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Hi boys,

So i have a customer who has a VS that for some reason doesn't like to start with key (but has central locking function most of the time)

Background is vehicle will not start unless the unlock button is pressed on FOB, which obviously "ok's" the security system through RF
But when the Unlock button doesn't work the car wont start. Which has left him stranded a few times.

I have pulled of shroud to inspect exciter ring and wiring, all looks ok and tight.

I have burnt a VATS deleted memcal but for some reason wont allow the vehicle to start unless again the unlock button is pressed.
Now VT-VY if VATS is removed you can start it with a non transponder key

But VS wont?

Is the way the security handles ignition and starter etc different on the VS compared to VT up?

This is the 3rd VS to not respond to a VATS delete memcal.

You can get them to start by bridging the starter relay with a VATS deleted memcal but cant seem to initiate start on key??


You VR VS gurus please help!

Thanks boys

Ahh get a new key fob?

Clean the slip ring around the ignition and the steel bit on the key with a bit of steelo pad. Also make sure the slip rings are not pushed in so they make good contact with the key head.

assuming the key is in good nick, the issue will be on the circuit between the key reader and BCM, the bcm needs to put out earth to the starter relay for the car to start. If you earth the wire from the BCM the car will crank straight away.

If you find after doing that, that the car will crank but not fire straight away then there is certainly issue between the key and BCM that should be fixed. The BCM sends the 'ok to go' signal to the ECU to allow the injectors to fire.

I own a VS ute that has new key heads, key reader in good nick and all connections are fine. I assume the issue is the BCM itself (often a big delay between turning of key and cranking) i will replace or fix the BCM in this case but you could also just earth the relay wire and the issue would be solved.

Biggvl wrote:assuming the key is in good nick, the issue will be on the circuit between the key reader and BCM, the bcm needs to put out earth to the starter relay for the car to start. If you earth the wire from the BCM the car will crank straight away.

If you find after doing that, that the car will crank but not fire straight away then there is certainly issue between the key and BCM that should be fixed. The BCM sends the 'ok to go' signal to the ECU to allow the injectors to fire.

I own a VS ute that has new key heads, key reader in good nick and all connections are fine. I assume the issue is the BCM itself (often a big delay between turning of key and cranking) i will replace or fix the BCM in this case but you could also just earth the relay wire and the issue would be solved.

Right so if i get this right, the Vats delete will only affect the PCM portion ie Fuel injection, correct key key enables FI, incorrect disables FI.
Vats deleted memcal doesnt look at the key therefore will still enable injectors

BUT BCM also looks for the correct key, so if the correct key isnt present or unprogrammed it will not earth the starter relay at the BCM side therefore not allowing the starter to turn over?
am i on the right track there?

correct

The1 wrote:correct

This has finally answered all my qeustions I've had with the Vr and vs as the vats seem
Never to work right.

Vt to vy seem to be fine with vats removals.

Thanks guys.

Now to trawl through the wiring diagrams to find out which pin is the earth on bcm side.
Or can I earth at relay?

hsv08 wrote:BUT BCM also looks for the correct key, so if the correct key isnt present or unprogrammed it will not earth the starter relay at the BCM side therefore not allowing the starter to turn over?
am i on the right track there?

bypass the starter relay in the engine bay will fix the BCM controlling it if that's your only issue.

This has been added to the FAQ.

antus wrote:This has been added to the FAQ.

Excellent

Thanks