Pinpoint Test E: DTCs B1379:11 and 15
Climate Control System
Pinpoint Test E: DTCs B1379:11 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 auxiliary 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 B1379:11 (Rear 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 B1379:15 (Rear 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
- Auxiliary in-vehicle air temperature sensor
- HVAC module
PINPOINT TEST E: DTCs B1379:11 AND 15
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E1 CHECK THE SENSOR RESISTANCE
- Ignition OFF.
- Disconnect: Auxiliary In-Vehicle Temperature Sensor C3366.
- Measure the resistance between auxiliary in-vehicle temperature sensor C3366 terminals and compare to the table below.
- Is the resistance within the specified values for the temperatures?
Yes
GO to E2.
No
INSTALL a new auxiliary in-vehicle temperature sensor. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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E2 CHECK THE SENSOR OUTPUT VOLTAGE
- Ignition ON.
- Measure the voltage between auxiliary in-vehicle temperature sensor C3366-1, circuit VH414 (GN/BU), harness side and C3366-2, circuit RH111 (GY/BU), harness side.
- Is the voltage between 4.7 and 5.1 volts?
Yes
INSTALL a new auxiliary in-vehicle sensor. CLEAR the DTCs. REPEAT the self-test. If the DTC returns, GO to E8.
No
For DTC B1379:15, GO to E3.
For DTC B1379:11, GO to E6.
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E3 CHECK CIRCUIT VH414 (GN/BU) FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: HVAC Module C2356A.
- Disconnect: HVAC Module C2356B.
- Ignition ON.
- Measure the voltage between ground and HVAC module C2356B-25, 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 E4.
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E4 CHECK CIRCUIT VH414 (GN/BU) FOR AN OPEN
- Ignition OFF.
- Measure the resistance between HVAC module C2356B-25, circuit VH414 (GN/BU), harness side and auxiliary in-vehicle temperature sensor C3366-1, circuit VH414 (GN/BU), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to E5.
No
REPAIR circuit VH414 (GN/BU) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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E5 CHECK CIRCUIT RH111 (GY/BU) FOR AN OPEN
- Measure the resistance between HVAC module C2356A-4, circuit RH111 (GY/BU), harness side and auxiliary in-vehicle temperature sensor C3366-2, circuit RH111 (GY/BU), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to E8.
No
REPAIR circuit RH111 (GY/BU) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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E6 CHECK CIRCUIT VH414 (GN/BU) FOR A SHORT TO CIRCUIT RH111 (GY/BU)
- Ignition OFF.
- Disconnect: HVAC Module C2356B.
- Measure the resistance between auxiliary in-vehicle temperature sensor C3366-1, circuit VH414 (GN/BU), harness side and C3366-4, circuit RH111 (GY/BU), harness side.
- Is the resistance greater than 10,000 ohms?
Yes
GO to E7.
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.
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E7 CHECK CIRCUIT VH414 (GN/BU) FOR A SHORT TO GROUND
- Measure the resistance between HVAC module C2356B-25, circuit VH414 (GN/BU), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to E8.
No
REPAIR circuit VH414 (GN/BU) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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E8 CHECK THE HVAC 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. REFER to Climate Control Heating Ventilation Air Conditioning (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.
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