Pinpoint Test C: DTC C1B14
Climate Control System
Pinpoint Tests
Pinpoint Test C: DTC C1B14
Refer to Wiring Diagram Set 55, Automatic Climate Control System for schematic and connector information. Diagrams By Number
Normal Operation
Under normal operation, a 5-volt reference voltage is supplied to the sensors and actuators from the HVAC module through circuit LH111 (BN/WH).
- DTC C1B14:11 Sensor Supply Voltage A: Circuit Short to Ground - The module senses less than 0.1 volt on the sensor reference voltage circuit, indicating a short directly to ground.
- DTC C1B14:12 Sensor Supply Voltage A: Circuit Short to Battery - The module senses greater than 4.9 volts on the sensor reference voltage circuit, indicating a short directly to voltage.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- HVAC module
PINPOINT TEST C: DTC C1B14
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C1 CHECK THE SENSOR RESISTANCE
- Check for HVAC DTCs.
- Is DTC C1B14:11 present?
Yes
GO to C2.
No
GO to C3.
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C2 CHECK CIRCUIT LH111 (BN/WH) FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: HVAC Module C228a/C2356a.
- Disconnect: HVAC Module C228b/C2356b.
- Measure the resistance between ground and HVAC module C228a/C2356a-11, circuit LH111 (BN/WH), harness side.
- Is the resistance greater than 10,000 ohms?
Yes
GO to C4.
No
REPAIR circuit LH111 (BN/WH) for a short to ground. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
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C3 CHECK CIRCUIT LH111 (BN/WH) FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: HVAC Module C228a/C2356a.
- Disconnect: HVAC Module C228b/C2356b.
- Measure the voltage between ground and HVAC module C228a/C2356a-11, circuit LH111 (BN/WH), harness side.
- Is any voltage present?
Yes
REPAIR circuit LH111 (BN/WH) for a short to voltage. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
No
GO to C4.
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C4 CHECK THE MODULE CONNECTION
- Carry out the HVAC Module Cold Boot Process. HVAC Module Cold Boot Process
- Carry out the HVAC Module On-Demand Self Test. Alternate Diagnostic Methods - HVAC Module
- Operate the system.
- Does the concern return?
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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