Electrical woes

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update...

I got my starter rebuilt and it works fine but I am still not getting power to start the truck. I don't get it!! I only have power to the brake lights, harzard light on the dash and a click when I turn the key. all my grounds are in their proper locations. am I missing something.
 
What is the voltage at the starter solenoid black wire w/white stripe when someone is holding the key in the start position? What is the voltage at the fuse block when you turn your headlights on?
How do you know the starter works fine? Did you jump between the battery cable and the black/white stripe wire to try starting it?

If you can answer these question we can narrow down the possibilities.
 
wiring checks

Really, I think you should get some help before you fry something--you spliced partial harnesses together If I read correctly are you sure you did that right?

doing all these checks with power on is risking frying the wires when you do get power

One alternate way to do this is to use the OHM function- make a jumper wire or use a croc clip and verify each power wire is running correctly.

First disconnect the battery

set the multimeter to ohms (OMEGA SYMBOL)

You do this by taking one wire and clipping the jumper to it and taking this to ground on bare metal anywhere on the body/frame
the other end of the wire hold the red lead on the wire and the black lead on the frame---you should read less than 1 ohm probably .1 or even zero

0.L means open loop and a broken wire

next disconnect the ground jumper and you should read 0.L if not the wire is shorted to ground

you can do this with wires splitting off to multiple connectors but check one end to all the other ends for continuity

also two wires that are not both connected to a ground or common component should not read resistance with a probe on each wire--that's a wire to wire short

There's limited wiring on the FJ so this shouldn't take long


The click from you solenoid means you actually have ignition power to the solenoid and either the solenoid is bad, the battery is dead, or you are losing the power through the ignition switch

You can bypass this using a remote starter connected to the solenoid--this is easier than the screwdriver across the terminals and doesn't make you jump from the sparks

The ohms check will tell you which fuses are good and bad too---put a lead on each end of the fuse and you should have low resistance through them


if you do ohms checks on a live circuit you will probably blow the meter fuse.


Since you're battery is probably bad I'm concerned that you may have something shorting and drawing it down--if that is the case it must have enough resistance (like through a component) to allow it to slowly drain the battery--a direct short would smoke wires

if you must press on by yourself do some reading on electrical safety and performing continuity checks.

Don't be intimidated by the schematic just start shooting end to end and verify what you can one wire at a time

You also mentioned moving grounds---grounds need to go to clean metal not bolted to a painted or dirty surface

Best of Luck
 
There are a couple of negatives associated with using an ohm meter to diagnose an electrical problem like this.
1. You have to disconnect the battery to make meaningful measurements.
2. You need a high quality meter because the difference between < .1 and 1 ohm can be the diffference between bad and good. Cheap meters don't read this accurately to tell the difference,no matter what the numbers say on the display.


A simple test light probe is just as good and is easier as you don't disconnect the battery.

If there was a serious short in the wiring, he would have run across it by now. The problem is a lack of power or a bad, high impedance connection.
 
ohms

Yes a test light will work fine and remove the dangers involved with using the vehicle battery

Accuracy of ohms not that important unless you are looking for something very specific like in electronics or the resistance of a coil or maybe in the FJ a resistance wire

I'm just talking about shooting for shorts and opens, they will be obvious at nearly any accuracy.

A high resistance short will drain the battery and not be obvious--only the low resistance ones are obvious---like said in the post---they let the smoke out.

Just my 2 cents on safety since I do it for a living on aircraft we follow a lot of rules others might see as anal but our parts can cost as much as any 10 cruisers you've ever seen sometimes:eek:
 
ok a couple of things. all those spliced wires have since been removed and replaced with another harness. also the battery is a month old and I use it in my 87' and its my test battery for the 40.

tonight I turned on the truck and testsed the fuse box power and I have it, I have power to the starter as well. now I did test the thick black wire with a white stripe, now I assume that wire is connected to the ignition and with that wire removed from the starter I have no power to that. I did test the other wire, the one to the oil pressure and that had power. could I be looking at a bad ignition swith?
 
Yes, it could be a bad ignition switch. It could also be bad wiring going to the switch, which is why I asked all the specific questions about what the voltages are in the fuse block and at the starter when you turn on the switch.

Based on the answers to the questions I asked, we could narrow down the problem, but if you can't supply answers, then just go ahead and replace all the wires from the battery to the ignition switch, the switch and all the other wires and the problem will go away.

Don't confuse voltage with power. If you measure the voltage on a bad circuit wire with the wire disconnected, it will show battery voltage, but if you hook it up, the voltage will drop to zero because there is a high resistance connection somewhere upstream that won't pass any power.
 
HOLY CRAP!!!! Got her started....turned out to be the ignition swith. The previous owner replaced the ignition key and in doing that when you plugged the round part of the ignition swith in that metal t inside the column and the groove wouldn't line up. But i got her started and she ran then died but i couldn't be happier.

Pin Head as well as everyone else that put up a post on this thread i want to thank you for all the electrical help. I learned electrical work for the first time and i understand the truck alot more too.

Jason
 
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