Test B: DTC B1251 OR DTC B1253 - A/C In-Vehicle Temperature Sensor Open Circuit or Short to Ground
PINPOINT TEST B: DTC B1251 OR DTC B1253 - A/C IN-VEHICLE TEMPERATURE SENSOR OPEN CIRCUIT OR SHORT TO GROUNDB1:
B1-B3:
B3-B5:
B5-B6:
Normal Operation
Under normal operation, the in-vehicle air temperature sensor receives a ground from the electronic automatic temperature control (EATC) module through circuit RH104 (BN/BU). A 5-volt reference voltage is supplied to the in-vehicle air temperature sensor from the EATC module through circuit VH414 (GN/BU).
Possible Causes
- An open in circuit RH104 (BN/BU) or VH414 (GN/BU)
- A short to voltage in circuit RH104 (BN/BU)
- A short to ground in circuit VH414 (GN/BU)
- In-vehicle air temperature sensor
- EATC module