DTC P0A1B-1F: Generator Control Module Circuit Intermittent: Notes

1. - 

Detecting condition: 

Reset malfunction from power supply IC inside Inverter with converter assembly

Motor generator control ECU power supply IC resets and outputs DTC when internal power supply voltage error under microcomputer normal operation voltage or microcomputer malfunction occurs.

(1 trip detection logic)

Trouble symptom: 

Hybrid system stopped

Wiring diagram: 

Hybrid system Ref. to WIRING SYSTEM (CROSSTREK MODEL (HEV))>HYBRID ELECTRIC VEHICLE SYSTEM>WIRING DIAGRAM .

Courtesy of SUBARU OF AMERICA, INC.

Courtesy of SUBARU OF AMERICA, INC.

1. CHECK DTC  .

   Read the following DTCs using Subaru Select Monitor. Ref. to P-HEV HYBRID POWERTRAIN CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) . Ref. to P-HEV DRIVE MOTOR (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

   • P-HEV Hybrid Powertrain Control
   • P-HEV Drive Motor
   NOTE:

   Malfunction contents	System	Related DTC
   Communication system malfunction	P-HEV Drive Motor	P312487	LOST COMMUNICATION BETWEEN DRIVE MOTOR "A" AND HV ECU MISSING MESSAGE
   	P-HEV Hybrid Powertrain Control	P312387	LOST COMMUNICATION WITH DRIVE MOTOR CONTROL MODULE "A" FROM HYBRID/EV CONTROL MODULE MISSING MESSAGE
   		U011087	LOST COMMUNICATION WITH DRIVE MOTOR CONTROL MODULE MISSING MESSAGE

   When "Only DTC P0A1B1F is displayed", go to  A.

   When DTCs related to [P-HEV Hybrid Powertrain Control] mentioned above are simultaneously displayed, go to  B.

   When DTCs related to [P-HEV Drive Motor] mentioned above are simultaneously displayed, go to  C.

   Yes: 

   1. Go to  2.
   2. Perform the diagnosis for the simultaneously displayed DTCs.
   3. Perform the diagnosis for the simultaneously displayed DTCs.

   No:  -

2. CHECK THE CONNECTING CONDITION OF CONNECTOR (Inverter with converter assembly LOW PRESSURE CONNECTOR)  .
   CAUTION: Make sure to wear insulated gloves and protective goggles during the work.
   1. Check that the Service plug is disconnected. Ref. to HYBRID ELECTRIC VEHICLE>SERVICE PLUG .
   2. Check the connecting condition of low pressure connectors (HV23) and (HV24) in Inverter with converter assembly and check the relevant terminals for contact pressure, deformation and intrusion of water or foreign matter. Ref. to HYBRID ELECTRIC VEHICLE>INVERTER AND CONVERTER ASSEMBLY .
   NOTE: When connecting the connector, insert to the end with the lock lever raised, then fold the lock lever completely until a click is heard. After connected, make sure that the lock claw does not loosen and pull the connector to see that it does not come off.

   Is there looseness at the connector connection, or any poor contact, deformation or intrusion of water or foreign matters at the relevant terminals?

   Yes:  Connect the connector securely. Or repair the poor contact of connector.

   No:  Go to  3.

3. CHECK Wire harness AND CONNECTOR (Inverter with converter assembly - IGCT IG relay)  .
   CAUTION: Make sure to wear insulated gloves and protective goggles during the work.
   1. Disconnect Inverter with converter assembly connector (HV23).
   2. Remove the IGCT IG relay from the Relay holder. Ref. to WIRING SYSTEM (CROSSTREK MODEL (HEV))>FUSE AND RELAY .
   3. Using a tester, measure the resistance between Relay holder and Inverter with converter assembly connector, and between Inverter with converter assembly connector and chassis ground.

   Connector & terminal 

   (HV23) No. 1 - (B225) No. 33:

   (HV23) No. 5 - (B225) No. 33:

   (HV23) No. 4 - Chassis ground:

   (HV23) No. 8 - Chassis ground:

   Is the resistance less than 1 Ω?

   Yes:  Replace Inverter with converter assembly. Ref. to HYBRID ELECTRIC VEHICLE>INVERTER AND CONVERTER ASSEMBLY .

   No:  Repair or replace Wire harness between Inverter with converter assembly connector and Relay holder or between Inverter with converter assembly connector and chassis ground.