Electrical gremlins!?

**speedyWS6** · 06-07-2015, 09:08 AM

Guys....

Went out for a good drive in her today up to a buds parents house as he is back from
working in S. Korea (Rolls Royce Aero).

Now... we went off with his fancy camera for a few (loads) of pics and i may dabble in
COTM but to the problem.

Martin noticed all of the courtesy lights staying on with the doors and trunk shut and we
simply could not get them to work correctly, that is to say go out with the usual few secs delay
when all shut up. So i plucked the fuse out and figured it's not a huge prob and i'll get to it
but..... The key fob is all screwy too!! If all is shut and i press lock, it gives it the usual double
beep but it does not physically lock the doors??! They still open and if i do open the doors,
the alarm fires right up to annoy all the neighbors.

The battery in the fob seems lively
enough so that is not it i don't think? Also... we could not figure out how the car "knows" the
doors/trunk are shut as there are no little plunger switches anywhere on the door jambs?!

I have disconnected the battery and locked the doors manually for now but i want to figure this
one out as soon as i can

Something else we noticed was a random click from behind the glove box, right where the DRL
module lives but due to the lighting mods i had to get done to comply with our daft rules the DRL
module was bypassed to allow the front DRL's to become turn signals/side lights.

HELP!! I can wield a welding torch but electrics... nope.

Any ideas welcomed!

Trev

**pajeff02** · 06-07-2015, 06:22 PM

Sounds like a possible BCM (Body Control Module) issue. There are soldered joints in the BCM that go bad over time and cause all sorts of weird electrical issues. Essentially, you have to remove the BCM, open it up, and touch up a couple of soldered connections on the circuit board. Not sure if we still have a good set of instructions on here or not. Smittro had the best thread with lots of pics but I think he took it down.

**pajeff02** · 06-07-2015, 06:25 PM

Ok - check out this thread: http://www.ls1.com/forums/f6/body-co...joints-165491/

**speedyWS6** · 06-07-2015, 11:35 PM

Thanks Jeff!

Had a look at Smittros info and it looks fairly straightforward???

Looks like I will be delving under the glove box sometime soon.

Also... Just how DOES the car know the doors are shut for the
courtesy lights as there are no plunger switches I can see.... anywhere?

Trev

**pajeff02** · 06-08-2015, 04:34 PM

I believe it is a switch built into the latch assembly.

**speedyWS6** · 06-08-2015, 11:02 PM

I have just been having a good read on Tech about this issue and one guy near the end of 18 pages
worth of info states... "Sorry, this is not the fix. Yes, chances are good that your lock problems are BCM related.
But the BCM has several distinct circuits and the fix in this thread is for the Retained Accessory Power (RAP) circuit
affecting the windows and stereo. It is not related to the power locks circuit". So... does this mean that the 5 highlighted
solder joins may not be anything to do with the alarm and locks?

I did see a lot of people stating they had radio and power window issues with the BCM but not many mentioning the locks
and alarm?

I suppose the BCM will be my first try at a fix, but I hate electricals with a vengeance!!!

**pajeff02** · 06-09-2015, 02:56 AM

It certainly isn't going to hurt anything to crack open the BCM to inspect the solder joints. Use a magnifying glass and carefully inspect the board for cracks or loose components. You may also have a wiring issue in the door harnesses and the most likely area to check is where the harness runs through the A-pillar and into each door.

**speedyWS6** · 06-09-2015, 10:52 AM

OK,

I am limited for time to be able to fiddle with
this during the week but i got under the dash for half an hour tonight.

Christ.... what a game it is going to be to get this damn thing out!!!?

I peeled back the glovebox lid clips and it swung down out of the way but
gimme a break!!

people talk of tough clips which need a good bit of levering/prying.

Is this a pic of one of the clips,

and if it is..... how in the hell do you lever
at the other side which is completely un get to able!!!?

If these are the clips, do i pry and release the BCM "just" with the release
of these or am i missing something?

Also... is there an easy way to undo the wiring plugs as they all seem to have
those one way barbed type of fastening and i am losing the will to live!

**pajeff02** · 06-09-2015, 11:28 AM

Fortunately, I have never removed our BCM.

If you need better instructions, I can find the appropriate section of the service manual and post up whatever it says to do.

**speedyWS6** · 06-09-2015, 12:37 PM

Jeff,

Please do!!

I would welcome any help with this...

Trev

**pajeff02** · 06-09-2015, 04:10 PM

Ok - here be some info:

BCM is definitely in charge of the interior lights, door locks, hatch release, horn, fuel enable control, seat belts, anti-theft, etc... Interestingly (and I did not know this) the BCM can flash DTC's (Diagnostic Trouble Codes) through the security light. To enable diagnostic mode, perform the following steps:

1. Turn the ignition switch to the RUN position.

2. Turn the ignition switch to the OFF position.

3. Remove the Radio fuse from the I/P fuse block (driver's end of dash, can be accessed only with door open).

4. Turn the ignition switch to the ACCY position.

5. The BCM will sound 1 or 2 audible warning tones.

6. Within 5 seconds, turn the ignition switch to the OFF position and immediately (within 1 second) back to the ACCY position.

7. The BCM will sound 3 audible warning tones.

The BCM will then begin to flash DTC's using the security light within 4 seconds. Each two (2) digit code is flashed three (3) times, with a short pause between digits. DTC's are displayed in numerical order and the list will continue to repeat itself until diagnostic mode is exited. First code should be a "12" which indicates that the BCM is in diagnostic mode. The final code that will flash will be "55", followed by a two (2) digit configuration number, before it then cycles back to 12 and repeats itself. If it only shows codes 12 and then 55, there are no DTC's set.

**pajeff02** · 06-09-2015, 04:16 PM

More info:

BCM DTC's can be cleared by pressing and holding the door unlock switch for 4 seconds while in diagnostic mode. The BCM will sound 3 audible tones to confirm that they are cleared. It will also clear the DTC's automatically once the fault is corrected.

To leave diagnostic mode, turn the ignition switch OFF, reinstall the radio fuse, and then turn the ignition to RUN.

To remove the BCM, disconnect your battery, remove something referred to as the "instrument panel insulator", and simply release the BCM from the HVAC duct by pulling the bottom towards you. Disconnect all three (3) electrical connectors and that should be it.

The actual BCM DTC's are kind of scattered across various sections of the service manual and there are too many to type up.

**speedyWS6** · 06-10-2015, 04:48 AM

I appreciate the effort you have gone to, Jeff!

It is turning into rocket science.......

**speedyWS6** · 06-10-2015, 09:49 AM

"simply release the BCM from the HVAC duct by pulling the bottom towards you.
Disconnect all three (3) electrical connectors and that should be it."

I had to laugh at that line Jeff!!! I have just spent almost two traumatic
hours which i'll never get back!! wrists all torn up with all the sharp pointy bits
but..... I have the bloody thing out.

The right hand clip is a b*st*rd.

I suppose i could add a few thoughts on it's removal but i reckon it has all been
said from what i read on the forums...... I DID find that a small piece of wood
such as a Popsicle stick is useful for just holding the left clip open enough while you go
at the right hand clip. As it is thin it doesn't compromise the sliding out aspect
once you have the right hand one free. Still a PITA though!!

I was hoping to see an obvious dry or cracked joint but the crucial "5 in a T shape"
appear ok but obviously they will get the soldering iron treatment to re-rejuvenate any
loss of quality.

**speedyWS6** · 06-13-2015, 02:43 AM

Well,

I found the time this morning to refit the BCM although by refit i mean
plug in the wires as i have no intention of pushing it back up in place until
this is fixed.

So.... it is well and truly NOT fixed as it is still doing the beep beep with no
locks activating and then sounding the alarm if i open a door. I am really hacked
off at this as i hoped this known re solder trick would sort things out!?

I found the re soldering of the "T" joints really quite easy so i know that bit went well.

Any further ideas welcomed!!

**speedyWS6** · 06-13-2015, 04:52 AM

Well,

Tried the BCM diagnostic thing with the security light.

Bit of a work up but i have a list of codes. Yeah... list!!

They are... 31, 33, 34, 35. The 12, 26 and 55 showed but
they are not a concern...

I also discovered that when the courtesy light fuse is IN and
the courtesy lights incorrectly stay on permanently the key fob and central
locking DOES work as it should but if i remove the courtesy light fuse the
locking and alarm then goes to hell and fails to work properly at all!?

The car starts and runs fine but i am hesitant to use it as i may get stranded
out in it and end up in a world of pain getting recovered!

I found a list of codes here.. Body Control Module Diagnostic Trouble Codes: Computer Problem ...

Reading this list makes it appear as though it is a ground problem common to
the courtesy light, RAP feed and seat belts?

Oh man... what a pain in the *ss this all is.

Help......

**0rion** · 06-13-2015, 07:19 AM

I can't offer up much help really as I've never ran into this issue but the very first place I would start is looking at the light sockets to make sure they're not corroded. It's the same as the turn signals....when a socket gets corroded it can do some crazy shit to the electronics. It's quick, easy, and free so that's where I always try to start.

**speedyWS6** · 06-13-2015, 09:13 AM

I understand what you mean but....

ALL of the interior lights stay on, both the lights
on the rear view mirror and the one at the back over the
rear seats. The mirror lights don't respond to any button pushing,
just on no matter what until the fuse gets pulled and then the
lock/alarm issue gets going.

I cannot see it being all at once! Fully understand your thoughts tough.
I HATE electrics! I have just started making a custom strut brace and
that is where i am in the zone!!!

Trev

**0rion** · 06-13-2015, 09:20 AM

what about the door switch in the latch? Have you tested those at all? Makes a lot of sense that one of those could be bad too. Should just be a simple open/closed switch and easy to check with a meter.