Temp gauge, goes hotter when I turn on the lights.

Hey Guys and Kelly, So tonight as I'm heading down to sunset point I noticed when I turn on my lights (after the car has warmed up, and the gauge is reading in the middle) the temperture gauges goes up a fair amount. I'd say the jump was 1/16 inch. I know my original si batteries are probally shot and I guess this is proof, right?

Can't wait to take that rats nest apart! Can anybody run me through the process? Please....

Cheers, Rick 1988 325is/5 235K

It may only be a voltage difference due to the extra drain on the charging system...Might be as simple as a ground wire being corroded. Might come in handy on a hot day to cool the car by turning off the lights...(LOL).

Does the same thing happen with other electrical loads? Heater, brake lights etc? Perhaps a volt meter on the battery and monitor as loads are turned on and off. Might be a failing voltage regulator.

Bob in Lake Havasu



Edited 1 time(s). Last edit at 09/23/2012 09:51PM by Bob in Everett.

Quote
Bob in Everett
It may only be a voltage difference due to the extra drain on the charging system...Might be as simple as a ground wire being corroded. Might come in handy on a hot day to cool the car by turning off the lights...(LOL).

Does the same thing happen with other electrical loads? Heater, brake lights etc? Perhaps a volt meter on the battery and monitor as loads are turned on and off. Might be a failing voltage regulator.

As Bob said, probably a bad ground connection somewhere on the dash or instrument cluster. It acts like putting a resistor in series with everything. Watch out for corroded or loose connections, before pulling apart the SI batteries, not all evil in the world come from them!

Quote
rkj
Hey Guys and Kelly,

Very good one!

Rick, Pelican Parts has an excellent step by step with pics for r&r SI batteries.

alan