Diagnostic Test

WARNING: This page is about a different car, the 2012 RAM Pickup and 2012 RAM Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

(A919) (A918) PCM FUSED B+ CIRCUITS

Fig 1: Checking The PCM Fused B+ Circuits
Courtesy of CHRYSLER GROUP, LLC

NOTE:
The scan tool and cable must be operating properly for the results of this test to be valid.

NOTE:
Make sure the ignition switch was on while trying to communicate with the PCM.
1. Turn the ignition off.
2. Disconnect the PCM harness connectors.
  CAUTION:
  Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the PCM Pinout Box (special tool #8815A, Kit, NGC, 38 Position) to perform diagnosis.
3. Using a 12-volt test light connected to ground probe the appropriate terminal of special tool #(special tool #8815A, Kit, NGC, 38 Position).
  Does the test light illuminate brightly?
  
  Yes
  - Go To 2.
  No
  - Repair the open or short to ground in the (A919) Fused B+ circuit. Inspect and replace fuses as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 1500 & 2500 - 3.7L, 4.7L & 5.7L - POWERTRAIN VERIFICATION TEST or 3500 CAB & CHASSIS - POWERTRAIN VERIFICATION TEST .
(F202), (F1), (T751) PCM FUSED IGNITION SWITCH CIRCUITS

Fig 2: Measuring Voltage Of The PCM Fused Ignition Circuits
Courtesy of CHRYSLER GROUP, LLC
1. Using a 12-volt test light connected to ground, probe the PCM Fused Ignition Switch Output circuits in the appropriate terminals of special tool #(special tool #8815A, Kit, NGC, 38 Position).
  Does the test light illuminate brightly?
  
  Yes
  - Go To 3.
  No
  - Repair the (F202) (F1) (T751) Ignition Switch Output circuits. Inspect and replace fuses as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 1500 & 2500 - 3.7L, 4.7L & 5.7L - POWERTRAIN VERIFICATION TEST or 3500 CAB & CHASSIS - POWERTRAIN VERIFICATION TEST .
(Z130), (Z131), AND (Z951) PCM GROUND CIRCUITS

Fig 3: Measuring Voltage Of The PCM Ground Circuits
Courtesy of CHRYSLER GROUP, LLC
1. Using a 12-volt test light connected to battery voltage, probe the (Z130) (Z131) PCM ground circuits in the appropriate terminals of special tool #(special tool #8815A, Kit, NGC, 38 Position).
  Does the test light illuminate brightly?
  
  Yes
  - Go To 4.
  No
  - Repair the PCM ground circuits.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 1500 & 2500 - 3.7L, 4.7L & 5.7L - POWERTRAIN VERIFICATION TEST or 3500 CAB & CHASSIS - POWERTRAIN VERIFICATION TEST .
(F855) 5-VOLT SUPPLY CIRCUIT

Fig 4: Measuring Voltage On CKP Sensor 5-Volt Supply Circuit
Courtesy of CHRYSLER GROUP, LLC
1. Turn the ignition off.
2. Connect the PCM harness connectors.
3. Disconnect the Crankshaft Position Sensor harness connector.
4. Ignition on, engine not running.
5. Measure the voltage on the (F855) 5-volt Supply circuit.
  Is the voltage between 4.5 and 5.2 volts?
  
  Yes
  - Go To 5.
  No
  - Go To 6.
CKP SENSOR

Fig 5: Measuring Voltage On Primary 5-Volt Supply Circuit At Throttle Body Harness Connector
Courtesy of CHRYSLER GROUP, LLC
1. Turn the ignition off.
2. Disconnect the Throttle Body Harness connector.
3. Ignition on, engine not running.
4. Measure the voltage on the (F855) 5-volt Supply circuit in the Throttle Body harness connector.
  Is the voltage between 4.5 and 5.2 volts?
  
  Yes
  - If communication is available with a PCM on a like vehicle, replace and program the Powertrain Control Module per Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 1500 & 2500 - 3.7L, 4.7L & 5.7L - POWERTRAIN VERIFICATION TEST or 3500 CAB & CHASSIS - POWERTRAIN VERIFICATION TEST .
  No
  - Replace the Crankshaft Position Sensor.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 1500 & 2500 - 3.7L, 4.7L & 5.7L - POWERTRAIN VERIFICATION TEST or 3500 CAB & CHASSIS - POWERTRAIN VERIFICATION TEST .
(F855) 5-VOLT SENSOR OPEN/SHORTED

Fig 6: Measuring Voltage On Primary 5-Volt Supply Circuit At Throttle Body Harness Connector
Courtesy of CHRYSLER GROUP, LLC
1. Turn the ignition off.
2. Disconnect the Throttle Body harness connector.
3. Ignition on, engine not running.
4. Measure the voltage on the (F855) 5-volt Supply circuit.
5. Disconnect all the sensors that use the (F855) 5-volt Supply circuit.
  Did the voltage return to 4.5 to 5.2 volts when disconnecting any of the sensors.
  
  Yes
  - Replace the sensor that is pulling down the (F855) 5-volt supply.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 1500 & 2500 - 3.7L, 4.7L & 5.7L - POWERTRAIN VERIFICATION TEST or 3500 CAB & CHASSIS - POWERTRAIN VERIFICATION TEST .
  No
  - Go To 7.
(F855) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
1. Turn the ignition off.
2. Disconnect C2 PCM harness connector.
3. Disconnect all the sensors that share the (F855) 5-volt Supply circuit.
4. Measure the resistance between ground and the (F855) 5-volt Supply circuit at one of the sensor harness connectors.
  Is the resistance below 100 ohms?
  
  Yes
  - Repair the short to ground in the (F855) 5-volt Supply circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 1500 & 2500 - 3.7L, 4.7L & 5.7L - POWERTRAIN VERIFICATION TEST or 3500 CAB & CHASSIS - POWERTRAIN VERIFICATION TEST .
  No
  - Go To 8.
(F856) 5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
1. Disconnect all the sensors that share the (F856) 5-volt Supply circuit.
2. Measure the resistance between ground and the (F856) 5-volt Supply circuit at one of the sensor harness connectors.
  Is the resistance below 100 ohms?
  
  Yes
  - Repair the short to ground in the (F856) 5-volt Supply circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 1500 & 2500 - 3.7L, 4.7L & 5.7L - POWERTRAIN VERIFICATION TEST or 3500 CAB & CHASSIS - POWERTRAIN VERIFICATION TEST .
  No
  - Go To 9.
POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the related Sensors 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. Verify that there is good pin to terminal contact in the related Sensors and the Powertrain Control Module connectors.
4. Refer to any Technical Service Bulletins that may apply.
  Were there any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 1500 & 2500 - 3.7L, 4.7L & 5.7L - POWERTRAIN VERIFICATION TEST or 3500 CAB & CHASSIS - POWERTRAIN VERIFICATION TEST .
  No
  - Replace and program the Powertrain Control Module per Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to 1500 & 2500 - 3.7L, 4.7L & 5.7L - POWERTRAIN VERIFICATION TEST or 3500 CAB & CHASSIS - POWERTRAIN VERIFICATION TEST .