Truck won't crank

[nonickatall]

I have a problem with my truck. it won't crank.

I had that problem a month ago as well a few times and I swapped the battery, after that it didn't happen again.

Today I helped someone who had a problem with his car. His battery was empty, so I bridged his battery with my battery while my engine was running. I checked the other car for error codes and noticed that my engine was had stopped for whatever reason.

After that i tried to crank, but nothing happens.

I thought first: My battery is low and I put on a charger.

The battery is new and now full and when I turn on the ignition, I have normal lights in my instrument cluster.

When I switch to start, I have the lights going away, like normal.

But there is no crank, so I first removed my right wheel and measured at my starter, if current is available. I can measure ground to ground and I have 12 Volt at the power line, from the battery.

On the line which controls the magnetic switch of the starter, there is no 12 Volt, when I let someone start the truck.

So I looked for the starter relay. I swapped the starter relay with the equal relay next to it, with "park lp", whatever that means. No change.

So I looked for the description on the relay and I measured between 87 an 86, but there is no current, so it seems that something else don't work.

I tried to bridge 30 to 85 but the starter don't crank as well.

When I switch on the ignition. There is this sign with the lock. I'm not sure if that is always there.

Does anybody have an idea, where I can start to search for the problem?

Best regards from Germany
Ralf

 

[Scottydoggs]

the fat cable to the starter should always be 12 v hot. the small wire should show 12 v when the key is turned to crank, its the trigger wire. so if thats got power the starter is not working, if its not getting power it could be something like the starter relay, or the fuse box melted under the relay, or the ignition harness in the steering column has gone bad.

 

[Fless]

Hit this link for an electrical diagram, but you may need to change the link at the top, depending on your specific model. I suspect one of the ignition fuses may have blown, but that's just a guess.

System Diagram — 2006 Cadillac Escalade/ESV 2WD V8-6.0L VIN N Service Manual | Operation CHARM

Detailed repair manual for the 2006 Cadillac Escalade/ESV 2WD V8-6.0L VIN N.

charm.li

 

[rockola1971]

I 2nd an ignition fuse popped. After that I suspect ignition switch on the steering column is burnt at contacts.

 

[Fless]

Also, your owner's manual will have a diagram of the various electrical centers (fuseboxes) with somewhat limited descriptions of each fuse.