Electrical Problem - '69 Delta 88 Custom

[Guest Mixter755]

Hi, I have what seems like an open curcit in my Delta 88 whenever I allow it to sit a few days between starting the battery runs down. I do not know if there is a corrolation but my fuel sending unit and my clock also do not work.

Last month while I was working on the clock I shorted out the fuse and during the time the fuse was out the battery held its charge. Any assistance on how I can find the problem?

Thanks

[joe_padavano]

Hi, I have what seems like an open curcit in my Delta 88 whenever I allow it to sit a few days between starting the battery runs down. I do not know if there is a corrolation but my fuel sending unit and my clock also do not work.

Last month while I was working on the clock I shorted out the fuse and during the time the fuse was out the battery held its charge. Any assistance on how I can find the problem?

Thanks

First, an open circuit is exactly that, the wiring is open, meaning that there is no connection. You have the opposite problem - a short circuit that is draining the battery. Unfortunately, it can be anywhere. You need to study a factory wiring diagram and try pulling fuses one at a time until you find the one that was causing the battery to discharge. Once you've isolated the circuit, then trace the wiring until you find the source of the discharge. It's time consuming but this is about the only way to do it.

[Guest rsd9699]

Check the alternator for a shorted diodo.

Ron

[rocketraider]

A shorted alternator diode usually shows up as a GEN light that stays on with the key off. But, nothing is above suspicion.

The fuel gage feeds off the TRANS-GAGES fuse so kinda rules that out for a battery drain with ignition off. I suppose a bad alternator or regulator COULD allow a backfeed thru the dash cluster and fuel sending unit to ground.

Since the condition went away with the clock fuse out that leads me to believe it's related to that circuit. It is unswitched (hot at all times) so anything on that fuse can cause a battery drain.

There are two load side feeds on the CLK-LTR-CTSY fuse. One leg feeds the clock, dash cigarette lighter, dome lamp, glovebox lamp, and trunk lamp.

The other leg feeds the underdash courtesy lamps and map lamp if equipped.

I would remove the bulbs from the glovebox and trunk lamps and see if the battery drain stops. Pull the cigarette lighter out of its well too while you troubleshoot. If it stops, reinstall the components one at a time until the trouble returns and you've found the cause.

There's always the possibility you have a bad battery.