DTC P1C30: Lost Communication With Drive Motor Inverter: Wiring Diagram

WARNING: This page is about a different car, the 2015 Subaru XV Crosstrek. However, it is still accessible from the selected car via links, so may be relevant.

Hybrid system < Ref. to WIRING DIAGRAM , Hybrid Electric Vehicle System.>

Fig 1: Drive Motor A Inverter Power Supply Circuit - Wiring Diagram

Courtesy of SUBARU OF AMERICA, INC.

DTC PROCEDURE

Step	Check	Yes	No
1 CHECK CURRENT DATA. Using the Subaru Select Monitor, perform «Drive Motor Inverter power supply relay» of System Operation Check Mode for the drive motor control system. < Ref. to DRIVE MOTOR CONTROL SYSTEM , OPERATION, System Operation Check Mode.> Confirm the current data of in System Operation Check Mode, the value of «Drive Motor Inverter Operation Update Counter».	Does «Drive Motor Inverter Operation Update Counter» stop when «Drive Motor Inverter power supply relay» is OFF?	Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again. NOTE: In this case, temporary poor contact of connector, temporary open or short circuit of harness may be the cause.	Go to step 2 .
2 CHECK RELAY. Check the inverter power supply relay as a single unit. < Ref. to RELAY AND FUSE .>	Is the condition normal? (Check for continuity between terminals, damage, etc.)	Go to step 3 .	Replace the relay.
3 CHECK HARNESS (SHORT TO GROUND). Turn the ignition to OFF. Disconnect the ground cable of the 12 volt auxiliary battery, and as for the 12 volt engine restart battery, disconnect the ground cable from the 12V engine restart battery sensor. < Ref. to BATTERY , NOTE, Note.> Remove the service disconnect plug. < Ref. to SERVICE PLUG .> Wait for 10 minutes. Disconnect the drive motor inverter connector. Disconnect the DMCM connector. Using a tester, measure the resistance between the drive motor inverter connector and the ground bolt of inverter frame body. Connector & terminal (R432) No. 2 - Ground bolt of inverter frame body: (R432) No. 7 - Ground bolt of inverter frame body:	Is the resistance 1 MΩ or more?	Go to step 4 .	Repair short circuit to ground in harness between drive motor inverter connector and DMCM connector, or repair the intermediate connector.
4 CHECK HARNESS (OPEN CIRCUIT). Using a tester, measure the resistance between drive motor inverter connector and DMCM connector and between the ground bolt of inverter frame body and inverter power supply relay. Connector & terminal: (R442) No. 22 - (R432) No. 2: (R440) No. 11 - (R432) No. 7: (R432) No. 12 - Ground bolt of inverter frame body:	Is the resistance less than 1 Ω?	Go to step 5 .	Repair open circuit in harness between drive motor inverter connector and DMCM connector or between drive motor inverter connector and inverter power supply relay, or repair the intermediate connector.
5 CHECK HARNESS (SHORT TO POWER AND SHORT TO OTHER SIGNAL LINES). Disconnect the intermediate connector (R436). Using a tester, measure the resistance within DMCM connector, between DMCM connector and intermediate connector (R436), and within drive motor inverter connector. Connector & terminal: (R442) No. 22 - (R442) No. 1 - 22: (R442) No. 22 - (R443) No. 1 - 26: (R442) No. 22 - (R436) No. 1 - 8: (R442) No. 22 - (R432) No. 7:	Is the resistance 1 MΩ or more?	Go to step 6 .	Repair short circuit in harness between drive motor inverter connector and DMCM connector or repair the intermediate connector.
6 CHECK DRIVE MOTOR INVERTER. Replace the drive motor inverter. < Ref. to INVERTER .> Perform the Inspection Mode. < Ref. to INSPECTION MODE .>	Is the same DTC detected? (current malfunction)	Replace DMCM. < Ref. to appropriate DRIVE MOTOR CONTROL MODULE in Continuously Variable Transmission TH58A article.>	Problem is present in drive motor inverter.