Diagnostic Test

WARNING: This page is about a different car, the 2014 Dodge Journey. However, it is still accessible from the selected car via links, so may be relevant.

ACTIVE DTC
NOTE:
Diagnose and repair any CAN bus, communication or implausible signal DTCs before proceeding with this test.

NOTE:
Diagnose and repair any system voltage or sensor supply 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 SPECIFICATIONS .
1. Start the engine and allow it to reach normal operating temperature.
  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. With the scan tool, select View DTCs.
  Is the DTC Active at this time?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
(F855) 5 VOLT SUPPLY CIRCUIT VOLTAGE CHECK

Fig 1: Checking 5 Volt Supply Circuit Voltage
Courtesy of CHRYSLER GROUP, LLC
1. Turn the ignition off.
2. Disconnect the A/C Pressure Transducer harness connector.
3. Turn the ignition on.
4. Measure the voltage of the (F855) 5-volt Supply circuit in the A/C Pressure Transducer harness connector.
  Is the voltage above 4.5 Volts?
  
  Yes
  - Go To 6
  No
  - Go To 3
(F855) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND

Fig 2: Checking 5-Volt Supply Circuit For Short To Ground
Courtesy of CHRYSLER GROUP, LLC
1. Turn the ignition on.
2. Disconnect the PCM C2 harness connector.
3. Measure the resistance between ground and the (F855) 5-volt Supply circuit in the A/C Pressure Transducer harness connector.
  Is the resistance above 1000 Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the (F855) 5-volt Supply circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
(F855) 5-VOLT SUPPLY CIRCUIT SHORTED TO THE (K914) SENSOR GROUND CIRCUIT

Fig 3: Checking 5-Volt Supply Circuit For Short To Sensor Ground Circuit
Courtesy of CHRYSLER GROUP, LLC
1. Measure the resistance between the (F855) 5-volt Supply circuit and the (K914) Sensor Ground circuit in the A/C Pressure Transducer harness connector.
  Is the resistance above 100 Ohms?
  
  Yes
  - Go To 5
  No
  - Repair the short between the (F855) 5-volt Supply circuit and the (K914) Sensor Ground circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
(F855) 5-VOLT SUPPLY CIRCUIT OPEN OR HIGH RESISTANCE

Fig 4: Checking 5-Volt Supply Circuit For An Open Or High Resistance
Courtesy of CHRYSLER GROUP, LLC
1. Measure the resistance of the (F855) 5-volt Supply circuit between the A/C Pressure Transducer harness connector and the PCM C2 harness connector.
  Is the resistance below 5.0 Ohms?
  
  Yes
  - Go To 10
  No
  - Repair the (F855) 5-volt Supply circuit for an open circuit or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
(C18) A/C PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO GROUND

Fig 5: Checking A/C Pressure Sensor Signal Circuit For Short To Ground
Courtesy of CHRYSLER GROUP, LLC
1. Turn the ignition off.
2. Disconnect the PCM C1 harness connector.
3. Measure the resistance between ground and the (C18) A/C Pressure Sensor Signal circuit in the A/C Pressure Transducer harness connector.
  Is the resistance above 100 Ohms?
  
  Yes
  - Go To 7
  No
  - Repair the (C18) A/C Pressure Sensor Signal circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
(C18) A/C PRESSURE SENSOR SIGNAL CIRCUIT SHORTED TO THE (K914) SENSOR GROUND CIRCUIT

Fig 6: Checking A/C Pressure Sensor Signal Circuit For Short To A/C Pressure Sensor Ground Circuit
Courtesy of CHRYSLER GROUP, LLC
1. Measure the resistance between the (C18) A/C Pressure Sensor Signal circuit and the (K914) Sensor Ground circuit in the A/C Pressure Transducer harness connector.
  Is the resistance above 100 Ohms?
  
  Yes
  - Go To 8
  No
  - Repair the (C18) A/C Pressure Sensor Signal circuit for a short to the (K914) Sensor Ground circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
(C18) A/C PRESSURE SENSOR SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE

Fig 7: Checking A/C Pressure Sensor Signal Circuit For Open Or High Resistance
Courtesy of CHRYSLER GROUP, LLC
1. Measure the resistance of the (C18) A/C Pressure Sensor Signal circuit between the A/C Pressure Transducer harness connector and the PCM C1 harness connector.
  Is the resistance below 5.0 Ohms?
  
  Yes
  - Go To 9
  No
  - Repair the (C18) A/C Pressure Sensor Signal circuit for an open circuit or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
AC PRESSURE TRANSDUCER

Fig 8: A/C Pressure Transducer Harness Connector End View
Courtesy of CHRYSLER GROUP, LLC
1. Turn the ignition off.
2. Connect the PCM C1 and C2 harness connectors
3. Connect a jumper wire between the (F855) 5-volt Supply circuit and the (C18) A/C Pressure Sensor Signal circuit in the A/C Pressure Transducer harness connector.
4. Turn the ignition on.
5. With the scan tool, read the AC Pressure Transducer signal voltage.
  Is the voltage above 4.5 Volts with the jumper wire in place?
  
  Yes
  - Replace the A/C Pressure Transducer in accordance with the Service Information. Refer to TRANSDUCER, A/C PRESSURE, REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
  No
  - Go To 10
POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the A/C Pressure Transducer 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. Perform any Technical Service Bulletins that may apply.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
  No
  - Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .