A/C Pressure Sensor High (BCM)
A/C PRESSURE SENSOR HIGH (BCM)
For a complete wiring diagram refer to Diagrams/Electrical.
- When Monitored:
With the ignition on.
- Set Condition:
The Body Control Module (BCM) will set this DTC if voltage goes above 4.92 volts for more than 5 seconds on the (C18) A/C Pressure Sensor Signal circuit.
Diagnostic Test
1. CHECK THE A/C PRESSURE TRANSDUCER VOLTAGE
NOTE: Verify that the A/C Refrigerant System is properly charged before proceeding.
Start the engine.
With the scan tool, read the A/C Pressure Transducer voltage.
Is the voltage above 4.6 volts?
Yes
- Go To 2
No
- Go To 7
2. CHECK THE (C18) A/C PRESSURE SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE
Turn the ignition off.
Disconnect the A/C Pressure Transducer harness connector.
Turn the ignition on.
Measure the voltage of the (C18) A/C Pressure Signal circuit.
Is the voltage above 5.2 volts?
Yes
- Repair the (C18) A/C Pressure Signal circuit for a short to voltage.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
No
- Go To 3
3. CHECK THE (C18) A/C PRESSURE SIGNAL CIRCUIT FOR A SHORT TO THE (K301) 5-VOLT SUPPLY CIRCUIT
Turn the ignition off.
Disconnect the BCM C2 harness connector.
Measure the resistance between the (C18) A/C Pressure Signal circuit and the (K301) 5-Volt Supply circuit in the A/C Pressure Transducer harness connector.
Is the resistance below 10k ohms?
Yes
- Repair the (C18) A/C Pressure Signal circuit for a short to the (K301) 5-Volt Supply circuit.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
No
- Go To 4
4. CHECK THE (C18) A/C PRESSURE SIGNAL CIRCUIT & THE (K310) SENSOR GROUND CIRCUIT FUNCTION
Reconnect the BCM C2 harness connector.
Connect a jumper wire between the (C18) A/C Pressure Signal circuit and the (K310) Sensor Ground circuit.
Turn the ignition on.
With the scan tool, read the A/C Pressure Transducer voltage.
Is the voltage below 1.0 volt?
Yes
- Replace the A/C Pressure Transducer.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
No
- Go To 5
5. CHECK THE (C18) A/C PRESSURE SIGNAL CIRCUIT FOR AN OPEN
Turn the ignition off.
Remove the jumper wire from the A/C Pressure Transducer harness connector.
Disconnect the BCM C2 harness connector.
Measure the resistance of the (C18) A/C Pressure Signal circuit between the A/C Pressure Transducer harness connector and the BCM C2 harness connector.
Is the resistance below 5.0 ohms?
Yes
- Go To 6
No
- Repair the (C18) A/C Pressure Signal circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
6. CHECK THE (K310) SENSOR GROUND CIRCUIT FOR AN OPEN
Measure the resistance of the (K310) Sensor Ground circuit between the A/C Pressure Transducer harness connector and the BCM C2 harness connector.
Is the resistance below 5.0 ohms?
Yes
- Replace and program the BCM.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
No
- Repair the (K310) Sensor Ground circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
7. TEST FOR INTERMITTENT CONDITION
NOTE: The condition that set this DTC is not present at this time. The following may help in identifying the cause of the intermittent condition.
Check the Technical Service Bulletins (TSBs) for related concerns.
Turn the ignition on.
Using the scan tool, erase the BCM DTCs.
Turn the ignition off, wait 10 seconds, then turn the ignition on.
Monitor the scan tool for DTCs while wiggling the related wiring harness.
Turn the ignition off.
Using the wiring diagram/schematic as a guide, inspect the related wiring and connectors for chaffed, pierced, pinched, and partially broken wires, and for broken, bent, pushed out, corroded, and contaminated terminals. Repair as necessary.
Perform a voltage drop test on the related circuits between the component and the BCM.
If numerous DTCs were set, use the wiring diagram/schematic to check for common ground and supply circuits.
Were any problems found?
Yes
- Repair as necessary.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
No
- Test Complete.