DTC No. P1B03-11 Fail Safe Relay Hardwire Lo side stiction diagnosis

DTC SET CONDITION

Check Condition

During the BMU termination (1 minute after the IGCT power supply is turned OFF)

Judgment Criterion

A few seconds after the main relay is turned OFF from ON status.

TROUBLESHOOTING HINTS

Damaged wiring harness and connectors
Malfunction of the PHEV-ECU
Malfunction of the BMU

DIAGNOSIS

Required Special Tools:

MB992744: Vehicle communication interface-Lite (V.C.I.-Lite)
MB992745: V.C.I.-Lite main harness A
MB992747: V.C.I.-Lite USB cable short
MB992748: V.C.I.-Lite USB cable long
MB991223: Wiring harness set
MB992006: Extra fine probe

1.Voltage measurement at drive battery connector (control wiring harness connector) (Main contactor forcible shut-off signal line)

(1) Disconnect the connector, and measure at the wiring harness side.

(2) Measure the voltage of the following.

Voltage between the drive battery connector (control wiring harness connector) (terminal No. 32) and body ground

OK: Battery voltage

Is the check result normal?

2.Check of main contactor forcible shut-off signal line between PHEV-ECU connector and drive battery connector (control wiring harness connector)

Check the following for short to ground circuit.

Short to ground circuit between the PHEV-ECU connector (CSDN terminal) and drive battery connector (control wiring harness connector) (terminal No. 32)

Is the check result normal?

Repair the connector(s) or wiring harness.

3.Check whether the DTC is set again.

(1) Erase the DTC set in the BMU2.

(2) Erase the DTC set in the BMU.

(3) Change the power supply mode of the electric motor switch to ON (READY indicator: ON).

(4) Wait for 10 seconds or more.

(5) Change the power supply mode of the electric motor switch to OFF.

(6) Wait for 10 seconds or more.

(7) Change the power supply mode of the electric motor switch to ON (READY indicator: OFF).

(8) Check whether the DTC is set again.

Is the DTC set?

Replace the PHEV-ECU (Refer to PHEV-ECU REMOVAL AND INSTALLATION

The trouble can be an intermittent malfunction (Refer to General Information - How to Use Troubleshooting/Inspection Service Points, How to Cope with Intermittent Malfunctions HOW TO COPE WITH INTERMITTENT MALFUNCTIONS

4.Check of data list

(1) Disconnect the drive battery connector (control wiring harness connector).

(2) Check the following PHEV-ECU data list item.

item No. 610: Main Contactor Compulsion cutoff signal

OK: ON

Is the check result normal?

Replace the PHEV-ECU (Refer to PHEV-ECU REMOVAL AND INSTALLATION

5.Check whether the DTC is set again.

(1) Erase the DTC set in the BMU2.

(2) Erase the DTC set in the BMU.

(3) Change the power supply mode of the electric motor switch to ON (READY indicator: ON).

(4) Wait for 10 seconds or more.

(5) Change the power supply mode of the electric motor switch to OFF.

(6) Wait for 10 seconds or more.

(7) Change the power supply mode of the electric motor switch to ON (READY indicator: OFF).

(8) Check whether the DTC is set again.

Is the DTC set?

6.Drive battery control wiring harness check (Main contactor forcible shut-off signal line)

(1) Disassemble the drive battery (Refer to SERVICE PROCEDURE

(2) Check the following wiring harness for short to ground circuit.

Between the BMU connector (terminal No. 16) and the drive battery connector (control wiring harness connector) (terminal No. 32)

Is the check result normal?

Replace the BMU (Refer to BATTERY MANAGEMENT UNIT (BMU) REMOVAL AND INSTALLATION

Repair the connector(s) or wiring harness.