Code No.U1570 CAN-LIN-SWS converter (LIN bus)


caution Before replacing the ECU, ensure that the power supply circuit, the earth circuit and the communication circuit are normal.










TROUBLE JUDGMENT



COMMENTS ON TROUBLE SYMPTOM



PROBABLE CAUSES



  • Malfunction of the CAN converter-ECU
  • Malfunction of the lighting control sensor
  • LIN bus lines shorted to power supply
  • LIN bus lines shorted to earth
  • Open circuit of LIN bus line

DIAGNOSIS PROCEDURE


STEP 1. Connector check: D-252 CAN converter-ECU connector, E-136 lighting control sensor connector


Q. Is the check result normal?





STEP 2. Check the wiring harness wires between D-252 CAN converter-ECU terminal No. 12 and E-136 lighting control sensor connector terminal No. 3.



  • Check the communication lines for open circuit and short circuit.

Q. Is the check result normal?





STEP 3. Measure the voltage at the LIN bus lines.



(1)Disconnect the CAN converter-ECU connector and the lighting control sensor connector connected to the LIN bus line.
(2)Turn the ignition switch from "LOCK" (OFF) to "ON" position.
(3)Measure the voltage between E-136 lighting control sensor connector (wiring harness side) terminal No. 3 and earth.
OK: The voltmeter needle does not swing.
note If the LIN bus lines are short to power supply, the voltmeter indicates a constant value.

Q. Is the check result normal?





STEP 4. Measure the resistance at the LIN bus lines.



(1)Disconnect the CAN converter-ECU connector and the lighting control sensor connector connected to the LIN bus line.
(2)Measure the continuity between E-136 lighting control sensor connector (wiring harness side) terminal No. 3 and earth.
OK: No continuity (1 kΩ or more)

Q. Is the check result normal?





STEP 5. M.U.T.-III other system diagnosis code



Q. Is the diagnosis code set?





STEP 6. Check whether the diagnosis code is reset.



(1)Replace the lighting control sensor.
(2)Erase the diagnosis code.
(3)Turn the ignition switch from "LOCK" (OFF) position to "ON" position.
(4)Check if diagnosis code is set.

Q. Is the diagnosis code set?