Pinpoint Test F: DTC B1947 Or B2014
Climate Control System
Pinpoint Tests
Pinpoint Test F: DTC B1947 or B2014
Refer to Wiring Diagram Set 55, Automatic Climate Control System for schematic and connector information. Diagrams By Number
Normal Operation
Under normal operation, the evaporator 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 B1947 (Climate Control A/C Post Evaporator Sensor Circuit Short To Ground) - The module senses excessive voltage drop on the sensor reference voltage circuit, indicating a short directly to ground.
- DTC B2014 (Climate Control A/C Post Evaporator Sensor Open Circuit) - The module senses no voltage drop on the sensor reference voltage circuit, indicating an open circuit.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Evaporator temperature sensor
- HVAC module - Electronic Manual Temperature Control (EMTC) or HVAC module - Dual Automatic Temperature Control (DATC)
PINPOINT TEST F: DTC B1947 OR B2014
NOTE: The evaporator temperature sensor cannot be installed independently of the heater core and evaporator core housing.
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F1 CHECK THE SENSOR RESISTANCE
- Ignition OFF.
- Disconnect: Evaporator Temperature Sensor C296.
- Carry out the Evaporator Temperature Sensor component test. Evaporator Temperature Sensor
- Is the resistance within the specified values for the temperatures?
Yes
GO to F2.
No
INSTALL a new heater core and evaporator core housing. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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F2 CHECK THE HVAC MODULE SENSOR OUTPUT VOLTAGE
- Ignition ON.
- Press the AUTO button.
- Measure the voltage between evaporator temperature sensor C296-2, circuit (LG/BK), harness side and C296-1, circuit (BK), harness side.
- Is the voltage between 4.7 and 5.1 volts?
Yes
GO to F7.
No
For DTC B2826, GO to F3.
For DTC B2827, GO to F5.
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F3 CHECK CIRCUIT VH406 (VT/BN)/(LG/BK) FOR AN OPEN
- Ignition OFF.
- Disconnect: HVAC Module - EMTC C2357A or HVAC Module - DATC C228A.
- Measure the resistance between HVAC module - EMTC C2357A-6 or HVAC module - DATC C228A-6, circuit VH406 (VT/BN), harness side and evaporator temperature sensor C296-2, circuit (LG/BK), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to F4.
No
REPAIR circuit VH406 (VT/BN)/(LG/BK) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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F4 CHECK CIRCUIT RH111 (GY/BU)/(BK) FOR AN OPEN
- Measure the resistance between HVAC module - EMTC C2357A-10 or HVAC module - DATC C228A-10, circuit RH111 (GY/BU), harness side and evaporator temperature sensor C296-1, circuit (BK), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to F7.
No
REPAIR circuit RH111 (GY/BU)/(BK) for an open. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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F5 CHECK CIRCUIT VH406 (VT/BN)/(LG/BK) FOR A SHORT TO CIRCUIT RH111 (GY/BU)/(BK)
- Ignition OFF.
- Disconnect: HVAC Module - EMTC C2357A or HVAC Module - DATC C228A.
- Measure the resistance between evaporator temperature sensor C296-2, circuit (LG/BK), harness side and C296-1, circuit (BK), harness side.
- Is the resistance greater than 10,000 ohms?
Yes
GO to F6.
No
REPAIR circuit VH406 (VT/BN)/(LG/BK) for a short to circuit RH111 (GY/BU)/(BK). CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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F6 CHECK CIRCUIT VH406 (VT/BN)/(LG/BK) FOR A SHORT TO GROUND
- Measure the resistance between HVAC module - EMTC C2357A-6 or HVAC module - DATC C228A-6, circuit VH406 (VT/BN), harness side and ground.
- Is the resistance greater than 10,000 ohms?
Yes
GO to F7.
No
REPAIR circuit VH406 (VT/BN)/(LG/BK) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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F7 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.
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