Pinpoint Test C: DTCs C1B14:11 and 12
Climate Control System
Pinpoint Test C: DTCs C1B14:11 and 12
Refer to Wiring Diagram Set 54, Manual Climate Control System for schematic and connector information. [1][2]Diagrams By Number
Refer to Wiring Diagram Set 55, Automatic Climate Control System for schematic and connector information. [1][2]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 : DTCs C1B14:11 AND 12
C1 CHECK THE SENSOR RESISTANCE
- Check for HVAC DTCs.
Is DTC C1B14:11 present?
Yes
GO to C2.
No
GO to C4.
C2 CHECK CIRCUIT LH111 (BN/WH) FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: HVAC Module- Electronic Manual Temperature Control (EMTC) C2357a.
- Disconnect: HVAC Module- Dual Automatic Temperature Control (DATC) C2356a.
- Disconnect: HVAC Module- DATC (Dual Automatic Temperature Control) C2356b.
- Measure the resistance between ground and HVAC module- EMTC (Electronic Manual Temperature Control) C2357A-11 or HVAC module- DATC (Dual Automatic Temperature Control) C2356A-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.
C3 CHECK CIRCUITS LH111 (BN/WH) AND RH111 (GY/BU) FOR A SHORT TOGETHER
- Measure the resistance between HVAC module- EMTC (Electronic Manual Temperature Control) C2357A-11 or HVAC module- DATC (Dual Automatic Temperature Control) C2356A-11, circuit LH111 (BN/WH), harness side and HVAC module- EMTC (Electronic Manual Temperature Control) C2357A-10 or HVAC module C2356A-10, circuit RH111 (GY/BU), harness side.
Is the resistance greater than 200 ohms?
Yes
GO to C5.
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.
C4 CHECK CIRCUIT LH111 (BN/WH) FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: HVAC Module- EMTC (Electronic Manual Temperature Control) C2357a.
- Disconnect: HVAC Module- DATC (Dual Automatic Temperature Control) C2356a.
- Disconnect: HVAC Module- DATC (Dual Automatic Temperature Control) C2356b.
- Ignition ON.
- Measure the voltage between ground and HVAC module- EMTC (Electronic Manual Temperature Control) C2357A-11 or HVAC module- DATC (Dual Automatic Temperature Control) 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 C5.
C5 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.