How to fix speedo VS Commodore

[marvinstokes]

There have been many posts regarding Commodore speedos not working. Most of the advice tends to direct owners to either check their 'speed sensors', replace little internal cogs in their speedos or replace the cluster.

Having bought a cheap secondhand VS I was faced with the problem of no speedo and no reverse in the auto. I assumed that after I had replaced my transmission that the speedo would come to life, unfortunately for me, this was not the case.

Having nothing to lose I thought that i would remove the instrument cluster and have a look to see if anything was obviously wrong.

Having removed the cluster I took it indoors and inspected it. I was pleased to see that on the back there was information printed which gave me a clue as to where to look for a possible broken copper track. ( See pic 1 ) (Below.)

Using a multi-meter I started to check for breaks along, what I thought were, speedo related connections. these were:

Con 2 - Pins 2, 7, 8, 9, 10 & 11 ( See pic 2 ) ( Track 2 marked with pencil )

I used the meter set on 'Resistance' and checked for continuity from one end of each connector to the other. If I got a reading of 0 ohms then I new that that particular track was good. ( See pic 3 )

As i was thinking , "Why am I bothering to do this! " I suddenly got a reading of 1 ( Meaning an open circuit or break in the track ). ( See pic 4 ), this was on 'Con 2 / Pin 11' ( Pulse Ground ).

Narrowing it down, by carefully exposing the track with a razor blade and bringing the meter probes closer together, I managed to locate the exact area which was causing the problem.

Where the rear overlay is fitted to the back of the instrument cluster it was slightly oversized , only by a couple of millimetres, but, because of this, it had been trapped when the cluster was pushed into the dashboard. Over time the area had been eroded and the track had broken.

( See pic 5 )

How to fix it?

I couldn't solder the join as the heat would have damaged the plastic membrane even more!

I decided to try an old trick I once used on a computer keyboard with a similair type of break. I used a thin sliver of tin foil and, after exposing the break, again, using a razor blade ( See pic 6 ),

I sellotaped the foil over the break making a bridge.

I reinforced it with more tape ( See pic 7 ) before hastily returning to my car and re-installing the instrument cluster.

Guess what......? ~ The speedo works!!!

Not only that but the digital speedo function on the 'speed alert' panel also works. This suggests that the signal for the 'speed alert' comes via the analogue speedo. You can use this knowledge to check your 'speed sensor' function.

To get the digital speedo function, hold in both buttons on the speed alert panel whilst you start the car. Go for a drive, and if both are not working then it is likely that the speed sensor on the gearbox or the analogue speedo are not working. If the digital speedo is working, but not the analogue, then your speed sensor is ok but this fix-it is probably not going to help you because you may need a new speedo.

Hope this helps someone out there and I wonder how many people have thrown away speedos that could have been fixed using this simple method!!

Marvin. ( julie120bb@dodo.com.au )

[apoc585]

Fantastic write up. Well done!!

[fuzzy2308]

brilliant. great wright up well done will be very helpfull

[marvinstokes]

Thanks Apoc & Fuzzy for the feedback. This is my first post I've gained much from this site and thought it was time that I gave something back!

Marvin.

[DannyboyDS]

you can also get a conductive track repair paint from electronic shops for this sort of work, expose the track with the razor across the break and paint it up, then coat it with a clear nail polish :P

[HRVATSKI_VOJNIK]

mate thanks heaps, this saved me from a possible defect.

i always thought that converted speed alert speedo worked separate from the analogue speedo, how wrong was i.

the tracer that was broken was the same one in your thread, but on the bottom when it bends around 90*

i now i have a few layers of electrical tape around that area shouldn't happen again.

[egadgetjnr]

Hi guys, What abour where there are digits missing on the speed alert area. Like, for example. instead of an 8 it looks like an 8 without a top. Im thinking maybe the LCD isn't getting full connectivitiy?
Im about to buy a 1995 VS and thats one of the things wrong with it and i was looking at fixing myself.

[marvinstokes]

HRVATSKI_VOJNIK,
I'm very happy to hear that you got something out of my post. - Thanks for the feedback.
If you hear of anyone else with a dodgey speedo you'll now be able to give them the benefit of your experience! Cheers, Marvin.

[lucky lucas]

the damage to track 11 con 2 is same as mine but underneath, while i was careful taking cluster out and in , the problem was i did it 10 times kept checking speedo taking things apart, the needle part i thought i may have disturbed calibration when removing it, but this has happenned before, ive changed whole circuit board but it was scratched too , i will inspect to find best one, even get out the multimeter and check the tracks, so its imortant to be so careful when sliding cluster into dash, the back male plugs on the car must be secured in place with there clip in nature and you can feel them in with a push once they are located... but dont scratch the track, seems track 11 culprit with a few of us, about to do job now will let you know... cheers good about the speed alert too what an easy check for speed sensor....

[lucky lucas]

the damage to track 11 con 2 is same as mine but underneath, while i was careful taking cluster out and in , the problem was i did it 10 times kept checking speedo taking things apart, the needle part i thought i may have disturbed calibration when removing it, but this has happenned before, ive changed whole circuit board but it was scratched too , i will inspect to find best one, even get out the multimeter and check the tracks, so its imortant to be so careful when sliding cluster into dash, the back male plugs on the car must be secured in place with there clip in nature and you can feel them in with a push once they are located... but dont scratch the track, seems track 11 culprit with a few of us, about to do job now will let you know... cheers good about the speed alert too what an easy check for speed sensor....

....2 hours later, job done it works, lucky me, saved 50 on a new cluster , i scraped between two good points on faulty track, multimeter a must, and foiled it , taped it checked circuit , and sppeedo now works, odometer works thanks to new gear under stepmotor easy to do tricky part is speedo needle, while the signal was now there.. hooray... i had to refit speedo needle as it was too tight and jerked and dropped to quick, thought it was out and damaged but placed needle not so tight but secure. and now its sweet even matches the digital speed alert when that mode is selected. thank you marvin for the original post i spent all day but was worth it... cheers peter lucas

[marvinstokes]

Great to hear from another person who's not afraid to 'have a go'. Pretty good to do it all in two hours, it makes me feel good that my post has been of benefit to you and that you saved some cash!!...Marvin.

[marvinstokes]

Hi guys, What abour where there are digits missing on the speed alert area. Like, for example. instead of an 8 it looks like an 8 without a top. Im thinking maybe the LCD isn't getting full connectivitiy?
Im about to buy a 1995 VS and thats one of the things wrong with it and i was looking at fixing myself.

You will probably have to get yourself a replacement unit. The same thing happened to mine but I was able to get a second hand unit from ebay for $20. It is easy to replace, just two screws above speedo and then prise the facia off with your fingers. The old unit will push out towards you from the rear with a little bit of persuasion.

[minjayd]

You will probably have to get yourself a replacement unit. The same thing happened to mine but I was able to get a second hand unit from ebay for $20. It is easy to replace, just two screws above speedo and then prise the facia off with your fingers. The old unit will push out towards you from the rear with a little bit of persuasion.

gday, what if its in your trip comp, mine is missing pixels and can no longer read fuel useage, any ideas wether this can be repaired

[88GreenVN]

gday, what if its in your trip comp, mine is missing pixels and can no longer read fuel useage, any ideas wether this can be repaired

You will need to glue the mount screws in the trip computer. You have 6 mount tabs that hold in the LCD's nice and tight. They let go and the pressure is off and you get missing segments. When apart keep all the small plasic bits and glue back into place. I use the 5 min stuff.

[Troy5L]

great write up!!!!
my speedo has started bouncing again as in it wont work for 5 minutes after i start it up then it kinda bounces up and down, and once i hit the dash it will work again...so im definatly goin 2 try this

[88GreenVN]

great write up!!!!
my speedo has started bouncing again as in it wont work for 5 minutes after i start it up then it kinda bounces up and down, and once i hit the dash it will work again...so im definatly goin 2 try this

May also be the voltage regulator behind the speedo.

[Troy5L]

i took the cluster out just before, and had a look, nothing is broken and all is fine..

what do u mean voltage regulator 88greenvn? has it come loose, broken away? will i have to take the cluster apart to fix it?

[88GreenVN]

i took the cluster out just before, and had a look, nothing is broken and all is fine..

what do u mean voltage regulator 88greenvn? has it come loose, broken away? will i have to take the cluster apart to fix it?

Speedo out, tacho out if you have not pulled 1 apart before.

Then the voltage PCB will be the only thing you see looking at the cluster. Unclip the tag connector at the top and then pop the PCB out. Have a good look at the solder joints - all of them.

If your having issues with the cluster gauges - this is a good place to start and very very common issue with the clusters.

[wildeagle44]

thanks, very helpfull

[Sharkzz]

~S~
G'day all.
great heads up on the speedo fix. Got my wagon back from the doctors for rego and aircon and had found the odometer and the milage tick over not working (which it was befoer I took it in ) I couldn't be bothered with the hassle in talking to the guy in the repariers,so I want to fix it myself. I gather that the odometer and the milage works in tandem, what I would like to know is do they work on cable or electric ? and where does the info come from ? the motor or a cable from the wheels?. and is it possible to see a diagram of this. It's an auto wagon V6. I figure it was the mechanic or the aircon guys that have not plugged something back in or have loosened a connection somewhere.

great site and some exceelent help and info
thanks
Sharkzz

[strikewon]

GREAT POST...im another person you have saved time and money!!!!.....ive just driven it around the block about 5 times at first it didnt work but slowly became responsive...still a bit jumpy i will see if it gets better tomorrow..either way it has obviously solved the problem...could the fact that its jumpy mean i should do it again or should it just get better over time...it seemed to be gradually getting better buit i only drove for like 5 mins...im off to sleep....someone get back to me on this asap...CHEERS!!!!

[strikewon]

definate fix!!!

[customvlcommy]

thanks heaps for this have replaced 2 dash one harness and 4 sensors and all it was was a tiny break thanks heaps

[lloyd gibson]

Brilliant.....repaired mine as instructed, break at exactly the same place....GM really should fix this........it is bad design, not owners fault at all.


Thanks ever so much for your trouble!!!!!

[rolla83]

Hey, so how do you fix the 3 level display leds dieing in VS Stato cluster? is there anyone that know how to replace them?