1995 Buick Cruise Control

I have the same problem that Ron had with his Cruise Control

Automan #53. I would like to know what Ron did to solve his problem.
Hope you can answer this for me.

Avatar 307 had similar problem, and said that he changed sensors on the front of engine that controlled the fans. However my AC works OK

Cruise will stay on for only a few seconds.Need to shut off engine re engage. Occasionaly it will work, for a short period then quit. 99% of the time it does not work.

Would appreciate hearing from Ron or someone.

Waynen

Clean the vaccuum servo brake solonoid needle valve.. EASY... It takes 20 minutes.

My cruise works at first and then shuts down. At first it was only occasionally, but now it does it almost every trip. I had a GM dealer check it out and after three trips to the shop and five hours in the waiting room, all that the could come up with was a bad ground (which they supposedly fixed). I have replaced the vacum servo, and just today replace the Electronic Control Module (computer) and it is still a problem. Do I keep replacing parts or is there an answer to this problem? Please Help!

I had a mechanic clean my servo, but it did not do any good. Put a new one on, and it still does the same thing as your. Wish there was some way one could contact General Motors and get an answer.

It seems like every mechanic just does trail and error.

Guess I will have to live with it, or trade the car off.

Finally got my cruise to work. Replaced servo with a rebuilt one. Still didn't work, so went back. Code said it was the servo. So put another new rebuilt one on. Still didn't work, but now the code said to change the brake switch. Put a new switch on, for $10.00 and it works perfect now.

The shop I went too has a computer and was able to put up the memos put out by Buick. It explains it in detail, along with drawings showing the problem.

The cost to the mechanic for the switch was $5.00. I gave him $10 for profit and to put it on.

The first go around cost me $168. This whole thing is mostly trial and error, so try and find a small garage mechanic that won't hold you up.

Wayne N.

Meant to mention the Code numbers were 562 and 561. 562 was vacum which was OK and 561 was Vent.

Part number for the switch is 2555 1819

Wayne N

I have been chasing a very similar ongoing issue with the intermittent cruise control in 95 Park Avenue. The cruse would occasionally work fine for shorts periods but generally will only come on for 3-5 seconds and go off and not come on again until after car has been shut-off and restarted. We have checked and double checked everything, and we still get a DTC code 1561 and 1562 and the cruise light drops off after a few seconds and will not re-set until the car has been shutdown and restarted.

Reviewed TSB 63-90-02 and the service manual on cruise control: Section 6E3-C17, chart C-17 and Chart C-17 (attachment 2) for the 1995 Park Avenue.

Here is what has been done:
1. Removed, checked reinstalled the brake switch's, both the TCC/Antilock and the cruise/shift interlock and all the electrical contact pairs read 0 Ohms resistance. (note the vacuum valve on the TCC antilock switch holds (seals) perfectly, releases when brakes depressed.) [We had previously changed the cruse/shift interlock brake switch a few years back which did not correct the issue but we have rechecked the old switch and validated the old switch was in fact bad (6 Ohms resistance)]
2. Next we replaced the connector on the Vehicle speed sensor (VSS) on the transmission. Note the sensor was changed a while back for another issue but it did not fix the cruise control and the speedometer has always worked great, we changed it because the old connector looked to be bent over and thought might have a poor connection.
3. We removed and checked the Cruise Control (vacuum) servo, even disassemble and cleaned and checked the internal vacuum vent solenoid. We also checked the one in the car against the spare one we replaced a few years back and both are exactly the same readings across all terminals, with no open or shorts.
4. We checked the vacuum and hoses, we found the cruise servo still holds and has good vacuum when you pull a hose even after the car has been shut down for some time. We did find a very deteriorated hose between the manifold and the firewall where it splits going to the A/C and the cruise servo, but changed it and problem still the same after replacing.
5. We carefully checked all five wires (ohm checked and wiggled around) for shorts to ground, shorts between each other or open between the computer connector below the glove box and the Cruise Servo. All the wires read 0 resistance and steady solid with no intermittent jumps.
6. We ops checked numerous times after checking different things and still have the same issue with the cruise dropping off, and once the light goes out it will not reset or restart the system until the car as been shut-off and restarted. We did note that is seems to work some of the time when cold a little better, but there are times it still fails cold.
7. We do get a 1561 and 1562 DTC code most every time, indicating a short or open between the computer and the servo, but everything has double checked good. We shot every wire, several times.
8. Tried another PCM, still no go. Still had the exact same problem. However I did find the computer case had a high resistance to ground. (Like 0.534).
9. I disassembled the ground connectors by the battery to the fender and the two grounds (one on each side behind the carpet on the left and right side kick panels under the dash, inside the front doors. I also changed the brake switch while I was there under the dash on the driver side cleaning the grounds and between these two things it fixed/reduced the PCM case resistance to ground to 0.00 and fixed the issue. the cruise control has been working great. Took a while to find this problem and hope this helps someone else correct their problem quickly!

Thanks and have a great day!

A lot of cruise problems was the brake switch on LeSabres and PA's....sometimes it was just an adjustment......

In the 2000 models where the on/off switch was in the steering wheel, the problem was the on/off switch.....easy to diagnose......take car for ride press switch on, hit set and if it didn't work, hold down the on/off button and set cruise...it would work....soon as you let go of on/off switch, cruise would stop working.....easy to replace using a right angles pick, just get behind switch and pull out....some times there wasn't much slack in the wiring and it could be a tight fit....