B1A61:15
Climate Control System
Pinpoint Test D: DTCs B1A61:11 and B1A61:15
Refer to Wiring Diagram Set 55, Automatic Climate Control System for schematic and connector information [1][2]Diagrams By Number.
Normal Operation
Under normal operation, the in-vehicle air temperature sensor receives a ground from the HVAC module. The sensor varies its resistance with the temperature. As the temperature rises, the resistance falls. As the temperature falls the resistance rises. The HVAC module measures this resistance to determine the temperature at the sensor.
- DTC B1A61:11 (Cabin Temperature Sensor: Circuit Short to Ground)- The module senses lower than expected voltage on the sensor feedback circuit, indicating a short to ground.
- DTC B1A61:15 (Cabin Temperature Sensor: Circuit Short to Battery or Open)- The module senses greater than expected voltage on the sensor feedback circuit, indicating a short to voltage or an open circuit or sensor.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- In-vehicle air temperature sensor
- HVAC module
PINPOINT TEST D : DTCs B1A61:11 AND B1A61:15
D1 CHECK THE SENSOR RESISTANCE
- Ignition OFF.
- Disconnect: In-Vehicle Temperature Sensor C233.
- Measure the resistance between the in-vehicle temperature sensor C233 terminals and compare to the table below.
Ambient Temperature Resistance -40°C (-40°F) 869,073-1,061,986 ohms -15°C (5°F) 196,465-231,213 ohms 0°C (32°F) 89,982-102,514 ohms 15°C (59°F) 44,261-49,503 ohms 25°C (77°F) 28,500-31,500 ohms 35°C (95°F) 18,563-20,751 ohms 60°C (140°F) 6,971-8,001 ohms 85°C (185°F) 2,959-3,474 ohms
Is the resistance within the specified values for the temperatures?
Yes
GO to D2.
No
INSTALL a new in-vehicle temperature sensor. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
D2 CHECK THE SENSOR OUTPUT VOLTAGE
- Ignition ON.
- Measure the voltage between in-vehicle temperature sensor C233-1, circuit VH414 (GN/BU), harness side and C233-4, circuit RH111 (GY/BU), harness side.
Is the voltage between 4.7 and 5.1 volts?
Yes
INSTALL a new in-vehicle sensor. CLEAR the DTCs. REPEAT the self-test. If code returns, GO to D8.
No
For DTC B1A68:15, GO to D3.
For DTC B1A68:11, GO to D6.
D3 CHECK CIRCUIT VH414 (GN/BU) FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: HVAC Module C294A.
- Disconnect: HVAC Module C294B.
- Ignition ON.
- Measure the voltage between ground and HVAC module C294B-19, circuit VH414 (GN/BU), harness side.
Is any voltage present?
Yes
REPAIR circuit VH414 (GN/BU) for a short to voltage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
No
GO to D4.
D4 CHECK CIRCUIT VH414 (GN/BU) FOR AN OPEN
- Ignition OFF.
- Measure the resistance between HVAC module C294B-19, circuit VH414 (GN/BU), harness side and in-vehicle temperature sensor C233-1, circuit VH414 (GN/BU), harness side.
Is the resistance less than 5 ohms?
Yes
GO to D5.
No
REPAIR circuit VH414 (GN/BU) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
D5 CHECK CIRCUIT RH111 (GY/BU) FOR AN OPEN
- Measure the resistance between HVAC module C294A-4, circuit RH111 (GY/BU), harness side and in-vehicle temperature sensor C233-4, circuit RH111 (GY/BU), harness side.
Is the resistance less than 5 ohms?
Yes
GO to D8.
No
REPAIR circuit RH111 (GY/BU) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
D6 CHECK CIRCUIT VH414 (GN/BU) FOR A SHORT TO CIRCUIT RH111 (GY/BU)
- Ignition OFF.
- Disconnect: HVAC Module C294B.
- Measure the resistance between in-vehicle temperature sensor C233-1, circuit VH414 (GN/BU), harness side and C233-4, circuit RH111 (GY/BU), harness side.
Is the resistance greater than 10,000 ohms?
Yes
GO to D7.
No
REPAIR circuit VH414 (GN/BU) for a short to circuit RH111 (GY/BU). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
D7 CHECK CIRCUIT VH414 (GN/BU) FOR A SHORT TO GROUND
- Measure the resistance between HVAC module C294B-19, circuit VH414 (GN/BU), harness side and ground.
Is the resistance greater than 10,000 ohms?
Yes
GO to D8.
No
REPAIR circuit VH414 (GN/BU) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
D8 CHECK THE HVAC MODULE CONNECTION
- Inspect the HVAC module connectors for:
- corrosion.
- pushed-out terminals.
- damaged terminals.
- Connect and correctly seat all the HVAC module connectors.
- Clear the DTCs.
- Operate the system and verify the concern is still present.
Is the concern still present?
Yes
INSTALL a new HVAC module. TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.