Ambient Air Temperature Sensor, Checking
Special tools and workshop equipment required
- Multimeter.
- Wiring diagram.
Test procedure
-- Perform a preliminary check to verify the customers complaint. Refer to PRELIMINARY CHECK .
Start diagnosis
-- Connect the scan tool.
-- Engine MUST be at room temperature.
-- Switch the ignition ON.
-- Using the scan tool, check the ambient air temperature:
| Diagnostic text | Specified value |
|---|---|
| Ambient Air Temperature (AAT) | Approx. ambient air temperature |
If the specified value was obtained:
-- Fault may be intermittent. Check for proper connection, damaged wiring or loose terminals.
-- Go to Final procedures.
The reading will default to 419° F if the circuit is open or shorted to ground.
If the specified value was Not obtained:
-- Connect a Multimeter to terminals 1 and 2 of the Ambient Air Temperature Sensor - G17- electrical harness connector.
-- Switch the ignition ON.
Specified value: About 5.0 V.
-- Switch the ignition OFF.
If the specified value was obtained:
Replace the Ambient Air Temperature Sensor - G17-. Refer to the appropriate Service Information.
-- Go to Final procedures.
If the specified value was Not obtained:
-- Remove the Vehicle electrical system control module -J519-. Refer to the appropriate Service Information.
-- Disconnect the Vehicle electrical system control module -J519- electrical harness connector T32a.
-- Using a Multimeter, check the Ambient Air Temperature Sensor -G17- electrical harness connector to the Vehicle electrical system control module -J519- electrical harness connector T32a for an open circuit or a short, refer to the appropriate wiring diagram.
| Ambient Air Temperature Sensor -G17- electrical harness connector terminals: | Vehicle electrical system control module -J519- electrical connector T32a terminals: |
|---|---|
| 1 | 25 |
| 2 | 10 |
Specified value: 1.5 Ω max.
If the specified values were Not obtained:
-- Check the wiring connection for an open circuit.
-- Check the wiring connection for damage, corrosion, loose or broken terminals.
-- If necessary, repair the faulty wiring connection.
-- Go to Final procedures.
If the specified value was obtained:
-- Replace the Vehicle electrical system control module -J519-. Refer to the appropriate Service Information.
Final procedures
After the repair work, the following work steps must be performed in the following sequence:
- Check the DTC memory. Refer to DIAGNOSTIC MODE 03 - READ DTC MEMORY .
- If necessary, erase the DTC memory. Refer to DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
- If the DTC memory was erased, generate readiness code. Refer to READINESS CODE .