Truck won't start

[Hypoid]

When I started, battery voltage was about 12.6 volts.

Step 1: When I checked voltage in from the key switch, I had 12 volts with the key turned to crank position.



Step 2: When I checked voltage out to the starter, I had another 12 volts with the key in the crank position.



​Step 3: When I jumped the starter signal wire to the hot terminal, the voltage dropped about 1.4 volts.



If your starter does not crank like mine did in the video, you need to pull the starter and inspect the electrical connections, including where the starter bolts to the engine.

[dieseldoc]

The starters are self grounded, this can be an issue now days.
The surfaces have to be clean.
Then all the chassis grounds as well.
The new cars/trucks are so sensitive to the grounds that lose grounds can cause issues with the CPU,

[dscowell]

Alright so I tried the bypass again today with some larger wire since what I had before probably wasn't big enough. That got the starter to spin. When I tried what you did Mike I got nothing. So does that mean the ignition switch is bad? Wires?

[Patrolman]

That would mean to me that you are not getting power from the key, but you would want to check for 12v coming to the solenoid when the key is turned.

[Hypoid]

dscowell previously posted:

[dscowell]

Hypoid previously posted:

[Hypoid]

OK, measure the voltage at the stud I used in step 3, it should be the same as battery voltage. If it is not battery voltage, take the wires off and measure the voltage of the big cable. If you don't have battery voltage there, replace the cable. If you do have battery voltage there, clean everything that goes on the stud I used for step 3, including the stud.

dscowell previously posted:

[dscowell]

I tested the voltage at the stud and got 0 Volts. I replaced the larger wire and cleaned off the stud and all the wires and still got nothing.

[Hypoid]

dscowell previously posted:

[dscowell]

Yes it was the wire from the positive terminal going to the ignintion relay? Whatever part it was that has the stud with all the other wires by the battery.

[Hypoid]

Something is wrong with that picture. That stud is the distribution point for most of the electrical system.

Check for voltage at the battery cable itself, sounds like you got a bad one.

[dscowell]

So my actual battery cables or the cable going from the stub to the battery?

[Hypoid]

Stud to battery.

[dscowell]

The cable read the same as my battery

[Hypoid]

That stud should read the same.

[dscowell]

When I put my lead on the end of the stud the largest reading I got was 0.3V. When I put it on the eyelets for all the wires I get the same as my battery.

[Hypoid]

Polish the stud, nut (& washer), and wire terminations with a fine wire brush.

[dscowell]

I have not cleaned the stud and everything since I don't have wire brush yet but say that doesn't work is there anywhere else I should look? Could it even be that the whole part (starter relay?) is bad and just needs to be replaced?

[dieseldoc]

very well could be....

[Hypoid]

It looks expensive, but it is clean: ECH AR578

http://www.napaonline.com/napa/en/p/ECHAR578_0341048681