[V8] Cluster woes

[Mike Arman]

> The V8 cluster is not at all like the 100/200 clusters and do not suffer from
> the cracked flexible trace problem they had.
> 
> Soldered connections do not normally fail - all cars have thousands of them. The
> only weakness I found in the V8 dash was the solid wire ribbon cables that
> connect the various pieces together. You could in fact have an intermittent
> there, but resoldering the connections is un-likely to fix it because the crack
> happens inside the molded plastic part where the "pin" attaches to the solid
> wire.

I had similar very symptoms on my V8 - fuel and temp gauges dropped 
sporadically to zero, came back with a whack on the dash pads. The pc 
traces were fine, the problem was cold solder joints at the pins that 
the interboard ribbon cables connect to.

These are assembled by "wave soldering" - does the whole pc board at one 
pass.

Problem is that if there's enough heat to solder the big parts (high 
thermal mass), it is too much for the ICs and other smaller parts and 
they get toasted.

I've seen this on other electronics equipment - *exactly* the same 
thing, cold solder joints on the large pin connectors - PC power 
supplies are good for that.

Cure is remove the cluster, take the boards off one at a time, and with 
a fine pencil iron, re-solder the bases of the interboard connection 
pins one by one. Put it all back together (now is also THE time to 
change all the burned out dash lights) and dollars to donuts your 
problems will be cured. I found four bad ones and some more suspect 
ones. You will be able to wiggle (as opposed to flex) the pins slightly 
in the pc board if the solder joint is bad. Also, a cold solder joint is 
"grainy" or "pebbly" instead of smooth and shiny. Use a magnifying glass.

Use some contact enhancer on re-assembly just as extra insurance.

I did mine almost two years ago, and that part (at least) has worked 
flawlessly since.

Best Regards,

Mike Arman
V8Q, lights, blinks, starts, runs (be afraid . . . )