Starting System: Other Chevrolet TrailBlazer I

Intermittents

Intermittent faulty electrical connections or wiring may be the cause of intermittent conditions. Check for loose, bent or corroded terminals and terminal tension. Check for cut, bare or pinched wiring. Simulate the condition that is potentially causing the intermittent connection, either by wiggling the connections or the wiring, test driving or performing other operations while observing scan tool, DVOM or other testing equipment.

STARTER SOLENOID DOES NOT CLICK

1. Did you perform the DIAGNOSTIC SYSTEM CHECK - ENGINE ELECTRICAL? If so, go to next step. If not, go to «DIAGNOSTIC SYSTEM CHECK - ENGINE ELECTRICAL»(ref-168810-S30498099262004111800000) .
2. Turn the ignition switch to the START position. Does the engine crank? If so, go to «INTERMITTENTS»(ref-168810-S39646039712004111800000) . If not, go to next step.
3. Is the security indicator flashing? If so, go to DIAGNOSTIC STARTING POINT - THEFT DETERRENT in DOOR LOCKS & ANTI-THEFT SYSTEM article in ACCESSORIES & EQUIPMENT. If not, go to next step.
4. Install a scan tool. Turn ON the ignition, with the engine OFF. With a scan tool, observe the CRANK parameter in the PCM data list. Turn the ignition switch to the START position. Does the scan tool display YES? If so, go to next step. If not, go to step 13 .
5. Turn ON the ignition, with the engine OFF. With a scan tool, observe the STARTER RELAY COMMAND parameter in the PCM data list. Turn the ignition switch to the START position. Does the scan tool display YES? If so, go to step 7 . If not, go to next step.
6. Turn ON the ignition, with the engine OFF. Verify that the transmission is in Park or Neutral. With a scan tool, observe the CURRENT GEAR parameter in the PCM data list. Does the scan tool display PARK or NEUTRAL? If so, go to next step. If not, go to RANGE SELECTOR DISPLAYS INCORRECT RANGE in DIAGNOSIS article in AUTOMATIC TRANSMISSION in TRANSAXLE/TRANSMISSION.
7. Turn the ignition switch to the START position. Do you hear the Starter relay click? If so, go to step 10 . If not, go to next step.
8. Turn OFF the ignition. Disconnect the Starter relay. Turn ON the ignition, with the engine OFF. Connect a test light between the battery positive voltage circuit of the Starter relay coil and a good ground. Does the test light illuminate? If so, go to next step. If not, go to step 21 .
9. Connect a test light between the battery positive voltage circuit of the Starter relay coil and the control circuit of the Starter relay. Turn the ignition to the START position. Does the test light illuminate? If so, go to step 17 . If not, go to step 15 .
10. Turn OFF the ignition. Disconnect the Starter relay. Connect a test light between the battery positive voltage circuit of the Starter relay switch and a good ground. Does the test light illuminate? If so, go to next step. If not, go to step 22 .
11. Connect a 30 amp fused jumper between the battery positive voltage circuit of the Starter relay switch and the Starter solenoid crank voltage circuit. Does the engine crank? If so, go to step 17 . If not, go to next step.
12. Does the fuse in the jumper open? If so, go to step 23 . If not, go to step 14 .
13. Turn OFF the ignition. Disconnect the PCM harness connector. Connect a test light between the crank voltage circuit of the PCM and a good ground. Turn the ignition to the START position. Does the test light illuminate? If so, go to step 20 . If not, go to step 16 .
14. Test the Starter solenoid crank voltage circuit for a high resistance or open. Did you find and correct the condition? If so, go to step 28 . If not, go to step 18 .
15. Test the control circuit of the Starter relay for an open or short to battery voltage. Did you find and correct the condition? If so, go to step 28 . If not, go to step 20 .
16. Test the crank voltage circuit of the PCM for a high resistance or open. Did you find and correct the condition? If so, go to step 28 . If not, go to step 19 .
17. Inspect for poor connections at the Starter relay. Did you find and correct the condition? If so, go to step 28 . If not, go to step 24 .
18. Inspect for poor connections at the Starter solenoid. Did you find and correct the condition? If so, go to step 28 . If not, go to step 25 .
19. Inspect for poor connections at the ignition switch. Did you find and correct the condition? If so, go to step 28 . If not, go to step 26 .
20. Inspect for poor connections at the harness connector of the PCM. Did you find and correct the condition? If so, go to step 28 . If not, go to step 27 .
21. Repair an open or high resistance in the battery positive voltage circuit of the Starter relay coil. After repair is complete, go to step 28 .
22. Repair the open or high resistance in the battery positive voltage circuit of the Starter relay switch. After repair is complete, go to step 28 .
23. Repair the short to ground in the Starter solenoid crank voltage circuit. After repair is complete, go to step 28 .
24. Replace the Starter relay. After replacement is complete, go to step 28 .
25. Replace the Starter Motor. See «STARTER MOTOR»(ref-168810-S35649805742004111800000) under REPLACEMENT PROCEDURES. After replacement is complete, go to step 28 .
26. Replace the ignition switch. See IGNITION SWITCH under REMOVAL & INSTALLATION in appropriate IGNITION SWITCH/STEERING LOCK article in ACCESSORIES & EQUIPMENT. After replacement is complete, go to step 28 .
27. Replace the PCM. See POWERTRAIN CONTROL MODULE in REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE. After replacement is complete, go to next step.
28. Operate the system for which the symptom occurred. Did you correct the condition? If so, then system is okay. If not, go to step 2 .

STARTER SOLENOID CLICKS, ENGINE DOES NOT CRANK

1. Did you perform the DIAGNOSTIC SYSTEM CHECK - ENGINE ELECTRICAL? If so, go to next step. If not, go to «DIAGNOSTIC SYSTEM CHECK - ENGINE ELECTRICAL»(ref-168810-S30498099262004111800000) .
2. Turn the ignition to the START position. Did the starter solenoid click? If so, go to next step. If not, go to «STARTER SOLENOID DOES NOT CLICK»(ref-168810-S03101405442004111800000) .
3. Inspect the engine and belt drive system for mechanical binding (seized engine, seized generator). Does the engine move freely? If so, go to next step. If not, go to «ENGINE WILL NOT CRANK - CRANKSHAFT WILL NOT ROTATE»(ref-168810-S18717764932004111800000) .
4. Test the battery positive cable between the battery and the starter solenoid for high resistance. Did you find and correct the condition? If so, go to step 8 . If not, go to next step.
5. Test the ground circuit between the battery and the starter motor for a high resistance. Did you find and correct the condition? If so, go to step 8 . If not, go to next step.
6. Inspect for poor connections at the starter motor. Did you find and correct the condition? If so, go to step 8 . If not, go to next step.
7. Replace the Starter Motor. See «STARTER MOTOR»(ref-168810-S35649805742004111800000) under REPLACEMENT PROCEDURES. After replacement, go to next step.
8. Operate the system in order to verify the repair. Did you correct the condition? If so, then system is okay. If not, go to step 2 .

ENGINE CRANKS SLOWLY

Inspect the following items

1. Perform the Battery Inspection/Test. See «BATTERY TESTING & INSPECTION 2003»(ref-167411-S17001628002004101300000) in GENERATORS & REGULATORS article in ELECTRICAL.
2. Inspect the wiring for damage. Inspect all connections to the starter motor, the solenoid, the battery, and all ground connections.
3. Verify that the engine is not seized.
4. If the battery, the wiring, and the engine are functioning properly, and the engine continues to crank slowly, replace the starter motor. See «STARTER MOTOR»(ref-168810-S35649805742004111800000) under REPLACEMENT PROCEDURES.

STARTER

The PG-260L is a non-repairable starter motor. It has pole pieces that are arranged around the armature within the starter housing. When the solenoid windings are energized, the pull-in winding circuit is completed to ground through the starter motor. The hold-in winding circuit is completed to ground through the solenoid. The windings work together magnetically to pull in and hold in the plunger. The plunger moves the shift lever. This action causes the starter drive assembly to rotate on the armature shaft spline as it engages with the flywheel ring gear on the engine. At the same time, the plunger closes the solenoid switch contacts in the starter solenoid. Full battery voltage is then applied directly to the starter motor and it cranks the engine.

As soon as the solenoid switch contacts close, current stops flowing thorough the pull-in winding as battery voltage is now applied to both ends of the windings. The hold-in winding remains energized; its magnetic field is strong enough to hold the plunger, shift lever, starter drive assembly, and solenoid switch contacts in place to continue cranking the engine. When the engine starts, the pinion gear overrun sprag protects the armature from excessive speed until the switch is opened.

When the ignition switch is released from the CRANK position, voltage is removed from the starter solenoid S terminal. Current flows from the motor contacts through both windings to ground at the end of the hold-in winding. However, the direction of the current flow through the pull-in winding is now in the opposite direction of the current flow when the winding was first energized. The magnetic fields of the pull-in and hold-in windings now oppose one another. This action of the windings, along with the help of the return spring, cause the starter drive assembly to disengage and the solenoid switch contacts to open simultaneously. As soon as the contacts open, the starter motor is turned off.