Toyota wiring question

[Black Bear]

I am eliminating my ingition switch b/c the key wont stay in at all. The wiring diagram fom Haynes has only 4 wires into the switch, 12 in, starter, ACC, ignition. But there are five wires on the back of the switch. What is the 5th one to?




I did some testing with a jumper wire, but nothing noticeable happened when 12v was applied to the unknown wire. Any help would be great.

 

[jeepn-jason]

ck it with a test light. I would say it is probably a second constant 12v. Most ign switches have 2 sources of 12v.

 

[Black Bear]

Did that, its not 12v in.

 

[RatLabGuy]

I'd think it would be easier to just tack weld the key into the ignition...?

 

[Black Bear]

maybe, but I have a small switch panel that I would like to use and go keyless.

 

[jeepn-jason]

What color is the wire, ill see if some of my diagrams show it.

 

[Black Bear]

Its black with no stripe.

it has ST2 molded into the plastic right by where it solders into the switch. The Starter wire has ST1 by it.. so two starter wires?

 

[orangesonoma]

test the wire as you turn the key and see if it lights up at all

 

[rattlecanpaint]

ground?

 

[snappy]

Some cars do have a second starter wire. What year is the truck and I'll check Mitchell.

 

[snappy]

On a 85 pickup mitchell says it's for a cold start injector.

 

[Black Bear]

its an 81.

I dont think its a ground.

 

[orangesonoma]

did you test the wire as you cycle the key...that will tell you what it is for...

 

[Black Bear]

I did and I got about .8v didnt seem right.

 

[Tetanus]

John - It's your backfire igniter wire.

 

[Black Bear]

I disconnected the battery, and I measured the resistance across the 12v IN, and the mystery wire, and the resistance fluctuated between 90 ohms, and 140 ohms in the start position. No continuity on any other position. Its a starter wire, but wtf for?

 

[Black Bear]

I cut the wire, and it started right up. so its getting disconnected.