Pontiac Bonneville A/C And Heater Problems

2001 Pontiac Bonneville.
Question = my a/c quit working ,did not lose charge ,clutch is not engaging,fan blows ok ,controls slow speed and fast work ok ,checked a/c fuse ok,relay ok

Answer:
A few things. Must be sure there is good freon charge. Are you familiar with the use of a test light or volt meter along with a schematic. I can get you a schematic with some help of what circuits to test. The a/c control head sends a request for clutch operation to the powertrain control module(PCM). The PCM looks at a few things to determine if the clutch should be engaged. The PCM grounds the a/c clutch relay, and voltage is sent to the a/c clutch on the DARK GREEN wire, and the BLACK wire on the clutch is the ground side.

VISITOR:
Yes i have a test light and meter. A schematic would be great, thanks.

OK. I will e-mail that info out to you. Let me know if you need more help.

pontiac bonneville

 

 

1996 Bonneville.
Engine size 6 cylinder. Question = Speed control will not work in 90 or above degrees hot weather except when going 70 or above MPH. I have been speeding up to 70 MPH and then pushing the slow button to desired speed. Any suggestions? Bill

Answer:
Check all vacuum lines and connections coming from cruise control module to intake manifold. Possible bad diaphragm in cruise unit, can check with vacuum pump, hotter weather would make vacuum leaks more noticeable. Heat could also make an electrical issue more prevalent although speed should not. The only exception would be a vehicle speed sensor that is not reading correctly. Wiring should be checked from the speed sensor on the transmission to the cruise control switch and to the cruise control module under the hood. The best time to check for problems is when the cruise control is acting up on a hot day.


Pontiac Bonneville SSE. 3.8 supercharged.
Question: heater fan does not work all the time ,i have to open hood and hit it with heavy wrench to make it work, please help.

Answer:
The motor on the fan is obviously getting stuck, and probably won't function at all pretty soon if you have to hit it every time you want it to turn on. You need to replace the blower motor with a new one to fix your problem. You might want to check the wiring as well, if the motor was getting hot, it could have burnt up the wiring which will just cause other problems as well.


Help Keep Us Free-
Tip / Donation To the Mechanics


Q and A Main


How Things Work


Electrical