Code No. B1016, B1017: Heater water temperature sensor system










COMMENTS ON TROUBLE SYMPTOM
This code is set when the heater water temperature sensor circuit is short (Code No.B1016) or is open (Code No.B1017).

PROBABLE CAUSES

  • Malfunction of the heater water temperature sensor
  • Damaged the wiring harness or connectors
  • Malfunction of the automatic A/C control panel (A/C-ECU)

DIAGNOSIS PROCEDURE

STEP 1. Connector check: D-08 A/C-ECU connector and D-112 heater water temperature sensor connector

Q. Is the check result normal?
Go to Step 2.
Repair the connector.

STEP 2. Check the wiring harness between D-08 A/C-ECU connector (terminals 8 and 25) and D-112 heater water temperature sensor connector (terminals 1 and 2).

  • Check the sensor signal line and earth line for open or short circuit.

Q. Is the check result normal?
Go to Step 3.
Repair the wiring harness.

STEP 3. Check the heater water temperature sensor.
Refer to .

Q. Is the check result normal?
Go to Step 4.
Replace the heater water temperature sensor.

STEP 4. M.U.T.-III diagnosis code

Q. Is the diagnosis code set?
Replace the automatic A/C control panel (A/C-ECU).
The trouble can be an intermittent malfunction (Refer to GROUP 00, How to Cope with Intermittent Malfunction ).