VX COMM, possible immobiliser issues? pcm can't be found with tech 2

[sv9946]

Hi guys,

Having some issues with a mates january 2001 built VX series one exec sedan. Early last year it had some BCM issues, so the BCM was replaced and a new key head made, since then its been running like a charm, with the only problem being it has had the message "serv ERROR" come up on the instrument cluster, but has been doing this for years and hasn't affected it - i dont know what this message means?

however early this year the car just wouldn't start! when the key is turned over, it wont crank at all. if the starter motor relay is bridged, then it cranks but won't start. seems like an immobiliser issue to me?

plugged the tech2 into it, tryed to connect to engine module with the following response - No communication with vehicle. i have since tryed the PCM in a mates vx, and it is fine. so the PCM is known to be good also now. done a DTC check on the bcm - one code only which was 0007 PCM Data lost (when erased, came straight back) so at that stage, i tryed to do a BCM link to PCM/PIM thinking maybe it had lost its connection with the response from the tech 2 "function rejected by PCM" however as mentioned earlier the pcm would link no problems at all in another vx.

only other DTC's in the car were in the instrument section - maybe why "serv ERROR is displayed? and they were
11 - current No serial data from PCM &
17 - current BCM fault logged in BCM clear DTC from BCM

when i attempt to start it, the immobiliser LED doesn't flash, nothing goes wrong, just it won't start. i've tested just about everything and i'm certain its an electrical issue, but i can't pinpoint it. i'm asking if maybe any holden employee's that understand these codes have any ideas or even thoughts on what to check?

thanks guys

Matt

[wamboin23]

sounds to me like the BCM and the PCM have lost comms on the serial bus.

possibly a broken wire, or faulty BCM.

get a wiring diagram, check for continuity between PCM and BCM on all wiring you can see that goes between them. if this is ok, i'd be trying another BCM.

[lout]

blown fuse under dash to pcm

[ka1sa226]

Having the same issue here, did you end up solving it?