Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC P1AB3: Starter/Generator Phase U Current Sensor Circuit Low VoltageDTC P1AB4: Starter/Generator Phase U Current Sensor Circuit High Voltage
DTC P1AB5: Starter/Generator Phase V Current Sensor Circuit Low Voltage
DTC P1AB6: Starter/Generator Phase V Current Sensor Circuit High Voltage
DTC P1AB7: Starter/Generator Phase W Current Sensor Circuit Low Voltage
DTC P1AB8: Starter/Generator Phase W Current Sensor Circuit High Voltage
Circuit/System Description
The starter/generator control module (SGCM) phase U/V/W current sensors are used for motor control and power inverter module (PIM) current sensor rationality check. The SGCM monitors the current sensor for the following:
| • | To detect a failure of the U/V/W-phase current sensor circuit below valid range |
| • | To detect a failure of the U/V/W-phase current sensor circuit above valid range |
If one of the above conditions is detected, the SGCM will set the appropriate DTC.
Conditions for Running the DTC
P1AB3, P1AB4, P1AB5, P1AB6, P1AB7, P1AB8
| • | Engine is running. |
| • | Wakeup signal is ON. |
Conditions for Setting the DTC
P1AB3, P1AB5, P1AB7
Sensor output voltage at high side less than 0.5 volt for 0.5 ms
P1AB4, P1AB6, P1AB8
Sensor output voltage at high side greater than 4.5 volts for 0.5 ms
Action Taken When the DTC Sets
P1AB3, P1AB4, P1AB5, P1AB6, P1AB7, P1AB8
| • | Stop PWM (MGU shutdown) |
| • | APM PWM OFF |
| • | Battery disconnection (disconnect SW on/off) |
Conditions for Clearing the DTC
P1AB3, P1AB4
U-phase current sensor circuit within valid range
P1AB5, P1AB6
V-phase current sensor circuit within valid range
P1AB7, P1AB8
W-phase current sensor circuit within valid range
Diagnostic Aids
P1AB3, P1AB5, P1AB7
Possible Electrical failure at current sensor with short to ground or open
P1AB4, P1AB6, P1AB8
Possible electrical failure at current sensor with short to voltage
Reference Information
Schematic Reference
Connector End View Reference
Hybrid Controls Connector End Views
Electrical Information Reference
Scan Tool Reference
Circuit/System Verification
Caution: To help avoid personal injury, additional precautions must be taken prior to working on the generator control module or the generator starter. After removing the 36V battery cables from the generator battery, remove both engine wiring harness connectors from the generator control module. Wait at least 5 minutes and then remove the generator control module cover. Verify voltage levels at all 36V, 12V, and 3-phase connections, are less than 3 volts using a DMM before proceeding.
- If DTC is history, refer to Testing for Intermittent Conditions and Poor Connections .
- If DTC is current, replace the SGCM.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for SGCM replacement, setup, and programming
