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

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.

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.
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.

More Car Repair Help