I need to know what else the BCM (body control module) controls because this is what the dealer is telling me i need to fix the Sevice Column Lock message. They say that this part is not covered by the recall.

 

I would insist that they 'reset' the BCM by disconnecting the battery for at least 30 seconds. BCM programming can get into a corrupted state just like any other software. Sometimes it just needs a reboot.

 

Sounds like a dealer scam to try to collect more money as part of the recall, like telling some that they need to replace the column lock actuator when the lockplate is to be removed and a relay harness installed to satisfy the BCM.

 

Not to beat a dead horse, but I did have a BCM go bad in my 2000 coupe. It was caused by water damage due to A/C condensation overflow (plugged drain). So it can happen. But when mine went bad, I got just about every DIC error message possible, the security system malfunctioned, "reduced engine power," etc. Even the rear hatch would spontaneouly unlatch!

 

Dealer is completely full of UNLESS

The BCM has either a B0605 or a B1000 code stored that is CURRENT. B0605 indicates a failure of non-volatile memory in the BCM (and since the BCM uses non-volatile memory ... disconnnecting the battery ain't gonna do much) and the B1000 is a failure of the BCM processor.

However, even IF the BCM failed, it would not cause the "Service Column Lock" message ... the BCM would just fail.

Name that dealer ..... PLEASE

 

Jon Hall Chevrolet IN Daytona Beach!

 

Can a bad BCM cause the 'Service Column Lock' message? Also what components does the BCM control?

 

The BCM is the Body Control Module. It controls many functions, including security. When you insert the key, for example, the BCM tests the resistance in the "pellet" of the key to determine if it is correct. When the key pellet matches, the BCM sends a password to the PCM to allow the vehicle to run. The BCM also controls functions such as the column lock. If the BCM determines the column lock is "ON", or locked, and the engine ignition is in the ON position, the BCM commands the PCM to shut down the engine so you cannot drive the car with the column lock ON. It also commands the IPC to display the SERVICE COLUMN LOCK message as it knows that the column lock should be OFF with the ignition in the ON position.

It also either directly, or through coordinating with other modules, controls functions such as the seats, mirrors, lights, locks, windows, etc. The list is too long to go into in detail.

I cannot imagine that a bad BCM would cause a COLUMN LOCK message without there being something wrong with the lock.

The BCM is a computer. It has a set of internal diagnostics that it runs when the ignition is turned on. If it fails the tests, as I said before, it sets either a B0605 or a B1000. Other than those two failures, I have not seen any conditions in the Service Manual that call for the BCM to be replaced.

Demand that the dealer show you on the DIC the codes that are set in the car, and look for either of these two. If they are present and CURRENT (such as a B0605 C code) then the dealer may be correct that it needs replacing, but given all the problems with the column lock itself, and the fact that it is almost impossible for the BCM to fail without many other symptoms occurring, I doubt you have a bad BCM.

Are you sure the dealer is saying it is the BCM that is bad? There is an "Electronic Column Lock Module" that is mounted on the steering column. The last time my car had the Service Column Lock problem the dealer told me this is what failed and it is not covered under the recall.

I did what is always best, I calmly stated that I didn't care what part failed, the column lock is a known issue with the Corvette and GM needed to make it right. I pointed out that the car had left me stuck in a parking lot, on a weekend, and I'd had to get it towed in for service because of the column lock, and that I'd brought it in before to have this problem addressed. I asked the dealer to get back to GM and point out these issues and let GM decide what they would do.

A few minutes later the dealer called me back and assured me GM had agreed to replace the part as part of the recall. Now, do I know if this was really what was happening, or just the dealer looking for a way to make some money ?? I don't know or care, all I wanted (and I made this VERY clear to the dealer up front) was for the column lock problem to be fixed on GM's dime, not mine. Put the onus on GM, and a decent dealer will get this fixed at GM's expense, not yours or the dealer's.

HTH

 

For the Information. That is what i was looking for. I needed some knowledge before i could challenge the dealer.