Component Inspection

Air Conditioner

B1237 Ambient temperature sensor short (Low) - Component Inspection

Component Inspection

Check ambient sensor
1. Ignition "OFF"
2. A/C-ECU, ambient sensor : Connect.
3. Measure resistance between Signal (+) terminal of ambient sensor harness connector and Sensor ground terminal of ambient sensor harness connector. (Component side)
A. Specification : Refer the specifications in fig.1








FIG.1) ** Resistance value of ambient temp. sensor as a function of temperature.
4. Is "resistance" display near the specified value?
YES
1) Go to "Check A/C-ECU" procedure.
NO
1) Substitute with a known-good ambient sensor and check for proper operation. If the problem is corrected, replace ambient sensor and then go to "Verification of Vehicle Repair" procedure.
Check A/C-ECU
1. Ignition "OFF"
2. A/C-ECU : Connect, ambient sensor : Disconnect.
3. Ignition "ON"(ENGINE "OFF").
4. Measure voltage between Signal (+) terminal of ambient sensor harness connector and and chassis ground. (Component side)
A. Specification : Approx. 5 V




5. Is "voltage" display near the specified value?
YES
1) Check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and then go to "Verification of Vehicle Repair" procedure.
NO
1) Substitute with a known-good A/C-ECU and check for proper operation. If the problem is corrected, replace A/C-ECU and then go to "Verification of Vehicle Repair" procedure.