Hello,

I'm having some issues with a few components not working on my 2004 Crossfire, horn, interior light, rear hatch light, BAS, ABS, and rear spoiler random operation that I'm aware of.

I bought the car with minor front end damage 8 years ago; it's been sitting that long as well. Periodically I would start the car and everything worked as expected, however over the past year or so the items mentioned above were not working.

I'm in the process of repairing the collision damage which had nothing to do with the electrical problems I'm having now, I've checked all of the fuses on the central relay module and under hood fuse box and they're all good.

So, my question is ... could it be the BCM causing the issues, and if so, is a replacement BCM a "plug and play" swap or does it need some sort of programming or initialization?

Any thoughts or advice would be MUCH appreciated.

Many Thanks,
Brian

 

How old is the battery and has it been Load Tested ... a full charge does not always mean the battery is good ... even new batteries can be faulty ... random spoiler operation is a sign of battery problem ... take it to AutoZone and they can load test it for you ... whatever you do DO NOT jump the battery

 

DeKalb,

Yes, the battery is good and has a full charge. So what else could it be?

Thanks for the quick reply
Brian

 

THat is not the BCM. You are describing a weak battery OR a water damaged CLP/SSM. Tear the trim out of the trunk and inspect the CLP/SSM for water damage/corrosion.
It is VERY common issue, water leaks in around the rear window and/or fuel filler door, then seeps into the wiring harness, and down into the connectors on the CLP/SSM.

I've fixed four cars now with similar issues (oh, and when the car is a Roadster, the top won't work either), in the last ten years.

 

Pizzaguy,

I replaced the CLP and damaged wire/connectors recently due to water in the area where the CLP is located. It fixed the door locks problem but all of the other issues mentioned in my original post still exist.

So what am I missing?

Many Thanks!!
Brian

 

this does not mean the battery is good ... you need to have it load tested

 

Thanks everyone for your quick reply's ... I'll follow up when I find the culprit.

Thanks Again
Brian

 

Let's take another look:
horn, - bad horn relay (it's on the RCM), fuse 6 on the RCM, bad clock spring, bad horn button

interior light, rear hatch light, - It's an 04, so these work together. Check Fuse 9 and 13, if they are good, the latch and door switches are wired to the CLP/SSM and it tells the BCM over the CAN bus to turn the lights on and off. I've not heard of the BCM failing in such a way these lights fail but I suppose it IS possible.

In short, check every fuse in the RCM and in the big fuse box on the driver's side, under the hood.

BAS, ABS, and rear spoiler random operation
POSSIBLY a bad RCM, but probably not - I'll vote for: weak battery or corroded battery posts/clamps or a resistive ground from block/chassis to battery negative post.
It would be RARE, but if the brake controller is not sending data about vehicle speed, or sending bad data, all these symptoms would be the result - but that is RARE in our cars, I suppose you could have a bad wheel speed sensor, it has happened. But again, kinda rare.

Try James' mod in this thread (it will cost you $20 and 1/2 hour of your time:
https://www.crossfireforum.org/forum...le-engine.html
DO NOT DO MY MOD, I no longer endorse it.

 

Pizzaguy,

Thank you for the reply and information!!

-All fuses have been checked in both fuse boxes under the hood and all are good, no blown fuses found.

-The CLP and corroded wiring/connectors were also replaced on the CLP.

-I looked at the SSM wiring and connector. There was minor corrosion on the SSM connector which I cleaned. (Might be the issue if the SSM or connector was water damaged?)

-The chassis ground is worth investigating. As I said the car was sitting for 8 years to date, so it's very likely. Best guess 7ish years when I noticed the problem with the spoiler and most likely the wet CLP. The first repair was replacing the CLP and connectors back in December, only 2 connectors needed to be replaced, and I was VERY careful when splicing the new wires and plug assembly to the new pump. The pump worked and the doors locked/unlocked as expected.

MANY THANKS
Brian

 

My caution is that you should be VERY CAREFUL about "Cleaning" those connectors - because you cant. You see, the contact between male/female pins is not all that impossible to clean, but the issue is the crimp that you can't clean, that is the crimp between pin and wire. This is where so many problems are caused.

I'ts the contact from aluminum pin to copper/copper clad wire, the arrow points to the problem area:


I first ran into this in the 1980s when working on Motorola Micor/Mitrek radios in emergency vehicles. Some facilities would wash the inside of the vehicle with a hose, they'd cover the radio heads, but then get the cables wet and water would "wick" down the cables and into the connectors. (My first 29 years in the industry was as a field technician doing component-level repairs.)

 

Pizzaguy,

Makes perfect sense!

I'm going to look more closely at the SSM and connector, especially if this module controls interior lights and horn functions.

I sure do appreciate the simplicity of my 67 Camaro.

Many Thanks for all of your help and advice!!
Brian

 

It takes some time to understand how stuff works. Example: The door switches are wired to the CLP/SSM so it knows when to set off the alarm if a door is opened while armed.
But that information is also used to turn the interior lights on and off - so the CLP/SSM has to tell the BCM when to turn the interior lights on.

Many think the door switches are wired to the BCM, but they aren't.



The insanity comes in when you look at the liftgate switch (trunk lid switch), they wired it to BOTH modules. I cant figure THAT out, what where they thinking?

 

Thanks for the schematic and your description!

We "I" have to resist the temptation to over complicate a problem ... 99% of the time the solution is simple but not always obvious.


Again, many thanks for your follow thru on this, it makes a lot of sense!!
Brian

 

Hi Brian,
one other thing to consider since your car has been sitting (depending where you store it) - rodent damage - look for scat and/or damaged wires - they rarely chew through all of the wires in a bundle, but just one or two.
Good luck,
-Jerry

 

I agree, a possibility.

 

UPDATE ... PROBLEM SOLVED.

So I have it all sorted out ... the inoperative horn was an open relay coil for the horn in the Relay Control Module. After replacing the defective repay today the horn is now working as it should.

HORN relay location.


All of the other problems initially mentioned were not related and are functioning as they should. The interior light issue was not related to any other issue and the lights are now working once I placed the interior light switch in the position to activate the lights when the door is opened.

Thanks Again for everyone's help and suggestions ... it was Very Much Appreciated.
Brian

 

Thank you for the update.
I'm glad that you were able to resolve the issue!