Ignition issue.

[smothers12]

I have a 1985 Silverado where a mouse must have chewed through the main electrical wire that goes from the battery to the starter. Without knowing this, I tried to start the truck, it turned over a couple times, then a burnt electrical smell and smoke was coming from under the hood.

I replaced the wire and the starter. Now I have all electronics restored but when I turn the key, nothing happens. The lights don't dim and it doesn't even click. If I arc the solenoid on the starter, it turns over and runs just fine.

I have checked all the fuses and relays under the dash. Those don't appear burnt out and I've tried swapping relays and that doesn't work either.

Is there anything else that could have shorted out?
Are there other fuses or relays that I'm missing?
Or is there something with the ignition that could be causing it?

[j cAT]

since when you bypass the solenoid it cranks over then check you feed wire to the solenoid. when key to crank position see if its 12volts.

the starter motor always has 12volts to it at all times. when you put key to crank the feed to the solenoid is then applied to energize the solenoid. this high current switch then applies the constant battery feed to the motor.

when you tried to start it it smoked so the wire to the solenoid the small one is what burned up. now this may have damaged the ignition switch. not sure with 85 but you could also have a relay that switches the ignition switch signal to the solenoid.usually called crank fuse or crank relay .. good luck .

[smothers12]

When I turn the key to the on or crank position, it doesn't change from 12V. It stays constant. It acts like nothing happens. It doesn't click, lights don't dim, nothing.

I checked all the fuses and relays under the dash and everything is fine there.

Could it be anything other than the ignition switch?

[j cAT]

Originally Posted by smothers12

When I turn the key to the on or crank position, it doesn't change from 12V. It stays constant. It acts like nothing happens. It doesn't click, lights don't dim, nothing.

I checked all the fuses and relays under the dash and everything is fine there.

Could it be anything other than the ignition switch?

what wire you talk about ? battery feed BIG FAT wire , or the small wire ?

small wire should have 12 volts when key in crank mode only............

BIG FAT wire is always 12 volts...

[smothers12]

The big wire constantly has 12V but the small wire has 0V in the off, on, and crank position.

[Blue Bowtie]

Are the fusible links intact? There are probably several at the starter main power node or at the battery end of that cable.

[j cAT]

Originally Posted by smothers12

The big wire constantly has 12V but the small wire has 0V in the off, on, and crank position.

follow that small wire from the solenoid back and find out where its damaged/chewed up etc.. that small wire may have a fuse in it or the starter relay . not sure on a 92 ... on vehicles I have worked the ignition switch in crank causes a relay to energize. the relay contacts then apply power the starter solenoid , to cause the heavy 12 volt wire to power the starter motor. you jump the 12 volts to this small wire then the engine cranks which is what you stated earlier.. so see where its broken.

[smothers12]

Now I'm really confused. I jumped in the truck yesterday, turned the key, and it started no problem. Drove it around and parked it.

Today, I turned the key and it is back to the original problem. No turning over, no clicking, nothing.

Ideas?

[j cAT]

Originally Posted by smothers12

Now I'm really confused. I jumped in the truck yesterday, turned the key, and it started no problem. Drove it around and parked it.

Today, I turned the key and it is back to the original problem. No turning over, no clicking, nothing.

Ideas?

being this old the ignition switch could be bad in the crank position. remove the switch at the base of the steering column see how it looks/wiring connectors look..
The shift lever has a switch to prevent cranking in gear. move the selector to neutral and see if it cranks . find this switch see if you get 12volts on it when in crank position on both connections in neutral/park ..