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Pinpoint Test C: DTC C1B14:11 or C1B14:12




Climate Control System

Pinpoint Tests

Pinpoint Test C: DTC C1B14:11 or C1B14:12

Refer to Wiring Diagram Set 54, Manual Climate Control System for schematic and connector information. Diagrams By Number

Refer to Wiring Diagram Set 55, Automatic Climate Control System for schematic and connector information. Diagrams By Number

Normal Operation

A 5-volt reference voltage is supplied to the sensors and actuators from the HVAC module.

- DTC C1B14:11 (Sensor Supply Voltage A: Circuit Short to Ground) - sets when the HVAC module senses less than 3 volts on the sensor reference voltage circuit, indicating a short directly to ground.
- DTC C1B14:12 (Sensor Supply Voltage A: Circuit Short to Battery) - sets when the HVAC module senses greater than 5.7 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 C1B14:11 OR C1B14:12

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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 C5.

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C2 CHECK THE REFERENCE VOLTAGE CIRCUIT FOR A SHORT TO GROUND

- Ignition OFF.
- Disconnect: HVAC Module - Electronic Manual Temperature Control (EMTC) C294A.
- Disconnect: HVAC Module - Dual Automatic Temperature Control (DATC) C228A/C2109A.
- Disconnect: HVAC Module - DATC C228B/C2109B.

For vehicles without navigation




- For vehicles without navigation, measure the resistance between ground and HVAC module - EMTC C294A-24 or HVAC module - DATC C2109A-24, circuit LH111 (BN/WH), harness side.

For vehicles with navigation




- For vehicles with navigation, measure the resistance between ground and HVAC module - DATC C228A-11, circuit LH111 (BN/WH), harness side.
- Is the resistance greater than 10,000 ohms?

Yes
GO to C3.

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 THE REFERENCE VOLTAGE CIRCUIT AND THE SIGNAL RETURN CIRCUIT FOR A SHORT TOGETHER

For vehicles without navigation




- For vehicles without navigation, measure the resistance between HVAC module - EMTC C294A-24 or HVAC module - DATC C2109A-24, circuit LH111 (BN/WH), harness side and HVAC module - EMTC C294A-23 or HVAC module - DATC C2109A-23, circuit RH111 (GY/BU), harness side.

For vehicles with navigation




- For vehicles with navigation, measure the resistance between HVAC module - DATC C228A-11, circuit LH111 (BN/WH), harness side and HVAC module C228A-10, circuit RH111 (GY/BU), harness side.
- Is the resistance greater than 200 ohms?

Yes
GO to C6.

No
GO to C4.

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C4 CHECK THE ACTUATORS

For vehicles without navigation




- For vehicles without navigation, measure the resistance between HVAC module - EMTC C294A-24 or HVAC module - DATC C2109A-24, circuit LH111 (BN/WH), harness side and HVAC module - EMTC C294A-23 or HVAC module - DATC C2109A-23, circuit RH111 (GY/BU), harness side.

For vehicles with navigation




- For vehicles with navigation, measure the resistance between HVAC module - DATC C228A-11, circuit LH111 (BN/WH), harness side and HVAC module C228A-10, circuit RH111 (GY/BU), harness side.
- While measuring the resistance, disconnect the following components one at a time, in order. Stop disconnecting components if the measured resistance rises above 200 ohms.
- In-vehicle temperature and humidity sensor C2247
- Air inlet mode door actuator C289
- Defrost/panel/floor mode door actuator C236
- Temperature blend door actuator C2381 ( EMTC only)
- LH temperature blend door actuator C2091 ( DATC only)
- RH temperature blend door actuator C2092 ( DATC only)
- Did the resistance rise above 200 ohms?

Yes
INSTALL a new actuator or sensor (the last one to be disconnected). When installing an actuator, CONNECT the actuator electrical connector before the HVAC module connector(s). This allows the actuator to be calibrated when the HVAC module is reconnected. TEST the system for normal operation.

No
REPAIR circuits LH111 (BN/WH) and RH111 (GY/BU) for a short together. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.

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C5 CHECK THE REFERENCE VOLTAGE CIRCUIT FOR A SHORT TO VOLTAGE

- Ignition OFF.
- Disconnect: HVAC Module - EMTC C294A.
- Disconnect: HVAC Module - DATC C228A/C2109A.
- Disconnect: HVAC Module - DATC C228B/C2109B.

For vehicles without navigation




- For vehicles without navigation, measure the voltage between ground and HVAC module - EMTC C294A-24 or HVAC module - DATC C2109A-24, circuit LH111 (BN/WH), harness side.

For vehicles with navigation




- For vehicles with navigation, measure the voltage between ground and HVAC module - DATC C228A-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 C6.

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C6 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.
- 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. REFER to Climate Control Service and Repair. 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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