CAUTION: DO NOT engage starter solenoid for longer than 5 seconds during testing, or damage to coil winding may result.

Remove starter. Disconnect starter-to-solenoid field lead terminal. See Fig 1 . Ensure field lead does not touch starter housing. Connect negative lead of 12-volt battery to solenoid field lead terminal.
Connect another lead from negative battery terminal to starter drive housing. Connect lead from positive battery terminal to solenoid "S" terminal.
Pinion gear should extend quickly and completely when solenoid is energized. If pinion gear operates as specified, go to next step. If pinion gear does not operate as specified, replace solenoid.
Disconnect negative battery lead from solenoid field lead terminal. If pinion gear remains extended, go to next step. If pinion gear does not remain extended, replace solenoid.
Disconnect lead from starter drive housing. If pinion returns quickly to de-energized position, go to STARTER NO-LOAD TEST . If pinion does not operate as specified, repair or replace starter.

Fig 1: Testing Starter Solenoid

Courtesy of GENERAL MOTORS CORP.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Solenoid Pull-In & Hold-In Test