Srs dash light, staying on after battery disconnection

[redvxr8clubby]

That is odd, even my VT2 needed a PIN for the stock head unit.

VT VX need pin, VY you don't have to enter the pin after battery out, from previous threads I believe the BCM effectively re enters the pin, so as long as radio unit is still in the same car (same bcm) no pin has to be entered.

[DEVLGM]

I find it humorous that they had a pin in the first place.
What thief would look inside a car and go "beauty, a stock commodore stereo, I'm going to nick that".

[IJ.]

So how do I know if that's the defiant prob?? And is it as simple as, new one, plug in, all good??

If you get a new one it all has to be relinked with Tech2.

[amadvk]

Is that a big job? Or straight forward??

[VTClubSprtR8]

Had a problem like this in one of my cars turned out to be a dead PIM.

If the car will start and run it won't be the PIM (Powertrain Interface Module), hence the Tech2 had comms with the PCM (Powertrain Control Module) Sounds like the secondary and tertiary serial data bus switching in the BCM has eaten a bag of. Does she still start and run?

To replace the BCM is pretty easy to do it just needs to be linked to the other modules. The bad news is if the BCM is replaced it will also need two new key remotes programmed with it.

[amadvk]

Cheers clubsprtR8!!! Yeah mate she runs fine, no probs there, it's just got the few probs that I indicated in the thread, where is the bcm located??

[VTClubSprtR8]

.....where is the bcm located??

Right up under the dash near the steering column to the right, will be a Tech 2 or Scantool job to program once it's all swapped out to link everything up.

Are they sure it's the BCM that is shot?

[amadvk]

Ok so it's In at Holden at the moment, I bought a second hand bcm and matching key fob, the tech 2 still can't communicate with the other bcm???? What else could this be????

[Cobalt]

This is one of two things.... A faulty module or a wiring issue...sung as a bad ground.

Check the ground points that are close to the battery...these may have bee interfered with when that battery was disconnected for charging. The main ground is just in front of the cruise control module mount.

If these are good the you need to unplug each of the items on the bus till you can communicate. Start with the radio....

The cluster will report a srs fault if it can't see the airbag controller due a bus comms problem

Items on the bus are abs, srs, cluster, air con pressure switch, radio, pim, climate control and bcm...key slip ring. Think that's all....

The bcm may not be faulty just that the tech2 can't communicate with the bus grounded by a faulty device.

The easy ones to get to is the pim... Tis is commonly faulty and I have had them give strange problems after disconnecting the battery...

Seems stange that the car runs fine ... Usually the vats must be disabled for the car to run with a faulty pim....

That should get you started...

Cheers

Chad

[IJ.]

Chad, is the light sensor/antenna on that bus as well?

[Cobalt]

Pretty sure that is direct bcm connect....bcm puts that info on the bus for climate... But would have to double check the wiring diagrams.....

Antenna is bcm connected