Dtc 13 Evaporator Temperature Sensor Circuit
DESCRIPTION
WIRING DIAGRAM
INSPECTION PROCEDURE
CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY (TE VOLTAGE)
INSPECT NO. 1 COOLER THERMISTOR (A/C THERMISTOR)
CHECK HARNESS AND CONNECTOR (NO. 1 COOLER THERMISTOR - AIR CONDITIONING AMPLIFIER)
DTC 13 Evaporator Temperature Sensor Circuit |
DESCRIPTION
The No. 1 cooler thermistor (A/C thermistor) is installed on the evaporator in the A/C unit. It detects the temperature of the cooled air that has passed through the evaporator which is then used in air conditioning control. The resistance of the No. 1 cooler thermistor (A/C thermistor) changes in accordance with the temperature of the cooled air that has passed through the evaporator. As the temperature decreases, the resistance increases. As the temperature increases, the resistance decreases.The air conditioning amplifier applies voltage (5 V) to the No. 1 cooler thermistor and reads voltage changes as the resistance of the No. 1 cooler thermistor changes. This thermistor is used for frost prevention.DTC Code
| Detection Item
| Trouble Area
|
13
| Open or short in evaporator temperature sensor circuit
| - No. 1 cooler thermistor (A/C thermistor)
- Harness or connector
- Air conditioning amplifier assembly
|
WIRING DIAGRAM
INSPECTION PROCEDURE
1.CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY (TE VOLTAGE) |
Remove the air conditioning amplifier with its connectors still connected.
Measure the voltage according to the value(s) in the table below.
- Standard Voltage:
Tester Connection
| Switch Condition
| Specified Condition
|
A15-1 (TE) - A15-14 (SG-4)
| Ignition switch ON Evaporator temperature: 0°C (32°F)
| 2.0 to 2.4 V
|
Ignition switch ON Evaporator temperature: 15°C (59°F)
| 1.4 to 1.8 V
|
- HINT:
- As the temperature increases, the voltage decreases.
ResultResult
| Proceed to
|
OK (Checking from the PROBLEM SYMPTOMS TABLE)
| A
|
OK (Checking from the DTC)
| B
|
NG
| C
|
2.INSPECT NO. 1 COOLER THERMISTOR (A/C THERMISTOR) |
Remove the thermistor.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection
| Condition
| Specified Condition
|
1 - 2
| -10°C (14°F)
| 7.30 to 9.10 kΩ
|
-5°C (23°F)
| 5.65 to 6.95 kΩ
|
0°C (32°F)
| 4.40 to 5.35 kΩ
|
5°C (41°F)
| 3.40 to 4.15 kΩ
|
10°C (50°F)
| 2.70 to 3.25 kΩ
|
15°C (59°F)
| 2.14 to 2.58 kΩ
|
20°C (68°F)
| 1.71 to 2.05 kΩ
|
25°C (77°F)
| 1.38 to 1.64 kΩ
|
30°C (86°F)
| 1.11 to 1.32 kΩ
|
- NOTICE:
- Even slightly touching the thermistor may change the resistance value. Be sure to hold the connector of the thermistor.
- When measuring the resistance, the thermistor temperature must be the same as the ambient temperature.
- HINT:
- As the temperature increases, the resistance decreases (Refer to the graph).
| REPLACE NO. 1 COOLER THERMISTOR (A/C THERMISTOR) |
|
|
3.CHECK HARNESS AND CONNECTOR (NO. 1 COOLER THERMISTOR - AIR CONDITIONING AMPLIFIER) |
Disconnect the A19 thermistor connector.
Disconnect the A15 amplifier connector.
Measure the resistance according to the value(s) in the table below.
- Standard Resistance:
Tester Connection
| Condition
| Specified Condition
|
A15-1 (TE) - A19-1
| Always
| Below 1 Ω
|
A15-14 (SG-4) - A19-2
|
A15-1 (TE) - Body ground
| Always
| 10 kΩ or higher
|
A15-14 (SG-4) - Body ground
|
| REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
|