Pinpoint Test D: DTCs B1A61:11 and 15
Climate Control System
Pinpoint Test D: DTCs B1A61:11 and 15
Normal Operation
The in-vehicle 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 HVAC 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 HVAC 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 temperature sensor
- HVAC module
PINPOINT TEST D : DTCs B1A61:11 AND 15
D1 CHECK THE IN-VEHICLE TEMPERATURE SENSOR RESISTANCE
- Ignition OFF.
- Disconnect: In-Vehicle Temperature Sensor C233.
- Carry out the In-Vehicle Temperature Sensor component test. Climate Control System
Does the in-vehicle temperature sensor test OK?
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 HVAC MODULE OUTPUT VOLTAGE
- Ignition ON.
- Measure the voltage between in-vehicle temperature sensor C233-2, circuit VH414 (GN/BU), harness side and C233-1, circuit RH111 (GY/BU), harness side.
Is the voltage between 4.7 and 5.1 volts?
Yes
INSTALL a new in-vehicle temperature sensor. CLEAR the DTCs. REPEAT the self-test. If the DTC returns, GO to D7.
No
For DTC B1A61:11, GO to D5.
For DTC B1A61:15, GO to D3.
D3 CHECK THE IN-VEHICLE TEMPERATURE SENSOR FEEDBACK CIRCUIT FOR AN OPEN
- Ignition OFF.
- Disconnect: HVAC Module- Dual Automatic Temperature Control (DATC) C228A.
- Disconnect: HVAC Module- DATC (Dual Automatic Temperature Control) C228B.
- Measure the resistance between HVAC module- DATC (Dual Automatic Temperature Control) C228B-29, circuit VH414 (GN/BU), harness side and in-vehicle temperature sensor C233-2, circuit VH414 (GN/BU), harness side.
Is the resistance less than 5 ohms?
Yes
GO to D4.
No
REPAIR circuit VH414 (GN/BU) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
D4 CHECK THE SIGNAL RETURN CIRCUIT FOR AN OPEN
- Measure the resistance between HVAC module- DATC (Dual Automatic Temperature Control) C228A-23, circuit RH111 (GY/BU), harness side and in-vehicle temperature sensor C233-1, circuit RH111 (GY/BU), harness side.
Is the resistance less than 5 ohms?
Yes
GO to D7.
No
REPAIR circuit RH111 (GY/BU) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
D5 CHECK THE IN-VEHICLE TEMPERATURE SENSOR FEEDBACK CIRCUIT FOR A SHORT TO THE SIGNAL RETURN CIRCUIT
- Ignition OFF.
- Disconnect: HVAC Module- DATC (Dual Automatic Temperature Control) C228A.
- Disconnect: HVAC Module- DATC (Dual Automatic Temperature Control) C228B.
- Measure the resistance between in-vehicle temperature sensor C233-2, circuit VH414 (GN/BU), harness side and C233-1, circuit RH111 (GY/BU), harness side.
Is the resistance greater than 10,000 ohms?
Yes
GO to D6.
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.
D6 CHECK THE IN-VEHICLE TEMPERATURE SENSOR FEEDBACK CIRCUIT FOR A SHORT TO GROUND
- Measure the resistance between HVAC module- DATC (Dual Automatic Temperature Control) C228B-29, circuit VH414 (GN/BU), harness side and ground.
Is the resistance greater than 10,000 ohms?
Yes
GO to D7.
No
REPAIR circuit VH414 (GN/BU) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
D7 CHECK THE HVAC MODULE CONNECTION
- Inspect the HVAC module component and harness side connectors for:
- corrosion
- damaged pins
- pushed-out terminals
- Connect and correctly seat all the HVAC module connectors.
- Clear the DTCs.
- Enter the following diagnostic mode on the scan tool: Self-Test- HVAC Module.
- 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. TEST the system for normal operation.