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tachometer bounces when battery is charging
so my battery has been draining hard recently. i just saw that when my battery is on a trickle charger, the tachometer sits around 1.5k and if i take off the charger it falls back down to 0.

also, on a side note, not sure if its related. but if i turn on the turn signal switch and touch the turn signal handle and the chrome on top of the door panel, i feel a shock going through my arm.
that leads me to believe its a bad ground somewhere, anyone know where i should start looking?

also, the driver side headlight and turn signal arnt on the bright setting when being used. i.e. the turn signal is using the running lamps and not the turn signal filament when the turn signal is on.
Sounds like a bad or broken ground to me for the lighting issue. The tach issue leads me to believe you might have a bad starter solenoid, as the coil is fed 12V on the "I" post of the solenoid during starting. Charging the battery could have it backfeeding through the ignition circuit somewhere. Pull the 90* wire boot off the "I" terminal and see if the tach drops and your drain goes away.

You may have two different problems, a bad ground on the lights and a short in the steering column. You will need to use a meter that measures voltage, ohms, and amperage to troubleshoot.

I would run a jumper wire from the ground post on the battery to the ground point on the lights and see if that is the problem with them (bad ground).

For the battery drain you will need to measure the amperage of the drain and the remove one fuse or circuit at a time until you find what circuit is causing the drain. That will give you an idea of you need yo start looking.

Here is a good troubleshooting guide that covers in detail what you will need to do:

“If you can't explain it simply, you don't understand it well enough.”
--Albert Einstein
ok so i couldnt recreate the tach today. i also checked the volts and i could see .01 drops about every 30-60 seconds. i pulled the I cable and then the S cable multiple times, sometimes it seemed to work and sometimes i could see the drain still. im not sure, is it possible for the drain to be intermittant?

so just checked the amp draw on my battery with the car in the off position. theres no draw at all. so perhaps my battery just wasnt charged fully and gave me some gremlins. i left the battery on a trickle charger all night and hopefully i should be ok now.
Check to see if your voltage regulator is bad. It also needs to be properly grounded via the two attaching bolts. Often they are loose because the holes were overtightened.

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MeZapU;242739 Wrote:Check to see if your voltage regulator is bad. It also needs to be properly grounded via the two attaching bolts. Often they are loose because the holes were overtightened.

i changed out the voltage regulator earlier this year, it had the original on there.
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