Diagnostic Test
- CHECK FOR AN ACTIVE DTC NOTE:
Improperly installed aftermarket accessories can cause this DTC to set. Check for any improperly installed aftermarket accessories before continuing with this test.
- Turn the ignition on.
- With a scan tool, read DTCs.
Is the DTC active or pending?
Yes
- Go To 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
- CHECK THE 5-VOLT SUPPLY CIRCUIT FOR A SHORT TO GROUND
- Turn the ignition off.
- Disconnect the PCM C2 harness connector.
- Disconnect all the Sensor harness connectors that share the (F855) 5-Volt Supply circuit.NOTE:
This code can be caused by the improper installation of after market accessories that may be causing excessive noise on the (F855) 5-Volt Supply circuit.
- Check for continuity between ground and the (F855) 5-Volt Supply circuit at the CKP Sensor harness connector.
- Check for continuity between ground and the (K852) 5-Volt Supply circuit at the APP Sensor harness connector.
Is the there continuity between ground and the Primary 5-Volt Supply circuit?
Yes
- Repair the Primary 5-Volt Supply circuit for a short to ground.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 3
- SENSOR SHORTED TO GROUND
- Connect the PCM C2 harness connector and all the previously disconnected Sensor harness connectors except for the Throttle Body harness connector.
- Turn the ignition on.
- Measure the voltage on the (F855) 5-Volt Supply circuit at the Throttle Body harness connector.NOTE:
You must Turn the Ignition off when disconnecting any of the Sensor harness connectors and Turn the Ignition on to check the voltage readings.
- While monitoring the voltage, disconnect each Sensor harness connector that shares the (F855) 5-Volt Supply circuit, one at a time including the APP Sensor.
Does the voltage increase to above 4.9 volts when disconnecting any of the Sensor harness connectors?
Yes
- Verify that there is good pin to terminal contact in the related Sensor and Powertrain Control Module connectors. If OK, replace the Sensor that causes the (F855) 5-Volt Supply circuit voltage to increase when disconnected.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 4
- 5-VOLT SENSOR
- Turn the ignition off.
- Connect all the previously disconnected Sensor harness connectors except for the CKP Sensor harness connector.
- Turn the ignition on.
- Measure the voltage on the (F855) 5-Volt Supply circuit at the CKP Sensor harness connector.
Is the voltage between 4.9 and 5.1 volts?
Yes
- Verify that there is good pin to terminal contact in the CKP Sensor and Powertrain Control Module harness connectors. If OK, replace the Crankshaft Position Sensor. Refer to SENSOR, CRANKSHAFT POSITION, REMOVAL .
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 5
- CHECK THE (F855) 5-VOLT SUPPLY FOR A SHORT TO VOLTAGE
- Turn the ignition off.
- Disconnect the PCM C2 harness connector.
- Disconnect all the Sensor harness connectors that share the (F855) 5-Volt Supply circuit.
- Turn the ignition on.
- Measure the voltage on the (F855) Primary 5-Volt Supply circuit in the CKP Sensor harness connector.
- Measure the voltage on the (K852) Primary 5-Volt Supply circuit in the APP Sensor harness connector.
Is there any voltage present?
Yes
- Repair the Primary 5-Volt Supply circuit for a short to voltage.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 6
- CHECK THE (F855) 5-VOLT SUPPLY CIRCUIT FOR AN OPEN/HIGH RESISTANCE
- Turn the ignition off.
- Measure the resistance in the (F855) Primary 5-Volt Supply circuit from the Sensor harness connector to the PCM C2 harness connector.
- It may be necessary to perform this test from every sensor that uses the (F855) Primary 5-Volt Supply circuit.
Is the resistance below 3.0 Ohms?
Yes
- Go To 7
No
- Repair the (F855) Primary 5-Volt Supply circuit for an open or high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
- POWERTRAIN CONTROL MODULE (PCM)
- Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the related Sensors and the Powertrain Control Module (PCM).
- Look for any chafed, pierced, pinched, or partially broken wires.
- Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related Sensor and Powertrain Control Module connectors.
- Perform any Service Bulletins that may apply.
Were there any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL .
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .