Pinpoint Test D: DTCs B1A61:11 and 15
Climate Control System
Pinpoint Test D: DTCs B1A61:11 and 15
Refer to Wiring Diagram Set 55, Automatic Climate Control System for schematic and connector information. 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 excessive voltage drop on the sensor feedback circuit, indicating a short directly to ground.
- DTC B1A61:15 (Cabin Temperature Sensor: Circuit Short to Battery or Open)- The module senses no voltage drop on the sensor feedback circuit, indicating a short directly to voltage or an open circuit.
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 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.
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 C233-3, circuit RH107 (GN/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 the DTC 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 C228A.
- Disconnect: HVAC Module C228B.
- Ignition ON.
- Measure the voltage between ground and HVAC module- Dual Automatic Temperature Control (DATC) C228A-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- DATC (Dual Automatic Temperature Control) C228B-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 RH107 (GN/BU) FOR AN OPEN
- Measure the resistance between HVAC module- DATC (Dual Automatic Temperature Control) C228A-4, circuit RH107 (GN/BU), harness side and in-vehicle temperature sensor C233-3, circuit RH107 (GN/BU), harness side.
Is the resistance less than 5 ohms?
Yes
GO to D8.
No
REPAIR circuit RH107 (GN/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 RH107 (GN/BU)
- Ignition OFF.
- Disconnect: HVAC Module C228B.
- Measure the resistance between in-vehicle temperature sensor C233-1, circuit VH414 (GN/BU), harness side and C233-3, circuit RH107 (GN/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 RH107 (GN/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- DATC (Dual Automatic Temperature Control) C228B-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 MODULE CONNECTION
- Inspect the 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.