Code No. U1175: Electrical parking lock LIN Slave not responding



caution Whenever ECU is replaced, ensure that the CAN bus lines are normal.

TROUBLE JUDGEMENT


The PHEV-ECU stores diagnosis code No. U1175 when it cannot communicate with the electrical parking lock driver unit via LIN correctly.

PROBABLE CAUSES



  • Malfunction of LIN bus
  • Malfunction of electrical parking driver unit
  • Malfunction of PHEV-ECU
  • Noise interruption in LIN bus wires

DIAGNOSIS PROCEDURE


STEP 1. Resistance measurement at the electrical parking driver unit.


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the resistance between E01, E02 terminal and body earth.
OK: Continuity exists (2 Ω or less)

Q. Is the check result normal?

Go to Step 3.
Go to Step 2.

STEP 2. Check the earth line for open circuit (electrical parking driver unit and the body earth).



  • Check the wiring harness between electrical parking driver unit (E01, E02 terminals) connector and body earth.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction ).
Repair the connector or wiring harness.

STEP 3. Voltage measurement at electrical parking driver unit.


(1)Disconnect the connector, and measure at the wiring harness side.
(2)Measure the voltage between the electrical parking driver unit connector (BATT terminal) and body earth.
OK: System voltage

Q. Is the check result normal?

Go to Step 5.
Go to Step 4.

STEP 4. Check the power supply line for open and short circuit. (ETACS-ECU and the electrical parking driver unit).



  • Check the wiring harness between ETACS-ECU (BUP3 and BUP4 terminal) connector and the electrical parking driver unit (BATT terminal) connector.

Q. Is the check result normal?

The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction ).
Repair the connector or wiring harness.

STEP 5. Check the power supply line for open and short circuit. (PHEV-ECU and the electrical parking driver unit).



  • Check the wiring harness between PHEV-ECU (LIN1 terminal) connector and the electrical parking driver unit (LIN terminal) connector.

Q. Is the check result normal?

Go to Step 6.
Repair the connector or wiring harness.

STEP 6. Check whether the diagnosis code is stored again.


Recheck if the diagnosis code is stored.
(1)Erase the diagnosis code.
(2)Turn on the power supply mode of the electric motor switch.
(3)Check if the diagnosis code is stored.

Q. Is the diagnosis code stored?

Replace the PHEV-ECU (Refer to ).
A poor connection, open circuit or other intermittent malfunction in the LIN bus line between the PHEV-ECU and the parking lock driver unit.(Refer to GROUP 00, How to Cope with Intermittent Malfunction ).