Weird Electrical Problem
 

:confused:I've got a nice, charged Optima Red Top that always started her up, but recently, I haven't been able to. I've checked connections many times over, but obviously I'm missing something. When I connect the battery (or jumper cables from working car), I can turn any and all accessories on and they stay on nice and bright; fuel pump surges to life, etc. As soon as I try to engage starter, everything goes dead, like a circuit breaker tripped. I say circuit breaker, because if I disconnect the battery and try again tomorrow, the same cycle will happen. I haven't figured out the minimum duration that nothing works, but it's more than an hour yet always works the next day. Anyone point me in the right direction?

Sounds like your transmission ground strap is broken or not connected.

I'll check that. I replaced it when I replaced clutch a couple years ago and I gave it a cursory glance today, but I should give it a good look. Why would that allow the accesories to work until starter engaged, then essentially kill the whole system for ~24 hours? Maybe the Voltage Regulator is shot?

Bruce - the voltage regulator won't cause this problem. Sounds like you have a high resistance connection somewhere that "opens" when a heavy load is placed on it. Check the ground strap as suggested but also look at a both battery cables from one end to the other. Take all the connections apart and clean the contact surfaces. A bad battery can also do this, maybe a local parts place can load test it for you.

I would suggest hooking up a remote starter button and that will bypass all the starting circuit such as the switch, wiring, relay board, etc. If the starter spins then something is wrong in the part you jumpered around. I am thinking it sounds like a shorted starter or solenoid to me.

You have some oxidation between some connections between the battery and the starter. Try this: when it won't start up, keep a load on it like the lights then get a multimeter and measure voltages between the battery terminals and the starter.

Measure voltage from battery POS terminal to POS battery clamp. should be 0V. If > 0.1 volts, remove clamp and clean clamp and POS battery terminal.

Measure voltage from battery NEG terminal to NEG battery clamp. should be 0V. If > 0.1 volts, remove clamp and clean clamp and NEG battery terminal.

Spoke

Hi, I would also add, use di- electric grease, on clean connections. It conducts electricity. DC voltage likes clean connections. Any time you have several problems that are electrical and erratic, look for a grounding problem. You've checked the battery connections, check the connections on the starter. Just bought a starter on a truck because dirty, loose, connections, melted the stater. I'm an electrician for many years and auto- electrics can be tough to diagnose for me. Hope this helps. LB

When you add a battery through a jump start or other battery. You are offering a ground to your system. I believe this is why your systems now work on your car. Any ground you add, will not hurt anything. I added a ground to a Fiero I had. It went from the engine to frame. A couple of twisted # 12's, and two crimped terminals. The engine ran better, and other systems were improved. LB.