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.
1. Turn the ignition on.
2. With the scan tool, read DTCs and record on the repair order.
  Is the DTC active or pending?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK THE (F856) SECONDARY 5-VOLT SUPPLY CIRCUIT VOLTAGE
1. Turn the ignition off.
2. Disconnect the PCM C2 harness connector.
  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 GPEC Diagnostic Adaptor to perform the diagnosis.
3. Connect the (special tool #10436, Adapter, GPEC Diagnostic).
4. Reconnect the PCM C2 harness connector with the GPEC Adaptor connected in-line with the PCM C2 harness connector.
5. Turn the ignition on.
6. Measure the voltage on the (F856) Secondary 5-Volt Supply circuit at the GPEC Adaptor.
  Is the voltage between 4.9 and 5.1 volts?
  
  Yes
  - Go To 6
  No
  - Go To 3
CHECK THE SENSORS THAT SHARE THE SECONDARY 5-VOLT SUPPLY
1. IMPORTANT - FOLLOW THIS PROCEDURE EXACTLY WHEN CHECKING THE FOLLOWING COMPONENTS: Turn the ignition off before disconnecting each component. After a component has been disconnected, turn the ignition on and measure the voltage on the (F856) Secondary 5-Volt Supply circuit at the GPEC Adaptor. If the 5-Volt Supply voltage returns to 5.0 volts after disconnecting a component, the component that was disconnected is faulty. If the voltage remains low after disconnecting a component, then the disconnected component is not the problem. Leave each component disconnected and move on to the next until the faulty component is discovered or all components have been disconnected. Disconnect only one component at a time during this step.
2. Disconnect the CMP Sensor harness connector and check the Secondary 5-Volt Supply circuit voltage.
3. Disconnect the CMP Sensor 2 harness connector and check the Secondary 5-Volt Supply circuit voltage.
4. Disconnect the FRP Sensor harness connector and check the Secondary 5-Volt Supply circuit voltage.
5. Disconnect the APP Sensor harness connector and check the Secondary 5-Volt Supply circuit voltage.
6. Disconnect the EGR Valve Assembly harness connector and check the Secondary 5-Volt Supply circuit voltage.
  Were any of the above components determined to be at fault?
  
  Yes
  - Replace the faulty component in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 4
CHECK THE (F856) SECONDARY 5-VOLT SUPPLY CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
  NOTE:
  All of the components should still be disconnected during this test step.
2. Disconnect the PCM C2 harness connector from the PCM.
3. Check for continuity between ground and the (F856) Secondary 5-Volt Supply circuit at the GPEC Adaptor.
  Is there continuity between ground and the (F856) Secondary 5-Volt Supply circuit(s)?
  
  Yes
  - Repair the (F856) Secondary 5-Volt Supply circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 5
CHECK THE (K854) SECONDARY 5-VOLT SUPPLY CIRCUIT FOR A SHORT TO GROUND
1. Disconnect the PCM C1 harness connector.
2. Connect the (special tool #10436, Adapter, GPEC Diagnostic) to the PCM C1 harness connector.
3. Check for continuity between ground and the (K854) Secondary 5-Volt Supply circuit at the GPEC Adaptor.
  Is there continuity between ground and the (K854) Secondary 5-Volt Supply circuit(s)?
  
  Yes
  - Repair the (K854) Secondary 5-Volt Supply circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 6
CHECK RELATED PCM AND COMPONENT CONNECTIONS
1. Perform any Service Bulletins that apply.
2. Disconnect all PCM harness connectors.
3. Disconnect all related in-line harness connections (if equipped).
4. Disconnect the related component harness connectors.
5. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
  - Proper connector installation.
  - Damaged connector locks.
  - Corrosion.
  - Other signs of water intrusion.
  - Weather seal damage (if equipped).
  - Bent terminals.
  - Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
  - Terminals that have been pushed back into the connector cavity.
  - Check for spread terminals and verify proper terminal tension.
  Repair any conditions that are found.
6. Reconnect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
7. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
9. With the scan tool, erase DTCs.
10. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
11. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Replace the Powertrain Control Module in accordance with the Service information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  - Test complete.