Starter Solenoid Disgnosis

Starter Solenoid Disgnosis

>I finally had an opportunity to get under my car with a meter; the starter
>is constantly running whenever the battery is hooked up.
>I checked all the posts on the solenoid and found something that confuses
>there seem to be two smaller gauge "hot" wires running to the solenoid. I
>would assume one is constant hot and the other is triggered hot when the key
>is in the start position.

There should be three wires hooked to the solenoid.

Large battery cable. This hooked directly to battery positive.

Medium-sized red wire hooked to the same post. This is the feed wire from the alternator that charges the battery

Smaller yellow wire, hooked to a different post. This is the wire from the starter relay that supplies power to trigger the starter solenoid. This should have voltage only when the start relay is energized, which should happen only when the ignition switch is in the start position and the auto trans is in neutral or park.

Start relay stuck in the activated position.
Starter solenoid stuck in the start position.
Ignition switch stuck in the start position.
A short to 12 vdc in the yellow wire from the start relay to the start solenoid.

To test:

Pull the starter relay out of the central power panel. Check terminal 86 in the relay socket for 12 vdc - if there is 12 vdc, the ignition switch is stuck.

If there is no voltage on terminal 86 of the socket, check for continuity between terminals 30 and 87 on the relay (not the socket). If there is continuity, the relay is stuck.

If there is no continuity between terminals 30 and 87 of the relay, then get the car in a condition where it is safe for the starter to operate. Disconnect the yellow wire from the start solenoid. Reconnect the battery. If the starter operates, the start solenoid is stuck.

If nothing happens when you connect the battery, then touch the yellow wire to its terminal on the solenoid. If the starter operates, the yellow wire is shorted to 12 vdc.

Wally Plumley
928 Specialists

928 Tips Home     Greg's Home