Humidity and electrical gremlins
 

Does anyone know how humidity affects electrical components? The last few days it's been raining pretty consistently here, and I noticed yesterday that my tachometer (which has been dead for the last 6 months) suddenly started working again. And a couple of interior lights (which would power on whenever the engine was on), now work properly (only when the head lights are on). Does the humidity even have anything to do with this, or is it coincidental?

I can only give you my opinion as an electronics guy. Humidity does not affect electronics in general. Most electronics are specified for "95% RH non-condensing". Which is to say, as long as it is not actually wet then it's OK. I suspect it is just a coincidence.

Mike

Give your fuses a few spins.....then squirt some WD on the connectors
[ lightly]

While humidity may not effect a properly functioning circuit board, it can have a profound effect on marginal connections -- on a circuit board or on the connector leading to-from it.

The prime suspect in any intermittent electrical problem on a car is a bad connection somewhere.

I'd start checking grounds. (and fuses as Arthur suggested)

Just my 2 cents... arguably worth that.

Jeff Pierce