0Superman09

Ok, another thing to mention....

I turn my headlights on and inside, my gauge cluster lights up, and the buttons around it also light up (HUD, dimmer, fuel, options, reset, etc) But the lights for the door button controls (windows, memory, locks) do NOT light up!

ajg1915

Have you checked the DIC for codes ???

First rule of electrical work is to unplug the battery, I know it won't help you but to others who play around in the electrical system, make sure you undo the positive wire to battery when working on the car's electrical system.

lucky131969

If you have no communication on the serial bus, you won't have any lighting at those positions. The signal from the dimmer control and IPC is converted to a serial data message to control the lighting for those modules.

Unfortunately, it is not possible to isolate this lighting serial data, because it is connected via S206, so unplugging star connector 2 will not do it. That's why I suggested making a jumper assembly for star connector 1, so the systems could be isolated.

A final caution on the BCM. Since you do not know the nature of the failure for sure, you have a known bad position. I think it risky, to install a known good BCM, into a known bad position. If a condition exists that fried your current BCM, it very well may do the same to the new one you install.

0Superman09

ea, definitely an oops on my car on a few levels, lol. Live and learn... I can tell you I won't do this again now!

I cannot read the DIC for codes.... it just shows up as No Comm....

ajg1915

That sucks, too bad you're so far away as I have a Tech2. How far are you away from Dr Phil ?

I would reach out to him for some help.

0Superman09

half hour or so. I may give him a call tonight! Thanks!

ajg1915

I think that would be your best choice, as Lucky stated you might still have an existing short and up wiping out the new BCM.

Electrical problems suck.

lucky131969

If you have no communication on the serial bus, you won't have any lighting at those positions. The signal from the dimmer control and IPC is converted to a serial data message to control the lighting for those modules.

Unfortunately, it is not possible to isolate this lighting serial data, because it is connected via S206, so unplugging star connector 2 will not do it. That's why I suggested making a jumper assembly for star connector 1, so the systems could be isolated.

A final caution on the BCM. Since you do not know the nature of the failure for sure, you have a known bad position. I think it risky, to install a known good BCM, into a known bad position. If a condition exists that fried your current BCM, it very well may do the same to the new one you install.

0Superman09

It may but I am almost positive my problem is non-existent anymore. As soon as I snipped those 3 wires (together) they shorted and blew my #5 fuse which I also believe took the BCM with it. THose wires are not shorted anymore and therefore should be fine I'm thinking. I will give it a shot and see how it goes. But my problem occurred immediately when I shorted out those wires by snipping them together.

Bill Curlee

I cant see how the BCM could be bad by cutting the Changer wires.

So that being said, go back and do this. Reassemble the STAR connectors and make sure that you still have the issue. If you do, find the star connector that only has F O U R wires and remove that connector shorting bar. That will eliminate the LDCM, RDCM and the Seat Control module as part of the issue. Then see if you still have a NO COMMS issue

Next, if theres another module that causing the serial buss to short, you can remove the other shorting buss bar and use an OHM Meter and read each module serial wire to GROUND.

Ues the schematic that LUCKY provided to see exactly what module your reading. Let us kno what you find.

Bill

If I remember correctly, they read around 750 ohms. If one reads ZERO, that module is your issue. The serial buss isnt a power buss. It just has a signal on it so shorting it out wont cause smoke and flames. Just a NO COMMS issue.

tstar

This is getting more and more interesting... I think the theory the OP is running on is that when he cut the wires, voltage was briefly passed to the serial buss... Which caused the problem.

Plausible, I suppose. I agree that it sounds far fetched to believe that cutting the CD Changer wires fried the BCM...

He had a 20 amp fuse in slot #5... I wonder if the voltage was strong enough to damage the shorting bar????

Tim

0Superman09

When you say reassemble star wires? You mean just yank them out and push back in? I inspected and both connectors look fine, nothing funny.

I unplugged the back of the connector with 4 wires and I still have my issue.

I don't have a meter for reading the output

And for the record, the star connectors are the 2 plugs to the left of the BCM, grey in color, that have wires going into them and a plug on the backside with prongs in it correct?

-Jon

tstar

Correct those are the ones... He means if you pull the shorting bar out, the plug with the prongs on it. That will "unplug" all the modules terminated to that connector from one another. If one of those were bad and shorting out the buss it would clear the BCM issue.

So none of the prongs looks burnt?

Bill Curlee

Jon

If you just un-plug (remove the TOP) from the one with FOUR wires, does the problem resolve. If you disconnect BOTH plug tops, you will have NO COMS forever.

If disconnecting the FOUR wire connector doesn't resolve the issue, you will have to break out a meter or find someone that has one to conduct Resistance checks.

BC

0Superman09

Right on, I tried disconnecting the many wired one, the 4 wired one, and both and every situation all still received No Comm.

Bill Curlee

You have a ground on the serial buss somewhere. Remove both shorting bar tops from the star connectors and read each wire to ground. Doing that will show you which wire / module is causing the issue. Untill you do that, your all stop.

Bill

0Superman09

I apologize for my ignorance but I am terrible with electrical stuff. How do I read this?

Bill Curlee

Try this!! Remove both connector caps and jump pins M & B together. That will restore the comms between the BCM and PCM. Thats all the car need to start and run. See if you can do that.

BC

0Superman09

Cool! now how do I go about jumping this? just add some wire between each?

So I remove both grounding caps and run wire between pins M and B?

0Superman09

And if I'm reading correctly, both M and B are on the same connector? light green and dark green wires?