Charging System Diagnosis Chevrolet/Oldsmobile

1. Check the hydrometer eye that is built into the vehicle Battery before troubleshooting the Charging System.

•	Green eye -- Battery is charged.

•	Dark eye -- Battery is discharged. Recharge Battery.

•	Clear or yellow eye -- Battery fluid is low. Replace Battery.

2. Check the Generator belt.
3. Check that the Generator connector terminals are clean and tight.
4. Check that the Battery connections are clean and tight.
5. Check Fuse 39. If open, check CKT 39 for a short to ground.

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Check for a broken (or partially broken) wire inside of the insulation which could cause system malfunction but prove "GOOD" in a continuity/voltage check with a system disconnected. These circuits may be intermittent or resistive when loaded, and if possible, should be checked by monitoring for a volage drop with the system operational (under load).

•	Check for proper installation of the aftermarket electronic equipment which may affect the integrity of other systems (refer to "Troubleshooting Procedures," page 8A-4-0).

•	Refer to "System Diagnosis" in this section.

1. Check the hydrometer eye that is built into the vehicle Battery before troubleshooting the Starter System.

•	Green eye -- Battery is charged.

•	Dark eye -- Battery is discharged. Recharge Battery.

•	Clear or yellow eye -- Battery fluid is low. Replace Battery.

2. Check that the Starter Solenoid terminals "S" and "B" are clean and tight.
3. Check that all Battery grounds are clean and tight.
4. Check Fuse 11 Fuse. If open check CKTS 806 and 575 for a short to ground.

•

Check for a broken (or partially broken) wire inside of the insulation which could cause system malfunction but prove "GOOD" in a continuity/voltage check with a system disconnected. These circuits may be intermittent or resistive when loaded, and if possible, should be checked by monitoring for a voltage drop with the system operational (under load).

•	Check for proper installation of aftermarket electronic equipment which may affect the integrity of other systems (refer to "Troubleshooting Procedures," page 8A-4-0).

•	Refer to "System Diagnosis" in this section.

Important: If the Starter and Charging System continues to malfunction after the following diagnostic procedures are performed, refer to ENGINE CONTROLS.

Charging System Diagnosis Pontiac

1. Check the hydrometer eye that is built into the vehicle Battery before troubleshooting the Starter System.

•	Green eye -- Battery is charged.

•	Dark eye -- Battery is discharged. Recharge battery.

•	Clear or yellow eye -- Battery fluid is low. Replace battery.

2. Check that the Starter Solenoid terminas "S" and "B" are clean and tight.
3. Check that all the Battery grounds are clean and tight.
4. Check IGN MAIN 1 MaxiFuse. If open, check CKTS 42, 5, and 6 for a short to ground.

•

Check for a broken (or partially broken) wire inside of the insulation which could cause system malfunction but prove "GOOD" in a continuity/voltage check with a system disconnected. These circuits may be intermittent or resistive when loaded, and if possible, should be checked by monitoring for a voltage drop with the system operational (under load).

•	Check for proper installation of aftermarket electronic equipment which may affect the integrity of other systems (refer to "Troubleshooting Procedures," page 8A-4-0).

•	Refer to "System Diagnosis" in this section.

1. Check the hydrometer eye that is built into the vehicle Battery before troubleshooting the Charging System.

•	Green eye -- Battery is charged.

•	Dark eye -- Battery is discharged. Recharge battery.

•	Clear or yellow eye -- Battery fluid is low. Replace Battery.

2. Check the Generator belt.
3. Check that the Generator connector terminals are clean and tight.
4. Check that Battery connections are clean and tight.
5. Check I/P IGN Fuse. If open, check ckt 39 for a short to ground.
6. Check ALT SENSE Fuse. If open, check ckt 2740 for a short to ground.

•

Check for a broken (or partially broken) wire inside of the insulation which could cause system malfunction but prove "GOOD" in a continuity/voltage check with a system disconnected. These circuits may be intermittent or resistive when loaded, and if possible, should be checked by monitoring for a volage drop with the system operational (under load).

•	Check for proper installation of the aftermarket electronic equipment which may affect the integrity of other systems (refer to "Troubleshooting Procedures," page 8A-4-0).

•	Refer to "System Diagnosis" in this section.

Important: If the Starter and Charging System continues to malfunction after the following diagnostic procedures are performed, refer to ENGINE CONTROLS.

Charging System Diagnosis Buick

1. Check the hydrometer eye that is built into the vehicle battery before troubleshooting the starter system.

•	Green eye -- Battery is charged.

•	Dark eye -- Battery is discharged.

•	Clear or yellow eye -- Battery fluid is low. Replace battery.

2. Check that the starter solenoid terminals S and B and battery connections are clean and tight.
3. Check that all battery grounds are clean and tight.
4. Check IGN MAIN 1 MaxiFuse. If open,, check circuit 42 for a short to ground.
5. Check CRANK MaxiFuse. If open, check circuit 6 for a short to ground.
6. Check CRANK SIGNAL fuse. If open, check circuit 806 for a short to ground.
7. Check PCM-BCM fuse. If open, check circuit 439 for a short to ground.

•

Check for a broken (or partially broken) wire inside of the insulation which could cause system malfunction but prove GOOD in a continuity/voltage check with a system disconnected. These circuits may be intermittent or resistive when loaded, and if possible, should be checked by monitoring for a voltage drop with the system operational (under load).

•	Check for proper installation of aftermarket electronic equipment which may affect the integrity of other systems. Refer to Troubleshooting Procedures, page 8A-4-0.

•	Refer to System Diagnosis in this section.

1. Check the hydrometer eye that is built into the vehicle battery before troubleshooting the charging system.

•	Green eye -- Battery is charged.

•	Dark eye -- Battery is discharged. Recharge battery.

•	Clear or yellow eye -- Battery fluid is low. Replace battery.

2. Check the generator belt.
3. Check that the generator connector terminals are clean and tight.
4. Check that battery connections are clean and tight.
5. Check I/P IGN Fuse. If open, check circuit 39 for a short to ground.
6. Check GEN fuse. If open, check circuit 2740 for a short to ground.

•

Check for a broken (or partially broken) wire inside of the insulation which could cause system malfunction but prove GOOD in a continuity/voltage check with a system disconnected. These circuits may be intermittent or resistive when loaded, and if possible, should be checked by monitoring for a volage drop with the system operational (under load).

•	Check for proper installation of the aftermarket electronic equipment which may affect the integrity of other systems. Refer to Troubleshooting Procedures, page 8A-4-0.

•	Refer to System Diagnosis in this section.

Important: If the Starter and Charging System continues to malfunction after the following diagnostic procedures are performed, refer to Engine Controls.