old. Replaced a battery on a forklift a few years back. Less than 6 months later it was going bad. Took it in and got it replaced under warranty.

A few days later my cousin, whom works at the auto parts store, texted me and said the reason it crapped out so fast was it was like 5 years old. It had apparently sat on the shelf forever and no one noticed. I was just the lucky one to get it.

I agree with you guys that you can have a bad battery even though it is fairly new but none of that matters because I can get the car to crank and start at any time just by bypassing the crank relay using a jumper wire. If the battery was bad I would not be able to start the car by bypassing the crank relay whenever I wanted you know what I mean?

As far as the lights dimming I do not get that either they just shut off when I crank the car like an off switch but there is no dimming. I do get funky sounding noises and flashes sometimes on the dash board though and when I shut the car completely off today I noticed both fans were continuously on even though the car wasn't even started I just checked to see if it would start with the key is all and it didn't but I found it odd the fans kept running. Either I have a battery leak or a short some where or a bad PCM maybe. I am going to take my time on this one because of all the other stuff I have going on and it's also the holidays.

Now that you added more details. I would be looking at the socket connections.

Ignition switch failures were common for GM vehicles back then. Caused some odd electrical problems, just a thought.

After some more examination I have noticed that the starter solenoid wire which goes to the S terminal is a constant 12 volts. I believe this wire is supposed to get voltage only once the key is turned to start position. The battery to starter heavy gauge wire also has 12 volts but it is the smaller wire that attaches to the middle of the starter. It is possible I may have a short which can be the worst problems to solve so I may bypass the crank relay with a fusible link wire with a start button into the dash. I have seen a few people do the same thing on the interwebs.

A constant 12V on the "S" terminal would usually cause the starter to operate constantly.

Since you reported that the starter can be operated by bypassing the start relay, that does not seem consistent.

Blue you make a good point. I will check again and make sure I did it right.

I was looking at the wrong diagram for the NSS switch. I was looking at the transmission range switch or sensor. There is a separate circuit for the NSS switch and when the tranny is in park or neutral the circuit is hot. So I tested the circuit had my daughter go threw all gears and the circuit was hot all the time. So in theory the car should start up in every gear.

Also the ignition wire (yellow wire) going to the PCM lights up when key is turned to start position but the wire from the PCM to the crank relay which is Yellow/Blk wire does not light up. This is the wire I bypassed. This wire must be shorted some how or is maybe damaged some where. I suspect some where in the fuse block under the hood because the crank relay circuit was beeping when I would touch a few of the relays that were close to it and I don't think relays share circuits in the fuse block though I could be wrong.