The Forgotten On

Alright, so I just installed my new PCB after the old one stopped working.

The gas gauge was pegged ( I know I don't have a full tank) and the warning lights had a split second delay before coming on.

Then the smoke came wafting out from under the dash.

All connectors were connected to the correct connection with both fully populated ones connected to the bottom connectors and the one missing some connections attached to the back.

Here are some pictures. Does anyone have any idea what could have happened?

GregBBRD

Yes.

Actually have had that happen, in the shop.

It's possible to install the bulb sockets so that they short directly over to the ground side, instead of the power going through the bulb. Burns up the power side of the trace to the bulb really fast.

I make sure the guys check the bulb sockets really carefully, before turning on the power, now.

upstate bob

dead short in the board? I hate those things. VW had, for a while, layers of them sandwiched together.
Car would act dead sometimes until you pressed on the stack and the panel would come alive.
Can you find the errant burn spot?

Ducman82

had that happen as well. ended up having to run a wire in its place. as greg said, bulb sockets suck

OTR18WHEELER

I may have a used one for sale after this weekend.
$120 + shipping for the whole cluster,
as is.
'79 Porsche 928 instrument cluster


'79 porsche 928 inst cluster pc

.....cue randyv

The Forgotten On

I'm saying screw it at this point and taking it to North Hollywood Speedometer to let the pros deal with it.

Will update when I install it.

Speedtoys

I'll buy it.

The Forgotten On

Finally got the issue resolved for now.

$700 in new circuit boards and a $400 service by North Hollywood Speedometer which included all new bulbs bulbs (don't want to touch it for 37 more years) , rebuilding the speedometer motor, and recalibrating the damned thing and it should work.

I have the day off so I will fit it and hope for the best. All in all it cost me 3X as much as I thought it would have and I could have probably bought a new cluster from Porsche for that.

Eh, c'est la vie...