P0A5B
Pinpoint Test
Pinpoint Test H: DTC P0A5A, P0A5B, P0A5C
Normal Operation
The generator current sensor is a Hall-effect sensor attached to the generator B+ cable. It is supplied a 5 volt reference and ground from the PCM. The PCM reads the generator current sensor feedback voltage to determine how much current is flowing through the generator B+ cable.
- DTC P0A5A (Generator Current Sensor Circuit Range/Performance)- The PCM does not detect current through the generator current sensor and there are no generator current sensor circuit DTCs are set.
- DTC P0A5B (Generator Current Sensor Circuit Low)- The PCM senses lower than expected voltage on the generator current sensor feedback circuit, indicating an open or a short directly to ground.
- DTC P0A5C (Generator Current Sensor Circuit High)- The PCM senses higher than expected voltage on the generator current sensor feedback circuit, indicating a short directly to voltage.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Battery current sensor
- BCM (Body Control Module)
PINPOINT TEST H : DTC P0A5A, P0A5B, P0A5C
H1 CHECK THE PCM DTCs
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: Self-Test- PCM.
- Check the PCM DTCs.
Is DTC P0A5A present?
Yes
GO to H2.
No
For DTC P0A5B, GO to H3.
For DTC P0A5C, GO to H7.
H2 CHECK THE GENERATOR CURRENT SENSOR
- Inspect the generator current sensor for the following:
- Physical damage
- Corrosion
- Disconnected electrical connector
- Disconnected from generator B+ cable
- Debris between the generator current sensor and the generator B+ cable
Are any of these conditions found during inspection?
Yes
REPAIR as necessary or INSTALL a new generator current sensor. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
No
GO to H9.
H3 CHECK THE PCM OUTPUT VOLTAGE
- Ignition OFF.
- Disconnect: Generator Current Sensor C1645.
- Ignition ON.
- Measure the voltage between ground and generator current sensor C1645-1, circuit LE424 (YE/GN), harness side.
Is the voltage between 4.7 and 5.1 volts?
Yes
GO to H4.
No
If the voltage is less than 4.7 volts, REPAIR circuit LE424 (YE/GN) for an open or high resistance. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
If the voltage is greater than 5.1 volts, REPAIR circuit LE424 (YE/GN) for a short to voltage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
H4 CHECK THE GENERATOR CURRENT SENSOR GROUND CIRCUIT
- Measure the voltage between generator current sensor C1645-2, circuit RE407 (YE/VT), harness side and generator current sensor C1645-1, circuit LE424 (YE/GN), harness side.
Is the voltage between 4.7 and 5.1 volts?
Yes
GO to H5.
No
REPAIR circuit RE407 (YE/VT) for an open or high resistance. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
H5 CHECK THE FEEDBACK CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: PCM C1551B (3.5L).
- Disconnect: PCM C175B (3.7L).
- Disconnect: PCM C1381B (5.0L).
- Measure the resistance between ground and generator current sensor C1645-3, circuit VDC61 (VT/GN), harness side.
Is the resistance greater than 10,000 ohms?
Yes
GO to H6.
No
REPAIR circuit VDC61 (VT/GN) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
H6 CHECK THE FEEDBACK CIRCUIT FOR AN OPEN
- For 3.5L engines, measure the resistance between generator current sensor C1645-3, circuit VDC61 (VT/GN), harness side and PCM C1551B-94, circuit VDC61 (VT/GN), harness side.
- Measure the resistance between generator current sensor C1645-3, circuit VDC61 (VT/GN), harness side and:
- For 3.7L engines, PCM C175B-33, circuit VDC61 (VT/GN), harness side.
- For 5.0L engines, PCM C1381B-33, circuit VDC61 (VT/GN), harness side.
Is the resistance less than 5 ohms?
Yes
GO to H7.
No
REPAIR circuit VDC61 (VT/GN) for an open or high resistance. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
H7 CHECK THE FEEDBACK CIRCUIT FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: Generator Current Sensor C1645.
- Disconnect: PCM C1551B (3.5L).
- Disconnect: PCM C175B (3.7L).
- Disconnect: PCM C1381B (5.0L).
- Ignition ON.
- Measure the voltage between ground and generator current sensor C1645-3, circuit VDC61 (VT/GN), harness side.
Is any voltage present?
Yes
REPAIR circuit VDC61 (VT/GN) for a short to voltage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
No
GO to H8.
H8 CHECK THE FEEDBACK CIRCUIT FOR A SHORT TO THE SIGNAL RETURN OR REFERENCE CIRCUIT
- Ignition OFF.
- Measure the resistance between generator current sensor C1645-3, circuit VDC61 (VT/GN), harness side and:
- generator current sensor C1645-1, circuit LE424 (YE/GN), harness side.
- generator current sensor C1645-2, circuit RE407 (YE/VT), harness side.
Is the resistance greater than 10,000 ohms?
Yes
GO to H9.
No
REPAIR circuit VDC61 (VT/GN) for a short to circuit LE424 (YE/GN) or RE407 (YE/VT). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
H9 CHECK THE GENERATOR CURRENT SENSOR CONNECTION
- Ignition OFF.
- Disconnect the generator current sensor connector.
- Inspect the generator current sensor connector for:
- corrosion
- pushed-out terminals
- damaged terminals
- Connect and correctly seat the generator current sensor connector.
- Ignition ON.
- Clear the DTCs.
- Enter the following diagnostic mode on the scan tool: Self-Test- PCM.
Did the DTC return?
Yes
REPAIR as necessary or INSTALL new generator current sensor. CLEAR the DTCs. REPEAT the self-test. If the DTC returns, GO to H10.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.
H10 CHECK FOR CORRECT PCM OPERATION
- Ignition OFF.
- Disconnect all the PCM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect the PCM connectors and make sure they seat correctly.
- Operate the system and determine if the concern is still present.
Is the concern still present?
Yes
INSTALL a new PCM. TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.