86 toyota no dash lights and wont start
 

I have power going from my battery to my fuse boxes bowfin cab and under hood and power goes to my ignition switch but when I turn the key nothing happens. Bought a new ignition switch thought that it was bad replaced it and I'm still having the same issues. As far as diagnosing it I have checked grounds, both relays by IN cab fuse cluster, the starter relay and make sure the terminals are tight with no corrosion

You know, I didn't hear the word ... multimeter.

You have an electrical problem. You can try visual inspection of grounds and terminals, but those gosh-darn electrons are just so small! You need to find out where you have power and where you don't.

How much did you spend on that new ignition switch? It might have been more than a multimeter http://www.harborfreight.com/7-funct...ter-90899.html, and the meter would have saved you from spending the money on the switch.

Second what Scope says^^^

Plus you need to describe what truck-year-model you have.

I have an 86 Toyota Pickup 4 wheel drive. The thing that is really been trippin me out if I have power running into my ignition switch and if I connect the power terminal on the ignition switch to the power terminal for the accessories all my accessories won't turn on but otherwise they stay off same thing with my starter and this is the second ignition switch that I've bought. I thought for sure the last one was bad when it was doing the same thing that this one was doing. I have checked and make sure there is continuity through my ground cables and they have all checked out.

It also has a carburetor swap on it I took out the fuel injection system and put in a Weber carb

accessories will NOT turn on, but otherwise they stay off.
meaning either way they stay off.

What is the "power terminal"? All pins on the ignition switch are power (as opposed to ground) terminals.
Care to show us on the schematic where you found power and where you did not find power (voltage) where there should have been voltage?

Attachment 114423

Okay so white and red has 12.67 volts and the white only has seven and a half volts I trace it all the way back to the fuse box and it's not a problem in line so I'm kind of stumped on where else to go

Your 80Amp fusible link that looks like a fuse cartridge ( and that all those white wires connect to) must be blown or connection to it broken. Need to probe both sides of that FL. Do not force it to remove. Try to see if possible to probe both supply and output side of FL first. If you need have no access to test point as fuse block is right now, you'd need to un-mount fuse block, and access from below.

Your meter has such high internal impedance (it draws nearly no current to measure voltage) that you can have a very high resistance connection (a broken wire with a microscopic connection?) and still measure the voltage "on the other side." But as soon as you place ANY load on that wire, the voltage drop across the high resistance drops the voltage to nothing. In that case, you can measure a wanky voltage (7.5?) that's almost meaningless.

The easy way to test that is with a "test light" that has a small incandescent bulb. It doesn't pull much current, but enough to reveal that you don't really have a connection.

Your case is much simpler; the white wire only has two ends! Trace it back to where the voltage changes, and look there.

O.P.,
Like ^^...
or put switches in position that should make the the parts you're having a problem with come on. Then take your voltage measurements.

I finally ended up finding the problem on the main alternator line. It breaks off and splits into a few other wires about two feet into the wiring harness. This runs all accessories in the rig. It was corroded and broke so all I had to do was replace the connection and everything is good

Glad you found it.
I believe, that's where the thin white "S" wire taps into the thicker white "B" alternator-to-batt wire, correct?. That kind of splice is problematic, gets corroded and/or brittle. (Another splice similar to that causes a coming problem is where fuel injector wires crimp together near/under the intake manifold.)

That is correct. Just wish I could have found it sooner lol

Yes but it is much easier to just keep replacing parts and hope you get lucky.

Then do the trouble shooting and find the problem.:coffee:

Years ago I had a friend that just could not get his electrical system to work.

Spent hundreds of dollars changing good parts.

Short version some how he installed a 6 volt battery and just never picked up on the fact.