Electrical Gremlins... HELP!?!

thebeef74 · 29th April 2010, 04:24

As much as I hated to click the "New Thread" button, after about an hour of searching for a similar problem, but came up with nothing.

None of these problems affect the driveability of the car. They are just inconveniences and keep my car from being otherwise perfect.

The major:
My A/C compressor will not turn on. Fans, heater, vents all work and are fine, but the compressor will not kick on. I live in a place where A/C is not an option.

If I leave my key in the on position when I pump gas and try to start, the car will sound like it is firing and then immediately shut off. Unless you lock, unlock, open door, close door, and reset the key, in this order, you won't be going anywhere.

The minor:
Occasionally, the "code" feature will require me enter "0000" before it lets me start.
There is a massive delay in the high beam indicator light (like 10 to 15 seconds) after they have been turned on/off.
Fog light indicator comes on or off on its choosing.
Board computer forgets things, a lot. Forgets date/time, forgets gas mileage, sometimes wont come on at all.
Heated seats will only work now and then. More often than not it will blow the 25 amp fuse (i believe its number 31) that controls the heated seats and the rear sunshade.

I think that's all but I'll post more as I notice them. I also am starting to believe that this is all because of the DME. I have checked quite a few wires all fuses and all relays that I could see. Any input on this would be fantastic.
Thanks in advance
-Beef

chowdah · 29th April 2010, 04:30

Battery age and condition?

thebeef74 · 29th April 2010, 04:37

I bought the car in Aug/08 w/50k miles. Never changed the battery, but it looks like its in great condition and it holds a charge well.

blackxs · 29th April 2010, 04:43

Quote:

Originally Posted by thebeef74

The major:
My A/C compressor will not turn on. Fans, heater, vents all work and are fine, but the compressor will not kick on. I live in a place where A/C is not an option.

If I leave my key in the on position when I pump gas and try to start, the car will sound like it is firing and then immediately shut off. Unless you lock, unlock, open door, close door, and reset the key, in this order, you won't be going anywhere.

A/C problem could be the A/C compressor, make sure it is in operating condition with the right amount of refrigerant. This could also be a problem with the interior air temp sensor, if you are using the "Auto" function and not just blasting the A/C.

Second problem could be an issue with the ignition

Quote:

Originally Posted by thebeef74

The minor:
Occasionally, the "code" feature will require me enter "0000" before it lets me start.
There is a massive delay in the high beam indicator light (like 10 to 15 seconds) after they have been turned on/off.
Fog light indicator comes on or off on its choosing.
Board computer forgets things, a lot. Forgets date/time, forgets gas mileage, sometimes wont come on at all.
Heated seats will only work now and then. More often than not it will blow the 25 amp fuse (i believe its number 31) that controls the heated seats and the rear sunshade.

I think that's all but I'll post more as I notice them. I also am starting to believe that this is all because of the DME. I have checked quite a few wires all fuses and all relays that I could see. Any input on this would be fantastic.
Thanks in advance
-Beef

The "code" problem, the board forgetting things, the seat problem all sound like an electrical issue. The code though has never shown up on my car even with the battery off for a long time, so you may be right in thinking its a DME issue. The other issues definitely sound more like an LCM specific issue because of the fog light indicator and high beam delay are both specific to it

TexaZ3 · 29th April 2010, 05:13

Do you have access to Peake scanner or the like? Get the codes read, it should give you some ideas, at least where to start.

thebeef74 · 29th April 2010, 05:26

We ran 12 volts directly to the compressor and it did kick on. That's when followed it to the ac control unit eventually found there is no relay for the ac, just a direct wire to the DME.

I also ran the Peake Scanner and go a code for an "e-box fan" which is in the same neighborhood as the DME.

What is an LCM?

blackxs · 29th April 2010, 05:56

LCM is the light control module.

I would replace the DME at that point though

AMP · 29th April 2010, 06:13

Quote:

Originally Posted by thebeef74

I also ran the Peake Scanner and go a code for an "e-box fan" which is in the same neighborhood as the DME.

Don't overlook this one.... you're sooo close...

Sorry, I'm in an odd mood.

The eBox has a cooling fan which, IIRC, draws cool air out of the cabin in order to keep the DME and the other modules from overheating in the engine bay. The odd behaviors that you are observing may simply be the result of the DME running too hot. Look into the fan malfunction before you worry about any of the other potential causes.

thebeef74 · 29th April 2010, 06:14

Quote:

Originally Posted by blackxs

I would replace the DME at that point though

Thats what I was afraid of

thebeef74 · 29th April 2010, 06:58

Quote:

Originally Posted by blackxs

LCM is the light control module.

I would replace the DME at that point though

Quote:

Originally Posted by AMP

Don't overlook this one.... you're sooo close...

Sorry, I'm in an odd mood.

The eBox has a cooling fan which, IIRC, draws cool air out of the cabin in order to keep the DME and the other modules from overheating in the engine bay. The odd behaviors that you are observing may simply be the result of the DME running too hot. Look into the fan malfunction before you worry about any of the other potential causes.

All these quirks started happening before the e-box fan code came up though. Maybe it took too long to show up and already fried things?