Diagnostic Test

CHECK FOR AN ACTIVE DTC
NOTE:
Diagnose and repair any system voltage or sensor reference voltage DTCs before continuing with this test.

NOTE:
Make sure the A/C refrigerant System is properly charged in accordance with the Service Information. Refer to TECHNICAL SPECIFICATIONS .
1. Start the engine and allow it to idle.
  WARNING:
  When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in possible serious or fatal injury.
2. Turn on the A/C system.
3. With the scan tool, read DTCs.
  Is the DTC active?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK THE (C18) A/C PRESSURE SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the A/C Pressure Sensor harness connector.
3. Disconnect the PCM C2 harness connector.
4. Check for continuity between ground and the (C18) A/C Pressure Sensor Signal circuit at the A/C Pressure Sensor harness connector.
  Is there continuity between ground and the (C18) A/C Pressure Sensor Signal circuit?
  
  Yes
  - Repair the (C18) A/C Pressure Sensor Signal circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 3
CHECK FOR THE (C18) A/C PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO THE (K914) SENSOR GROUND CIRCUIT
1. Check for continuity between the (C18) A/C Pressure Sensor Signal circuit and the (K914) Sensor Ground circuit at the A/C Pressure Sensor harness connector.
  Is there continuity between the (C18) A/C Pressure Sensor Signal circuit and the (K914) Sensor Ground circuit?
  
  Yes
  - Repair the short between the (C18) A/C Pressure Sensor Signal circuit and the (K914) Sensor Ground circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 4
A/C PRESSURE SENSOR
1. Reconnect the PCM C2 harness connector.
2. Connect a jumper between the (C18) A/C Pressure Sensor Signal circuit and the (K854) 5-Volt Supply circuit at the A/C Pressure Sensor harness connector.
3. Turn the ignition on.
  NOTE:
  The scan tool should display the P0533-A/C PRESSURE SENSOR CIRCUIT HIGH DTC as active or pending with the jumper in place.
4. With the scan tool, read DTCs.
  Does the DTC display as described above?
  
  Yes
  - Replace the A/C Pressure Sensor in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 5
POWERTRAIN CONTROL MODULE
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the A/C Pressure Sensor and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
5. Look for the data to change or for the DTC to reset during the wiggle test.
6. Perform any Service Bulletins that may apply.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Replace the Powertrain Control Module in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .