
FULL-AUTOMATIC AIR CONDITIONER –
Troubleshooting
55-36
Code No.15 Heater water temperature sensor system
(open circuit)
Probable cause
This diagnosis code is output if the power supply line or input line of the heater
water temperature sensor is open-circuited and no heater water temperature sensor
signals are input to A/C-ECU.
D
Malfunction of the heater water temperature
sensor
D
Malfunction of connector, harness
D
Malfunction of the A/C-ECU
Heater water temperature sensor check (Refer to P.55-64.)
NG
Replace
OK
Measure at the heater water temperature sensor connector B-02.
D
Disconnect the connector, and measure at the harness
side connector.
D
Voltage between terminal (1) and body earth
OK: 5 V
NG
Check the following connector:
B-04
NG
Repair
OK
Check the trouble symptom.
NG
Check the harness between the heater water temperature sensor
and the A/C-ECU.
NG
Repair
OK
Replace the A/C-ECU.
OK
Measure at the A/C-ECU connector B-04.
D
Connect the connector.
D
Voltage between terminal (4) and body earth
OK: 2.3 – 2.9 V
NG
Check the following connector:
B-02
NG
Repair
OK
Check the trouble symptom.
NG
Check the harness between the heater water temperature sensor
and the A/C-ECU, and repair if necessary.
OK
Check the following connector: B-04
NG
Repair
OK
Check the trouble symptom.
NG
Replace the A/C-ECU.
Code No.16 Heater water temperature sensor system
(short circuit)
Probable cause
This diagnosis code is output if the power supply line or output line of the heater
water temperature sensor is short-circuited and heater water temperature sensor
power supply voltage signals are input to A/C-ECU.
D
Malfunction of the heater water temperature
sensor
D
Malfunction of connector, harness
D
Malfunction of the A/C-ECU
Heater water temperature sensor check (Refer to P.55-64.)
NG
Replace
OK
Measure at the A/C-ECU connector B-04.
D
Connect the connector.
D
Voltage between terminal (4) and body earth
OK: 2.3 – 2.9 V
NG
Check the harness between the heater water temperature sensor
and the A/C-ECU, and repair if necessary.
OK
Replace the A/C-ECU.