Code No. U1920: K-line error (master lost)




PROBABLE CAUSES




DIAGNOSIS PROCEDURE


STEP 1. Check the wiring harness wires and connectors between the PHEV-ECU connector and the power drive unit connector.



Q. Is the check result normal?

Go to Step 2.

Repair a fault.

STEP 2. Measure the voltage at the power drive unit connector.


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Turn on the power supply mode of the electric motor switch.
(3)Measure the voltage between the power drive unit connector (KLN1) and body earth.
OK: Approximately 5V

Q. Is the check result normal?

Go to Step 3.

Go to Step 4.

STEP 3. Check whether the diagnosis code is stored again.


Check again if the FEMCU stores diagnosis code No. U1920.
(1)Erase the stored diagnosis code.
(2)Power supply mode of electric motor switch: OFF
(3)Power supply mode of electric motor switch: ON
(4)Check if the diagnosis code is stored.

Q. Is diagnosis code stored?

Replace the power drive unit. (Refer to .) Then go to Step 5.

Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/How to Cope with Intermittent Malfunctions ).

STEP 4. Check whether the diagnosis code is stored again.


Check again if the FEMCU stores diagnosis code No. U1920.
(1)Erase the stored diagnosis code.
(2)Power supply mode of electric motor switch: OFF
(3)Power supply mode of electric motor switch: ON
(4)Check if the diagnosis code is stored.

Q. Is diagnosis code stored?

Replace the PHEV-ECU. (Refer to .) Then go to Step 5.

Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/How to Cope with Intermittent Malfunctions ).

STEP 5. Check whether the diagnosis code is stored again.


Check whether the FEMCU stores a diagnosis code again.
(1)Erase the stored diagnosis code.
(2)Power supply mode of electric motor switch: OFF
(3)Power supply mode of electric motor switch: ON
(4)Check if the diagnosis code is stored.

Q. Is diagnosis code stored?

Return to Step 1.

This diagnosis is complete.