Dash not working after car left out in the sun?

[RangerJ]

Hi all

For the last 12 months, in very hot weather when left out in the sun, my 2002 Auto VX Execs dash stops working - all the gauges sit at 0 (and whilst driving the speedo and petrol gauge move up and down quickly in the lower ranges but never up to the speed I'm doing or the amount of fuel actually in the tank), the electronic part of the dash just sits on 260,000 (which is the next due service), pressing the Mode button does nothing, and both the indicators are lit up as though the hazard lights are on, but not actually flashing.

The very first sign of this issue was when on occasion the fuel gauge would stop working (didn't seem to be affected by outside temp though as first happened at night in the pouring rain), example it was showing I had half a tank but was in fact empty.

Then in the hotter months very occasionally I would have the issue I first described... Now EVERY hot day when the car is left in the sun, it's happening. If the car is left in the shade it's fine, even if it's 44 degrees like Monday last week, it's only if it's left in direct sun.

Once or twice last summer when this was happening, if I stopped at a set of lights the engine would cut out, but would start again without a problem when I put it back into Park. Prior to it cutting out it felt low on power, really sluggish, kind of like a manual in too high a gear. I haven't had it cut out again as yet.

I did have the RAC out once when this was happening and he believed it was the alternator, but 2 weeks later I took it to get serviced and they said the alternator was absolutely fine and as they serviced it first thing in the morning, the issue wasn't happening as it hadn't been left in the sun long enough to replicate it, and they couldn't find anything wrong from my explanation of the problem.

I love this car and don't want to get rid of it but I'm close to losing my license after getting bloody speeding fines when I've had to drive home from work with no speedo!

ANY ideas?! I've finally bitten the bullet and booked it into Holden for a service but for $450 JUST for the service alone I'd kind of like to find out what the problem is beforehand if possible, the car is physically not in the best shape, a couple dings, quite a bit of rust etc and therefore as much as I love it I'm not going to spend thousands of dollars on getting **** fixed, so I'm hoping this is something simple.

 

[Brisbarnz]

Used to happen to my vy, I started using a sun shade on windscreen through the day and it stopped playing up. I don't know why the fuel gauge is affected though.

 

[FXST01]

If it was my car I would be looking for dry solder joints in the dash. In my VP, the power windows would never work if I parked the car in the sun on hot days, I would have the doors open and have the fan on, and when the inside temp dropped they started working, so I took the window module out from under the dash and resolder every joint, now it works all the time and has for years.

 

[devilly]

do you have a dash matt ??

 

[RangerJ]

Thanks for the replies. Yes, I do have a dash mat and I also use a sunshield whilst I'm at work and it's outside in the sun, but it doesn't make any difference.

The car is in at Holden today, from my explanation the chap believes it's the BCM that is failing, which would make sense since a couple years ago my headlights stopped turning themselves off automatically, but then suddenly started working again.

He said this will be around $1,000 bucks to replace as it will then need 2 new keys coded, blah blah blah... so my next question is, if this is definitely the problem, should ANY mechanic be able to do this job (ie should I call around for quotes) or will I just need to front up with the cash?

 

[RangerJ]

I should probably add I have ZERO mechanical/car knowledge, I know how to check the oil and water and that's it so I won't understand any mechanical lingo!

 

[sleepa]

If you could find a second hand working BCM with the keys that would be cheaper.

Just get a mechanic to swap over the BCM and change the key heads (I think), and it should be good. Someone else feel free to confirm/or correct this.

 

[Growley]

A quick look on Ebay for "VX BCM" shows second hand BCMs with a key selling for $50. You need to make sure the BCM is correct for your type of vehicle.

I haven't done this kind of repair but I would do some more research then probably try this on my own before spending a grand. Obviously the risk in replacing with a second hand part is it may fail sooner than a new one.

 

[devilly]

i got the bcm and key and ecu matching set and swapped it over my self ,you will need a day to install if your not a handy person.its easy as ,only hard part is the clips, this is what was in mine and why it wasn't working properly...i would start at the ecu passenger side....drivers side a bit harder as it's up under the dash....if your not used to this type of work say 1 day to do it and 1 day for recovery on your back...

 

[RangerJ]

Thanks all. I wouldn't do anything myself, I'm a 27 year old female who had to call the RAC to change a tyre good news is that it's not the BCM after all... Whacking the top of the dash fixes the problem so at this stage it appears to either be a faulty dash cluster or at best a loose connection somewhere. They're going to take the dash apart and have a look then let me know what the verdict is.

I suspect the issue with the engine cutting out those couple of times (it hasn't done that in over 12 months) must have been an unrelated issue, but since it's been so long since it happened I don't think it's worth looking into at the moment. Obviously whatever caused it won't have resolved itself but if that happens again I'll cross that bridge when I come to it.

Other than that no other major work needed which I'm really happy about because I was anticipating she needed a lot more work done than she is worth and I didn't want to be faced with "Do I or don't I spend the money?".