Starting System: Testing and Inspection

NOTE: The air temperature must be between 59 and 100° F (15 and 38° C) before testing.

Recommended Procedure:
- Use a starter system tester.
- Connect and operate the equipment in accordance with the manufacturer's instructions.
- Test and troubleshoot as described.

Alternate Procedure:
- Use the following equipment:
- Ammeter, 0 - 400 A
- Voltmeter, 0 - 20 V (accurate within 0.1 volt)
- Tachometer, 0 - 1,200 rpm




- Hook up voltmeter and ammeter as shown.

NOTE: After this test, or any subsequent repair, reset the ECM/PCM to clear any codes (see Fuel and Emission system).

Check Starter Engagement
1. Remove No. 33 (20 A) fuse from the under-hood fuse/relay box.
2. Turn the ignition switch to START (III) with the shift lever in [N] or [P] position (A/T) or with the clutch pedal depressed (M/T). The starter should crank the engine.
- If the starter does not crank the engine, go to step 3.
- If it cranks the engine erratically or too slowly, go to "Check for Wear and Damage".
3. Check the battery, battery positive cable, ground, starter cut relay, and the wire connections for looseness and corrosion. Test again. If the starter still does not crank the engine, go to step 4.
4. Unplug the connector (BLK/WHT wire and solenoid terminal) from the starter.




5. Connect a jumper wire from the battery positive (+) terminal to the solenoid terminal. The starter should crank the engine.
- If the starter still does not crank the engine, remove it, and diagnose its internal problem.
- If the starter cranks the engine, go to step 6.
6. Check the ignition switch.
7. Check the starter cut relay.
8. Check the A/T gear position switch (A/T) or clutch interlock switch (M/T).
9. Check for an open in the WHT/RED wire between the ignition switch and starter cut relay, and check for an open in the BLK/WHT wire between the starter cut relay and starter.

Check for Wear and Damage
The starter should crank the engine smoothly and steadily. If the starter engages, but cranks the engine erratically, remove it, and inspect the starter drive gear and torque converter ring gear or flywheel ring gear for damage.

Check the drive gear overrunning clutch for binding or slipping when the armature is rotated with the drive gear held. If damaged, replace the gears.

Check Cranking Voltage and Current Draw
Cranking voltage should be no less than 8.5 Volts.
Current draw should be no more than 350 amperes.

If cranking voltage is too low, or current draw too high, check for:
- Dead or low battery
- Open circuit in starter armature commutator segments
- Starter armature dragging
- Shorted armature winding
- Excessive drag in engine

Check Cranking rpm
Engine speed during cranking should be above 100 rpm.
If speed is too low, check for:
- Loose battery or starter terminals
- Excessively worn starter brushes
- Open circuit in commutator segments
- Dirty or damaged helical spline or drive gear
- Defective drive gear overrunning clutch

Check Starter Disengagement
With the shift lever in [P] or [N] (A/T) or with the clutch pedal depressed (M/T), turn the ignition switch to "III", and release to "II". The starter drive gear should disengage from the torque converter ring gear when you release the key.

If the drive gear hangs up on the torque converter ring gear, check for:
- Solenoid plunger and switch malfunction
- Dirty drive gear assembly or damaged overrunning clutch

Starter Solenoid Test
1. Check the hold-in coil for continuity between the S terminal and the armature housing (ground). The coil is OK if there is continuity.




M/T:




A/T:




2. Check the pull-in coil for continuity between the S and M terminals. The coil is OK if there is continuity.

Armature Inspection and Test




1. Inspect the armature for wear or damage due to contact with the permanent magnet. If there is wear or damage, replace the armature.
2. Check commutator surface and diameter.




- If the surface is dirty or burnt, resurface with emery cloth or a lathe within the following specifications, or recondition with #500 or #600 sandpaper.
- If commutator diameter is below the service limit, replace the armature.




Commutator Diameter

3. Measure the commutator runout.
- If the commutator runout is within the service limit, check the commutator for carbon dust or brass chips between the segments.
- If the commutator runout is not within the service limit, replace the armature.




Commutator Runout

4. Check the mica depth. If necessary, undercut the mica with a hacksaw blade to achieve proper depth. If the service limit cannot be maintained, replace the armature.




Commutator Mica depth




5. Check for continuity between the segments of the commutator. If an open circuit exists between any segments, replace the armature.




6. Place the armature on an armature tester. Hold a hacksaw blade on the armature core.
If the blade is attracted to the core or vibrates while the core is turned, the armature is shorted. Replace the armature.




7. Check with an ohmmeter that no continuity exists between the commutator and armature coil core, and between the commutator and armature shaft. If continuity exists, replace the armature.

Starter Brush Holder Test

1. Check that there is no continuity between the (+) and (-) brush holders.
If there is continuity, replace the brush holder assembly.




M/T:




A/T:




2. Insert the brush into the brush holder, and bring the brush into contact with the commutator, then attach a spring scale to the spring. Measure the spring tension at the moment the spring lifts off the brush.




Spring Tension

Starter Brush Inspection

Measure the brush length.
If it is not within the service limit, replace the armature housing assembly (M/T), or the brush holder assembly (A/T).




Brush Length

NOTE: To seat new brushes after installing them in their holders, slip a Strip of #500 or #600 sandpaper, with the grit side up, over the commutator, and smoothly rotate the armature. The contact surface of the brushes will be sanded to the same contour as the commutator.

Solenoid Plunger Inspection (M/T)




Check the contact points and the face of the starter solenoid plunger for burning, pitting or any other defects. If surfaces are rough, recondition them with a strip of #500 or #600 sandpaper.

Starter Field Winding Test (M/T)




1. Check for continuity between the brushes. If there is no continuity, replace the armature housing.
2. Check for continuity between each brush and the armature housing (ground).
If there is continuity, replace the armature housing.

Overrunning Clutch Inspection
1. Slide the overrunning clutch along the shaft.
Does it move freely? If not, replace it.




2. Rotate the overrunning clutch both ways.
Does it lock in one direction and rotate smoothly in reverse? If it does not lock in either direction or it locks in both directions, replace it.
3. If the starter drive gear is worn or damaged, replace the overrunning clutch assembly; the gear is not available separately.
4. Check the condition of the flywheel or torque converter ring gear if the starter drive gear teeth are damaged.