Electrical Hell

2000 GTP. The Dual climate control is flickering on and off (in-time with the headlights) and the DIC isn't lit. And no reverse lights.

We traced the flickering back to the EBCM...you can hear (and feel) a relay going crazy in there.

So are 1st step is to replace the EBCM. Think that will fix it? Also, what about the reverse lights and the DIC. The DIC is not lighting up at all and all the fuses are good.

Help! :confused:

CarFlipper

Does the fuse have power? The BCM shares power with other things, IIRC, such as driver/pass door modules, etc. Are all these working fine? It could also be a bad ground causing the relay "chatter".

Does the fuse have power? The BCM shares power with other things, IIRC, such as driver/pass door modules, etc. Are all these working fine? It could also be a bad ground causing the relay "chatter".

Good question, I will check. Thanks.

There's a good chance it's the ignition switch/harness. It's a pretty common issue on GP's and the electrical gremlins you mention are symptoms that it is bad. The AC-Delco part number is D1491D (GM #26068757). Dealer retail is $125.07.

Basically, I agree with Rich that it is probably the ignition switch and harness due to your symptoms. The lack of the DIC and the lighting problems.

I would ensure the battery is good and the charging system is OK. Check the voltage across battery positive and negative cables with engine off and while it is running.

I doubt the BCM is causing the problem. You can check IGN1 and IGN2 circuits for 12 volts to see if the ignition switch is defective if you have a wiring diagram and multimeter.

If by chance the BCM is the cause it will need to be programmed and setup at a GM dealer with a Tech II machine if it is new and not an old pull off a similar year and model Grand Prix. <--- Even a salvaged BCM should be programmed for your car.

Wow, thanks guys! Glad you responded so quickly, the dealer won't take elec parts back so I am glad I didn't install the BCM!

I will order the switch and harness. That actually makes sense. They key got stuck in it a few days ago...I assume that this is another issue linked to the harness?

Carflipper

Before you do, as bnaylor suggested, check the battery cables and connections for corrosion, looseness, etc... IT sounds like the problem, but I'd hate for you to install that harness and find it was a dirty/loose connection.

Okay, we are making progress, so don't give up on me guys! :icon16:

We replaced the ignition/harness and we now have the cilmate control and the DIC lighting up consistent.

However, the key still gets stuck and the blower won't come on for the climate control. :banghead: Also, still no reverse lights and my power trunk isn't working either.

Thoughts????

CarFlipper

Another update: there is power to the blower motor but it willl not work. So we are ordering a blower motor. I hope this will fix it. We also found water in the box????? :shakehead

Also still need to fix the reverse lights, sticking key, and elec. trunk latch. :banghead:

CarFlipper

The last three could all be related to a faulty or out of adjustment neutral safety/transmission indicator switch. For safety, the trunk release will not work and the key cannot be removed when the car is in gear. Also, this switch is what turns on the back-up lights.

Sounds like a combination of problems.

But I had a chance to review the GM GP wiring diagrams. Here what is common to all of your remaining problems.

The B/U 10A fuse (back up) located in the engine compartment fuse box. Check to make sure it is not blown and if it looks good measure for 12 volts at the B/U fuse socket.

This bad boy feeds the backup lamps via the range switch, transmission range switch, park input to the BCM module for the shift interlock circuits, and trunk release solenoid/circuits.

Let us know what you find. Good luck.

Sounds like a combination of problems.

But I had a chance to review the GM GP wiring diagrams. Here what is common to all of your remaining problems.

The B/U 10A fuse (back up) located in the engine compartment fuse box. Check to make sure it is not blown and if it looks good measure for 12 volts at the B/U fuse socket.

This bad boy feeds the backup lamps via the range switch, transmission range switch, park input to the BCM module for the shift interlock circuits, and trunk release solenoid/circuits.

Let us know what you find. Good luck.

Checked the fuse it is good and has power. There is a selenoid at the key we are replacing and we may be running a new wire back to the reverse lights. :disappoin

CarFlipper

Checked the fuse it is good and has power. There is a selenoid at the key we are replacing and we may be running a new wire back to the reverse lights. :disappoin

CarFlipper

Are you using GM wiring diagrams?

Some GPs had problems with the main engine compartment fuse box wiring or wiring getting damaged after severe electrical problems. I recall working on another backup light issue and this guy had wiring problems at the box and associated wiring. I see a pass through in the box in the wiring diagram.

Are you using GM wiring diagrams?

Some GPs had problems with the main engine compartment fuse box wiring or wiring getting damaged after severe electrical problems. I recall working on another backup light issue and this guy had wiring problems at the box and associated wiring. I see a pass through in the box in the wiring diagram.

Found a short in the backup lights...they now work. Down to 1 issue, the sticking key and will have to wait until Tues to get the selenoid from the dealer. :redface:

CarFlipper