LEMON Manuals: Even more car manuals for everyone
Home >> Jeep >> 2018 >> Grand Cherokee Laredo, RWD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 8 (3.0L Diesel - DTCS P0627-00 To P1692-00) >> DTC Troubleshooting >> P1691-00-REDUCTANT Injection Valve Circuit High - Positive Side >> Diagnostic Test

Diagnostic Test

WARNING: This page is about a different variant/trim than selected.
  1. DTC IS ACTIVE 
    1. Ignition on, engine not running.
    2. With the scan tool, record any environmental data and record all DTCs on the repair order.
    3. With the scan tool, erase DTCs in the Powertrain Control Module (PCM).
    4. Start the engine and allow it to reach normal operating temperature.
    5. With the scan tool, select View DTCs.

      Is the status Active for this DTC?

      Yes 

      • Go To  2

      No 

      • Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT DTC .
  2. CHECK FOR OTHER DTCS 
    1. Refer to the recorded DTCs.

      Are there any DEF Supply Pump DTCs active or pending?

      Yes 

      No 

      • Go To  3
  3. CHECK THE (K428) DEF INJECTOR POSITIVE CIRCUIT FOR A SHORT TO VOLTAGE 
    1. Turn the Ignition off.
    2. Disconnect the DEF Injector harness connector.
    3. Turn the Ignition on.
    4. Measure the voltage on the (K428) DEF Injector Positive circuit at the DEF Injector harness connector.

      Is the voltage above 12.0 Volts?

      Yes 

      • Repair the (K428) DEF Injector Positive circuit for a short to voltage.
      • Perform the PCM VERIFICATION TEST. Refer to PCM VERIFICATION TEST .

      No 

      • Go To  4
  4. CHECK THE (K428) DEF INJECTOR POSITIVE CIRCUIT FOR AN OPEN/HIGH RESISTANCE 
    1. Turn the ignition off.
    2. Disconnect the PCM C2 harness connector.
    3. Measure the resistance of the (K428) DEF Injector Positive circuit between the DEF Injector harness connector and the PCM C2 harness connector.

      Is the resistance above 5.0 Ohms?

      Yes 

      • Repair the (K428) DEF Injector Positive circuit for an open/high resistance.
      • Perform the PCM VERIFICATION TEST. Refer to PCM VERIFICATION TEST .

      No 

      • Go To  5
  5. CHECK THE DEF INJECTOR FOR PROPER OPERATION 
    1. Turn the ignition off.
    2. Replace the DEF Injector in accordance with the service information.
    3. Reconnect the DEF Injector harness connector.
    4. Reconnect the PCM C2 harness connector.
    5. Turn the ignition on.
    6. With the scan tool, erase PCM DTCs.
    7. Start the engine and allow it to reach normal operating temperature.
    8. Test drive the vehicle under all normal conditions.
    9. With the scan tool, read PCM DTCs.

      Does the scan tool display this DTC?

      Yes 

      • Go To  6

      No 

  6. CHECK RELATED HARNESS CONNECTIONS 
    1. Disconnect all PCM harness connectors.
    2. Disconnect all related in-line harness connections (if equipped).
    3. Disconnect the related component harness connectors.
    4. 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.

    5. Connect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
    6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
    7. Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
    8. With the scan tool, erase DTCs.
    9. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
    10. With the scan tool, read DTCs.

      Did the DTC return?

      Yes 

      No 

      • Repair the poor connections.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .