Code No.B1045: Motor drive system for the front air mix damper

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

PROBABLE CAUSES

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

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III actuator test
Check that the following actuator test can be executed normally. (Refer to .)

  • Item 10: F.Air mix dumper motor: 0%
  • Item 11: F.Air mix dumper motor: 50%
  • Item 12: F.Air mix dumper motor: 100%

Q. Is the check result normal?
Go to Step 5.
Go to Step 2.

STEP 2. Connector check: C-105 A/C-ECU connector and C-11 front air mixing damper control motor and potentiometer connector






Q. Is the check result normal?

Go to Step 3.

Repair the connector.

STEP 3. Check the wiring harness between C-105 A/C-ECU connector (terminals 31 and 32) and C-11 front air mixing damper control motor and potentiometer connector (terminals 1 and 2).







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

Q. Is the check result normal?

Go to Step 4.

Repair the wiring harness.

STEP 4. Check the front air mixing damper control motor and potentiometer.
Refer to .

Q. Is the check result normal?
Go to Step 5.
Replace the air mixing damper control motor and potentiometer.

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

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