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How to troubleshoot this electrical problem

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Thor

Thor

Senior Member
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I recently changed my starter solenoid as it was no longer working well. I also had removed the dash to repaint the cowling.

Initially I had problems getting the starter to kick over but after starting to trace wires under the dash everything started working? Loose wire perhaps? I couldn't see or find anything. Two nights ago I heard a snap and everything went dead.

Initially I had the battery red light come on when I turned the key to power and thought it was the starter solenoid issue again. I started tracing the wiring to the solenoid and had current to where the white/red wire went into it but no power at the starter solenoid hookup where it goes to the starter motor (No current when I turn the key to start position). So I thought ok just a bad china made solenoid.

However I am finding that if I turn the key on (just to power) so the battery red light comes on and turn anything on such as the turn signal, fan switch, etc everything goes dead.

My question is am I looking at two different problems meaning bad starter solenoid when I do have power up to the starter hookup and some short or something else under the dash to complicate things or could it be all linked together.

And where would one start to trouble shoot when everything goes dead whenever any switch is turned on? Thanks
 
Thor said:
.....
And where would one start to trouble shoot when everything goes dead whenever any switch is turned on? Thanks
Click to expand...


at the battery.

sounds like you may have a loose connection somewhere. perhaps a bad ground.


mark
 
Well when all is dead you check with an ohm meter. Connectivety.
 
Ok I have worked through the following:

i installed a new battery and fully charged it just a week ago. I've placed it on the charger and its fully charged at this point.

When I connected the lamp between the earth terminal and the car, lamp remains off

When I connected the lamp between the purple wires from the fusebox and the +ve terminal, the lamp stayed off.

When I connected the lamp across the purple and green wires at the fusebox, test again - the lamp came on = fault on the ignition switch or dirty connectors.

So I switched to different ignition switch from my 1275 parts car. Had the same experience = Power on until I turn key to starter position then entire system goes dead. So my guess is that the first ignition switch isn't bad but something else.

I've traced the white/red wire that hooks to the starter position and tested both current and integrity up to the starter solenoid. I have it but not beyond which I would expect until I turn the key to the start position. The problem is once I turn the key the entire electrical system dies. So could a bad starter solenoid at that connection actually kill the entire car circuity? I don't even get power at the fuse box once the starter key is turned.
 
Does the starter turn if you go directly to it from the battery? Bipass all the switches and solenoid.

That snap you heard was something, a hot wire, going to ground in my opinion.
 
Jack's idea is a good one. Try that. Also try disconnecting the starter entirely and see is the power still dies. My feeling is that the starter is
distracting you from the real issue, which is still to be found.
 
jlaird said:
Does the starter turn if you go directly to it from the battery? Bipass all the switches and solenoid.

That snap you heard was something, a hot wire, going to ground in my opinion.
Click to expand...

I agree Jack,on both the starter and the hot wire.

Stuart. :cheers:
 
Those symptoms sound awfully familiar from the dim and distant past! In my case it WAS a dead short in the starter!!!
 
Yes, Mike,that can be the case.And usually means a replacement starter.
I suppose connecting an Ohm meter across the starter would show that pretty quickly?

Stuart. :cheers:
 
Yep, it would Stuart. That would be my reaction but then the other way works if you don't have one or know how to use it.
 
I thought I resolved it when I had lifted up all the fuses from the fuse panel. I still got a spark when I connect the terminals to the battery so I was thinking, God what is still connected. I have a trickle charger hooked up to the (+) terminal and so I removed it. No spark and when I turned the ignition key I had power and the starter turned over.

So I figured that was it. I reconnect everything and once done nothing. Battery was dead. I hooked up a regular charger and charged the new battery. When it was almost fully charged I hooked up the cables and kept charging. Everything worked except I noticed that even with the charger on the battery was being drained. Man is this frustrating.

So maybe I should remove all the fuses, see if the battery still gets drained. If not slowly connect each fuse and see what happens. Thought about this approach?
 
Sounds like a plan I would use.
 
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