Inspection Procedure 5: The Ambient Air Temperature is not Displayed Normal.




CIRCUIT OPERATION


RV meter displays the ambient temperature read from the ambient temperature sensor. The ambient temperature on RV meter display is calibrated in accordance with the vehicle speed state.
note When the vehicle is parked with the ignition switch at the ACC position and when the vehicle speed is 20 km/h or below with the ignition switch at the ON position, the downward calibration of displayed ambient temperature is performed, but upward calibration is not performed. With the ignition switch at the ON position, when the vehicle speed continues to be 21 km/h or higher for 30 seconds or more, the downward calibration and upward calibration of displayed ambient temperature are performed.

COMMENTS ON TROUBLE SYMPTOM


When other indications are normal, the malfunction of ambient air temperature sensor is considered.

PROBABLE CAUSES



DIAGNOSIS PROCEDURE

STEP 1. Check the following connector: A-36 ambient air temperature sensor

Q. Is the check result normal?

Go to Step 2.

Repair the defective connector.

STEP 2. Check the ambient air temperature sensor.
Check the ambient air temperature sensor.

Q. Is the check result normal?
Go to Step 3.
Replace the ambient air temperature sensor.

STEP 3. Check the communication and connection (the ambient air temperature sensor) of the service function.
Using the monitor status of the automatic mode in the service function, check the ambient temperature sensor status. (Refer to .)
Item name
 Normal condition
Amb. Temp.
 ON
OK: Normal condition is displayed.

Q. Is the check result normal?
Go to Step 6.
Go to Step 4.

STEP 4. Check the following connector: C-108 RV meter connector


Q. Is the check result normal?

Go to Step 5.

Repair the defective connector.

STEP 5. Check the harness wire between C-108 RV meter connector terminals No.3, 11 and A-36 ambient air temperature sensor connector terminals No.1, 2.



note Prior to the wiring harness inspection, check intermediate connector C-33, and repair if necessary.

  • Check the output lines for open circuit.

Q. Is the check result normal?

Go to Step 9.

Repair the wiring harness.

STEP 6. M.U.T-III other system data list
Check the vehicle speed signal data list of DIESEL system.
Item No.4: Vehicle speed sensor (Refer to GROUP 13A, Data list reference table .)

Q. Is the check result satisfactory?
Go to Step 7.
Diagnose DIESEL system (Refer to GROUP 13A , Troubleshooting ). After diagnosing the DIESEL system.

STEP 7. Check the following connector: B-01 vehicle speed sensor connector

Q. Is the check result normal?

Go to Step 8.

Repair the defective connector.

STEP 8. Check the wiring harness between B-01 vehicle speed sensor connector terminal No.3 and C-108 RV meter connector terminal No.7.




note Prior to the wiring harness inspection, check the joint connector C-127 and intermediate connector C-30, and repair if necessary.

  • Check the input line circuit.

Q. Is the check result normal?

Go to Step 9.

Repair the wiring harness.

STEP 9. Recheck for malfunction.

Q. Is a malfunction eliminated?
If no malfunctions are found in all steps, an intermittent malfunction is suspected. Refer to GROUP 00, How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction .
Replace the RV meter.