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lights on without any fuses- Any suggestions

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Thor

Thor

Senior Member
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Question: My lights and flashers come on when I have everything disconnected from the fuse box & 2 in line fuse holders. Is that normal?

I found this when trying to fix a major short that occurs whenever I turn the ignition key to the start position. There's a click and everything dies. If I disconnect the battery and then reconnect it I have power to everything until I turn the ignition key again.

I don't know if the two things are related or not.

If I leave the battery hooked up and there is a constant draw on it, it goes dead in a few days. Should the headlight switch be drawing power all the time?

When I look at the schematics it appears that the brown wire goes directly from the light switch to the starter solenoid, which then goes directly to the battery. If I disconnect that brown wire I have no power to the headlights.

Any thoughts or suggestions would be really helpful.

Thanks
 
Lights are not fused on most early LBC's. Normal.

Sounds like a solenoid or starter issue. At least that's where I'd start.
 
I know this doesn't completely make sense, but that kind of problem is often simply the battery terminals. Give both the battery terminals and the connectors a good cleaning with one of those tools specifically designed for it, and while you're at it, make sure the connections to the chassis and starter solenoid are OK too. It often happens that a dirty contact will behave this way; I'm not sure why. It seems possible that, when the contact is just barely being made, the surge of current to the starter fries the contact and you get no more conduction until it's disturbed. Or maybe it's from mechanical vibration. I dunno. I just know that weird stuff happens when you're dealing with high currents.

As for the second question--if you are drawing current from the battery when the ignition switch is off, there is definitely a problem somewhere. If you can find or borrow a high-current ammeter, hook it up in series with the brown lead from the battery and make sure it really has a current drain. Then, disconnect things until it disappears, and you'll know where the culprit is. Good chance it's the regulator box, possibly the cutout relay is not opening. But I suspect that this is a separate problem.
 
You can just put a test light between the ground terminal of the battery and the ground post on the battery. If it lights up, current is flowing. If it takes a few days, I suspect it is a small load. Start shedding load with the test light connected. (pulling fuses is how you do it on most cars, with an LBC it could be a bit different as some loads aren't fused) When the light goes out, you got it.
JC
 
I replaced the battery 3 months ago and it holds a charge if totally left disconnected. Since I have disconnect almost everything it doesn't seem to have the constant drain now. So I need to slowly add things back and see when it reoccurs.

The short is so weird. It's there and then gone. Could the starter solenoid be bad? Work one moment and then not the next? Then again I think it may not be that either as I have the following symptoms:
1. When I turn on the dash lights using the light toggle switch all the dash lights come on but if I turn them off using the switch and then turn the ignition key to the accessory position all the dashboard lights come on, even though light switch is off.

Now if I turn the ignition key to start I get the click and everything dies until I take the battery cable off the battery. So there has to be some feedback or something. I just can't figure where. The dash lights have "Red/White" and Light toggle switch has "Red/Green".
 
Your car has lights in the boot and glovebox... with switches. Go through the proceedure Steve suggests.
 
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