Instrument Cluster lights MY

[David D]

Hi

I have a problem with the instrument cluster lights in my '87 Brumby. Basically, they no longer come on with the headlights.

The problem started after I went in to try and fix an intermittent gauge / warning light issue. I'm not sure how but I ended up with the gauges / warning lights working but the instrument cluster lights no longer come on with the headlights. So I basically 'fixed' one thing and seem to have somehow caused another issue.
I was messing around yesterday and I reckon there's power going to the (12 pin?) plugs at the back of the cluster and my test light even showed power where the bulbs screw in. I swapped a bulb with a definite working one just incase but still no luck. The heater controls in the middle still work it's just the lights that illuminate the speedo, clock etc that don't work.
I'm outta my depth now and just wondered if I am overlooking something or if anyone has any advice.

Cheers

David

[TOONGA]

You may have cooked the circuit board on the back of the cluster. it can be fixed but you need to be handy with a soldering iron.

TOONGA

[Proton mouse]

If you can, pull the brown multi pin plug off the back of the cluster (one behind the clock) and test pins 11 and 12 (one red wire with blue spots and one red with
green stripe) which are the pos and neg feed for the illumination of the dash. You must still have the main light switch plugged in and turned on.

If it has power, then it is probably what Toonga has said. Then pull dash out and visually check the 2 outer most tracks that
run right around the outside of the circuit board, which feed all the illumination bulbs. If a track is broken or
fried, then scrape away a little of the green resin (enough for a solder blob) from either side of the broken track, and solder in a bridge of suitable wire.

Good luck!
John.

[David D]

Thanks guys, I did actually scratch the back of the cluster refitting so I've probably damaged the circuit.
This might be a stupid question but.....

There used to be a conductive paint you could use to repair heated windows. If I have scratched the circuit, could this work to repair it?

Just a thought. If not I'll try soldering - it's not my forte but I'll give it a shot.

Cheers

David

[Bantum]

Hi David,

As long as it's not a deep scratch & there's no crack in the board, worth a shot - you still have to remove the top coat of sealer though.

You'll also have to remove the cluster to get at it properly, so take a few photos while your at it - to show us the damage ...

In my opinion - you should just go with soldering, much easier & relatively quick if you know how to do it correctly ...

Tip : If you are using a soldering iron, get it nice and hot first ( something in the 400 - 450 Degree range ) & don't heat up the track for too long or it will delaminate it ...

Cheers, Bantum ...

[David D]

Hi guys

I went into the abyss yesterday to try and restore some light and this is what I found on the back of the instrument cluster.....



Seems I was a bit rough on the re-install.

I scraped off some of the green stuff and the track looked remarkably clean and intact so, just out of curiosity, I plugged it back in and..... there was light! So, I put the soldering iron away, put the dash back together and went back in the house. Can't exactly claim I 'fixed' it but let's just say it doesn't seem broken anymore. Hope it stays this way. This is what it looked like cleaned up:



Thanks for the help. I would never have figured out where to look for the fault.

David D

[Proton mouse]

Hmmm that's a bit of a mystery as to why you had no lights, the copper tracking is fine, only some scratches to the lacquered finish, which
wouldn't have affected it, oh well at least you have lights now!!

[coxy]

The rheostat on the back of the dimmer circuit for the Instrument lights often also causes this type of problem as well