Wierd Power Issue

[stevedyndiuk]

1979 Super Beetle convertible. Stock FI system. Drove the beetle one day to the mailbox, upon returning to the car, there was no power, no lights when I turned the key.


The first thing I did was swap out the dual relay for a brand new one, and that changed nothing.

I attributed this to a bad ignition switch and replaced that. That also changed nothing.

The thing that struck me odd, is that once I replaced the ignition switch, I tried to crank it, and there was no power to the dash, but I could hear the fuel pump running... with the key off. I pulled the ignition switch connector off all the way and the fuel pump continued to run. I put it back together and walked away and came back 10 minutes later and it started right up, everything looking normal on the dash as far as lights etc. I turned it off and tried to start again, and no power again with fuel pump running.

When it decides it wants to start up, it starts no problem. So I'm leaning toward a failing component or bad connection or short.

The wiring is largely unmolested in this car, and I have replaced spade connectors here and there where needed. All my fuses are in good condition from what I can tell.

What am I seeing here? A short somewhere? A bad ground? A bad voltage regulator? A different bad relay somewhere else? This car was running 100% before this foolishness started. I have been looking at the wiring diagram for this car for days now and am going cross eyed.

Any insight would be much appreciated.

[VW_Jimbo]

Stop looking at the diagram. That was a joke. You need to know which wires to look at.

You need to look at the car. Specifically all of the connectors with red colored wires. I, personally, would start with looking at the battery. If suspect, pull the cables and clean them and the posts. Then to the starter solenoid, then to the connector under the back seat, then up at the fuse panel (8 & 9 if I remember correctly) ignition switch and well, I am not recalling, but just keep cleaning.

Once done, throw a test light or DVOM in the trunk. The next time you loose power, start testing.
_________________
Jimbo

There is never enough time to do it right the first time, but all the time necessary the second time!

[Starbucket]

Are you saying the fuel pump is running day and night? if so I would start there looking for a shorted wire or does the fuel pump turn off with the key is on? When was the last time you cleaned the trans. to body ground strap? that's how the motor grounds to the battery.

[stevedyndiuk]

VW_Jimbo, Starbucket. Thanks, I'll take both of those posts into consideration, these are the exact type of tips I am looking for.

The fuel pump does shut off eventually, I think it must be a short because when the fuel pump stops, the car will usually start up.

[stevedyndiuk]

I found the issue!

Turns out the ground that the battery uses was bad. There was a ring terminal on the end that connects to the body, that looked fine but was not fine.

I went to try to start the car and could hear crackling, reached back and the ground strap was hot, the ring terminal was broken and the end of the cable had been painted over a few times and was stuck there but the electrical connection was bad. I fixed it temporarily and have new parts on order.

Thanks for all your suggestions.

[Starbucket]