Code No.B1055 Motor drive system for rear air mix damper <vehicles with dual automatic A/C>














COMMENTS ON TROUBLE SYMPTOM
This code is set when the rear air mixing damper cannot be rotated to the preset opening angle.

PROBABLE CAUSES

  • Malfunction of the rear air mixing damper control motor and potentiometer
  • Malfunction of the automatic A/C control panel (A/C-ECU)
  • Damaged the wiring harness or connectors

DIAGNOSIS PROCEDURE

STEP 1. Connector check: D-07 A/C-ECU connector and E-134-1 rear air mixing damper control motor and potentiometer connector

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

STEP 2. Check the wiring harness between D-07 A/C-ECU connector (terminals 51 and 52) and E-134-1 rear air mixing damper control motor and potentiometer connector (terminals 2 and 1).
note Prior to the wiring harness inspection, check intermediate connector D-219 and D-133 and rear heater unit connector E-134, and repair if necessary.

  • Check the motor activating lines for open or short circuit.

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

STEP 3. Check the rear air mixing damper control motor and potentiometer.
Refer to .

Q. Is the check result normal?
Go to Step 4.
Replace the air mixing damper control motor and potentiometer.

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 ).