Mechanics

AUTOMATIC HEADLIGHTS SHUT OFF WHEN

2000 Pontiac Grand Prix

Heater problem
2000 Pontiac Grand Prix 6 cyl Front Wheel Drive Automatic 74,488 miles

My Automatic Headlights turn off when the blower is turned to any speed besides off and the blower intermitently will only blow on the highest fan setting. The headlights work fine when they are switched on manually while turing the heater/blower on. This car has a standard climate control and does not have a dual climate control.
Avatar
Djdomin
January 29, 2010.




Was wondering if you ever found out the problem with your car? I have the same problem the blower and the dat time runing lights turn off at the same time and they will turn back on together it only does this every once in a while

Tiny
Nowitzke
Feb 27, 2010.
Hello,
No unfortunately I have not found a resolution to my problem yet. It's a very strange thing. I have made a recent discovery though. If you turn on the rear defroster and turn it back off or just leave it on, the glitch with the automatic headlights going off when the blower is on goes away. I have been told from a friend that is good with cars it is probably a bad fan switch and may have a short in it. What I found ironic is that the climate control and the headlight system both route through the Body Control Module (Computer). I plan to try a replacement fan switch and see if the problem goes away. I will keep you posted on my findings.

Tiny
Djdomin
Feb 28, 2010.
Thank you I will do the same
AD

Tiny
Nowitzke
Feb 28, 2010.
Hi djdomin and nowitzke,

I had a similar problem with my daughters 2001 Pontiac Grand Prix.

There is a Blower Motor Resistor that is connected with the Blower Motor. This is where the power for the various fan speed positions comes from.

My daughter's car only had power to the blower in the highest position and sometimes it wouldn't work at all.

After the resistor was replaced, the blower worked as advertised in all positions.

I hope this info is of use to you both. Good luck.

TakeChargeSarge

Tiny
TakeChargeSarge
Mar 1, 2010.
Took the car to the shop and they could not find any thing wrong with it. Sombody has to know what is going on. That is what I have found out so far

Tiny
Nowitzke
Mar 6, 2010.
Your problems lies in the ignition switch. But first you need to investigate the resitor located on the passenger side clear up under the dash by the blower motor. You will have to pull the carpet and padding back to see it and to get to it. Total pain in the rump. But still needs investigated to see if the resitor pack is fried or not. If you resitor is in good shape, it is absolutely your ignition switch. Been there done that. When the igniton switch goes bad, it affects the DRL and HVAC, AC, interior lights. Just about everything. And you might not be experiencing all of these, but most of the time if you are having more than just one problem. It's the ignition switch. Good Luck : )

Tiny
Smax23
Apr 5, 2010.

AD