Inspection Procedure 10: The outlet air temperature can not be changed even if the amount of solar radiation changes




CIRCUIT OPERATION


When the blower air temperature can not be changed even if the amount of solar radiation is changed, the photo sensor may be defective.

PROBABLE CAUSES

  • Malfunction of photo sensor
  • Damaged harness wires and connectors
  • Malfunction of the A/C-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code.
Check whether the A/C sets a diagnosis code or not.

Q. Is the check result normal?
Go to Step 2.
Refer to diagnosis code chart .

STEP 2. M.U.T.-III data list.
Check that the following data list display contents are normal. (Refer to .)

  • Item 67: Photo sensor

Q. Is the check result normal?
Go to Step 3.
Go to Step 4.

STEP 3. Recheck the trouble symptom

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

STEP 4. Connector check: C-41 photo sensor connector and C-44 A/C-ECU connector




Q. Is the check result normal?

Go to Step 5.

Repair the connector.

STEP 5. Check the wiring harness between C-41 photo sensor connector (terminal 1 and 2) and C-44 A/C-ECU connector (terminal 41 and 38).




note Prior to the wiring harness inspection, check joint connector C-137 and C-138, and repair if necessary.

  • Check the A/C-ECU input line for open circuit.

Q. Is the check result normal?

Go to Step 6.

Repair the wiring harness. Check that the A/C works normally.

STEP 6. Replace the photo sensor and recheck the trouble symptom
Check that the A/C works normally.

Q. Is the check result normal?
This diagnosis is complete.
Replace the automatic A/C control panel (A/C-ECU).