2005 VZ doesnt start, mechanics have no idea what the issue is. (Car started 12 hours prior) please help me

[jonmuay]

Hi guys I'm really hoping someone can help me out here with figuring out why the car won't start.

First I need to explain some backstop as it could be relevant.

6-12 months ago I went to Mr minit man and they made me a new key and central locking thing for my car as my original one was falling apart. After they made it, I took the key home and coded it to the car (doing the thing where you lock it, put key in ignition etc.) It worked. And I've never had any dramas with the car or the key ever.

Fast forward to 4 months ago, I got a new work vehicle and stopped driving the Holden. The Holden has been sitting since then.

Fast forward to this week. I booked the car in with the mechanic, I went and got a new battery for the car as it was dead. I installed the battery, unlocked the car and turned it on. Everything worked fine.
The next day I got home from work, drove the car down to the mechanic and handed them the keys.

I then get a call the next day asking if there is any special method to turning the car on. The mechanics stated that the afternoon I dropped it off they turned it on and drove it into the shop to store it. And then this morning the car doesn't work.

I took down the original key and central lock thingy to try that just in case. No luck..

The mechanics spent 4 hours on it, running diagnostics with their tools, checking fuses, relays etc. They have said they can't find any reason why the car doesn't turn on.

The car has power when you put the key in. The car locks/unlocks from the key/button but when you turn the key to start literally nothing happens. There is no sound, no ticking or any sound of relays or fuses running or whatever.

The immobiliser is off, when you unlock the car the red light turns off and then I try to turn it on and nothing happens. I believe it isn't the immobiliser because, previously when I used to drive it, if I unlock the car and wait for the immobiliser to turn on and then try to turn the key the car tries to start up and then dies (I used to do this by accident when I first got it sometimes)

So I'm at a loss.

Tl;Dr car won't starts, started 12 hrs prior. Car has power. Keys unlock/lock car/disable immobiliser etc. But car won't run. When turning key there is no sound at all. Mechanics spend 4 hrs can't find what problem is.


Thanks so much if anyone can help I really appreciate it

 

[Fu Manchu]

About three threads down is another post about a similar issue. Attached with that is the pdf for fault finding start issues.

 

[Fu Manchu]

https://forums.justcommodores.com.au/threads/vz-adventra-lx6-ignition-issues.290414/

 

[Fu Manchu]

The growing number of threads with this issue often has a common theme. The car had low voltage.
We went through it too with one.

Carry a thick gauge wire with a spade terminal on each end. Use it to jump the car. (See multiple threads about this)
Over time we had to do this less and less.

The only thing I can think of is oxidisation on a relay contact somewhere. Neutral saftey switch or BCM or in the relay block or starter motor itself. Even though a flat battery is the common theme, that also goes along with the car sitting around for a while. That is what it is IMO. Oxidisation over time.

Removing the fuses for the ECM and BCM draining the capacitors by switching things on and then reinstalling the fuses. That might help. Might.

One technician suggested if the car had not been used in a while, the key might need to be re-mapped to the cars BCM. We didn’t think much of that and it’s not been done. Just got better with use.

 

[Not_An_Abba_Fan]

The neutral start switch hasn't died has it? Have they tried wriggling it in N and P to see if it starts?