Starting System: Testing and Inspection
Starter TestNOTE: 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.
Starter Test:
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 a voltmeter and ammeter as shown.
NOTE: After this test, or any subsequent repair, reset the PCM to clear any codes.
Check the Starter Engagement:
1. Remove the No. 44 (15 A) fuse from the under-hood fuse/relay box.
2. Turn the ignition switch to START (II) with the shift lever in [N] or [P] position. 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.
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.
Starter Test:
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.
9. Check for an open in the wire between the ignition switch 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 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 8.0 Volts. Current draw should be no more than 200 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 splines or drive gear.
- defective drive gear overrunning clutch.
Check Starter Disengagement
With the shift lever in [N] or [P] position, turn the ignition switch to START (II), and release to ON (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
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.
2. Check the pull-in coil for continuity between the S and M terminals. The coil is OK if there is continuity.
Field Winding Test
Field Winding Test:
1. Check for continuity between the brushes. If there's 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.
Brush Inspection
Measure the brush length. If it is not within the service limit, replace the brush (or brush holder assembly).
Brush Inspection:
Brush Length
Standard (New): 14.0 - 14.5 mm (0.55- 0.57 in)
Service Limit: 9.0 mm (0.35 in)
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.
Overrunning Clutch Inspection
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 torque converter ring gear if the starter drive gear teeth are damaged.
Armature Inspection and Test
1. Inspect the armature for wear or damage due to contact with the field winding. If there is wear or damage, replace the armature.
2. Check commutator surface and diameter.
Armature Inspection And Test:
- 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.
Armature Inspection And Test:
- If commutator diameter is below the service limit, replace the armature.
Commutator Diameter
Standard (New): 27.9 - 28.0 mm (1.09 - 1.10 in)
Service Limit: 27.0 mm (1.06 in)
Armature Inspection And Test:
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
Standard (New): 0 - 0.02 mm (0 - 0.0008 in)
Service Limit: 0.05 mm (0.002 in)
Mica Depth Check:
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.
Armature Inspection And Test:
Commutator Mica Depth
Standard (New): 0.5 - 0.8 mm (0.02 - 0.03 in)
Service limit: 0.2 mm (0.008 in)
5. Check for continuity between the segments of the commutator. If an open circuit exists between any segments, replace the armature.
Armature Inspection And Test:
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.
Armature Inspection And Test:
7. With an ohmmeter, check that no continuity exists between the commutator and armature coil core, and between the commutator and armature shaft. If there is continuity, replace the armature.
Brush Holder Test
Brush Holder Test:
1. Check that there is no continuity between the (+) and (-) brush holders. If there is continuity, replace the brush holder assembly.
Checking Spring Tension:
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: 13.7 - 17.7 N
(1.40 - 1.80 Kgf, 3.09 - 4.00 lbf)