VZ won't start without help

[Titchin]

Hi, I was reading this post, seemed to be 99.9% the same as my issue. I've bought a 2005 VZ for a run about - Please read on.

I have a 2005 VZ Lumina Wagon Auto. The car had intermittent starting issues for a while then sat around for a few months, unsued. The problem has now developed into the SAME issue that you are having, only instead of being able to start the car for the rest of the day, I can only start mine for about 10 mins after jumping. If left any longer, the "jump" will need to be done again.

Reading these forums, everybody seems to develop a different issue with the way their car acts while starting, a different warning or code, a similar "no start" but will start when cold or a car that will start if cycling through the gears or or or etc etc etc.
So, I've guessed that ALL commodores, built with these BCM, ECU and PIM combinations, seem to develop issues, but the symptoms for each car are different depending on which of the 3 modules have gone faulty - or even the slip ring, oops, can't forget that issue either lol

so, as for my car -
Replaced Slip Ring
Replaced Keyfob
I have scanned the car TILL THE COWS COME HOME (and they are still not back yet)
- No codes and all good until "can't start" returns, and ECU sais "not present" wont scan but BCM etc will scan.
- Once jumped, fuel gauge error, reading empty until needle slowly moves.
I have replaced all relays, checked the wiring to relay/fuse hosing and checked with Multimeter.
New Negatives to the current earths on the vehicle - Strut mount Drivers side,,, rear of ECU (A few inches back, on side of motor) and onto ECU Neg.
Moved the ECU to another spot, as being on front of motor is a STUPID place - Y put something that doesn't like heat, I dunno, near a heat source :0

I think that's about it for the actual manual stuff.. I've "fault finded" with these forums, people having different issues but not identical, some people having what seems to be a "lower grade issue" like yourself, but doesn't seem to have developed to my full blown problem of a 10 min start window.

To the best of my Holden knowledge (NOT MUCH) I have narrowed my issue to a faulty ECU, as needing to jump the starter relay, the car runs fine, no codes, no errors and the ECU can be scanned. Put that down to one of the many relays or fine electronics in the ECU, giving pos or neg to whatever, once I've "jumped" the starter but not wanting too, on its own.
Occasionally after force start, I was getting a check powertrain error on dash, but since doing the new negatives, I haven't had that and could have been "anything", throwing the error.

Anyway, I dunno if all that above makes sense, sometimes I repeat and babble, but hopefully someone can help me, with something they have done different, but with the same issue and if it fixed it... - no point in talking about someone's commi that wont start because the immobilizer light is still flashing (slip ring or keyfob failure guys)

Thanks all

Everything you've done, I've done, and I should add, my car does not start all day , anymore, same as yours now , ten minutes at the most, I had a talk to one of our local auto electrician, he believes it is a common problem, tells me he can do whatever it is he does with the ECU, and everything will be good, I will let you know how it works out, just gotta come up with a few bucks, I will keep you posted.

 

[Fu Manchu]

Make sure the key is communicating with the BCM first. Don’t go unloading your wallet on something without supporting data.

Any technician can plug in an interface device and see this stuff.

What do you do if replacing/repair the ECM doesn’t work because it wasn’t the problem

 

[VZcommi]

Titchin,
Hmm, I'm sorry to say that I had a little laugh reading that it has now developed into the full blown issue mine is... I say funny as it confirms to me the same issue, intermittent at first, then goes full blown.. Apparently, the next move for our ECUs is to stop just whenever they damn well feel like it, I guess by cutting the fuel pump's power somehow - so looking forward to that problem ;0

So, anyhow, after a long search finding a ECU worth buying, and looooong talk with a ?specialist? ECU programmer, I have sorted a 2nd hand ECU and programming because nobody resets them before removal F%#@. I will keep u updated with the results of that trial when it arrives... See how we go.

Yes, would be good to know different ways to fix these ECU's - it must be a good business as I rang a wreckers in Vic, and a parts company -cooldrive -had bought ALL of their E55 ECUs.. Thinking it is for sure "common" being 15-18 yrs old. Rang them and they only deal with trade.

Fu Man,
Understand what you mean, and yes any fool can plug a scan tool in and try to work their way around, but no "fool" can match my level of determination for not letting something beat em.
Nah seriously, I've programmed a 2nd keyfob and neither has any issue with the immo, or never have seen a communication error that relates to the keys. After replacing the Slip ring, Errors are only there when the ecu loses it's whatever and needs jumping... I also forgot to say in the first post, I checked the ignition barrel's terminals and they are functional barrel end and at relays.
Being a computer issue, it could be 1 or more of many things - but there has been 2 other ppl of no start, jump relay and get fuel gauge warning etc on here, they replace ecu and all good now.... also people with different symptoms or errors (so maybe different micro relay blown) replacing the ECU. On that, and what I've already done, I'll spend 200 on a ecu n reset/prog and give it a shot too.. He's going to bench test it after re-programming, soooo, yeah, dunno. Worth a try.

Until then guys n girls.

 

[Fu Manchu]

Folks, you are heading down the garden path a bit.

if you are getting an ECU, what data supports it? I’m not talking about what is the car doing as an interpretive dance. I’m talking about what tests and diagnostic data has been done by people who should be doing it to support the repairs.

if your buying a second hand ECU, get a set from a wrecker. Don’t go buying just the ECU and going through expensive bull **** to get it working. It’s ludicrous.

if you get a set of keyhead, ECU, BCM, and security PIM you’ll pay about $200 and install yourself in 30mins (if you’ve never done it before, and 10mins if you have).

Expensive garden paths people, that’s what you are walking down.

 

[Fu Manchu]

If you want to know what breaks in the ECU, the inside is junk. There are really fine wires leading into the board that are the weakness, rather than the board itself.

They can be heat affected too, @wannaeatyourbrains found out in the MiddleEast and did a cool workaround by relocating the ECU off the motor (no wiring mods needed)

When you reprogrammed the key, was it a genuine key or a supercheap auto key using an obd based gadget?

This is the kind of process that should be used, and in this case it’s not the same issue but carefully and simply explains how diagnosing an ECU fault is done