VT not starting - immobiliser / BCM??

[Melissa]

Hi Everyone

I'm having trouble with what I believe is the BCM. My problem is identical to this - http://forums.justcommodores.com.au...p-immobiliser-issue-dead-key-please-help.html, although I have been able to start the car after leaving the reds on for at least 2 hours, and I had the car towed home. I even bought the new key yesterday for $90! :supersad:

If I was to get a replacement BCM with the same number/level from the wreckers, along with the matching remote key head, is it just a simple swap? Does it need any kind of programming by an auto electrician - if so, can I still start the car to take it to the electrician after 2 hours on reds after replacing the BCM?? Some threads have mentioned also replacing the ECU also?

Any info would be appreciated! Thanks

Edit - It's an auto 98 VT Exec sedan, if it matters...

 

[accentstencil]

You will need to get the BCM and ECU linked before it will start and I don't think leaving it on reds for 2 hours will work. Linking needs to be done with the right equipment.

 

[Melissa]

Thanks accentstencil!

 

[lout]

did you get the new key remote coded from the old key, from the car or from security card (if from the old key you may have copied a faulty version)
also who did you get key remote from if from a mister minit type there will be specific instructions for first use
Does the remote lock and unlock the car correctly
possibly the wire has come off the back of the keyreader (silver metal trim around key barrel)
need more info
was the remote working correctly prior to this fault ie do you have one fault or two

 

[Melissa]

Hi Lout

I was under the impression that both original key heads were completely flat, so I took the security card with me. He was able to read both original keys and confirmed that the numbers from the keys matched the card security number.

I bought the new key from my local Locksmith, and I did receive instructions -

1. Unlock car manually
2. Get in car, close door and insert key with new remote into ignition. Turn car on and allow to run for 10 seconds.
3. Turn car off. Get out and lock car with new remote.

I tried to follow the instructions, but couldn't, as the car turned straight off. I tied again a bit later, but instead left the reds on for 2 hours, then started & allowed it to run for 5 minutes.

No, I can't lock or unlock the car remotely with the new or old key heads, and the original remote was working perfectly until this happened!

I'll check the wires around the reader shortly and let you know!

 

[nathanVY]

my VT did something similar to this the other day... ended up buying a new key which did nothing

took the battery +ve off for a second, put it back on and haven't had a problem since... sometimes the receivers and get dodgy.

 

[Melissa]

I've tried that too, Nathan. Disconnected it for 10 minutes - nothing. Disconnected it overnight - still nothing. I've also checked all fuses. They are fine.

 

[PRAVX II S]

Did you check for codes? See what code your are getting first then go from there.
Bridge pin 5&6 on the diagnostic connector.

 

[Melissa]

Just got codes 12 & 92 (low speed fan fault)

 

[Brett_jjj]

BCM error codes are completely different to the ECU codes, If theres a problem with the BCM, then it will log its own trouble codes , but these can only be read and cleared via a suitable scantool, (Tech2). You are probably better off waiting for the 2 hours with the ignition key in the ON position to bypass the immobiliser which allows the car to start, and then drive it straight to a holden dealer to see if they can work out whats actually happening with it. If you replace the BCM, you need the ignition keyfob from the exact same car that the BCM comes from, as BCM and ignition keyfobs are security code matched. Also make sure the BCM is the same level as the one being replaced, as there are a few different BCM levels used in these cars, and they are not interchangeable. Theres low, med, high or lux level BCM's available depending on the model, the options fitted, and and equipment level. Also as mentioned above, If either the ECU and/or BCM have to be replaced, then you will need to got them security linked with a scantool before the car will start and run.