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Home >> Jeep >> 2018 >> Grand Cherokee Laredo, RWD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 11 (3.0L Diesel - DTCS P24F3-00 To U3017-00) >> DTC Troubleshooting >> P257E-00-Engine Hood Switch Circuit Low >> Diagnostic Test

Diagnostic Test

WARNING: This page is about a different variant/trim than selected.
  1. CHECK FOR AN ACTIVE DTC 
    1. Start the engine and test drive the vehicle with Start/Stop enabled.
    2. With the scan tool, view PCM DTCs.

      Is the DTC active?

      Yes 

      • Go To  2

      No 

      • Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT DTC .
  2. CHECK THE (G70) HOOD AJAR SWITCH SENSE CIRCUIT FOR A SHORT TO GROUND 
    1. Turn the ignition off.
    2. Disconnect the Hood Ajar Switch (Hood Latch) harness connector.
    3. Disconnect the BCM harness connector A.
    4. Measure the resistance between ground and the (G70) Hood Ajar Switch Sense circuit at the BCM harness connector A.

      Is the resistance above 10k Ohms?

      Yes 

      • Go To  3

      No 

      • Repair the (G70) Engine Hood Switch Sense Signal circuit for a short to ground.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
  3. CHECK THE (K806) ENGINE HOOD SWITCH 2 SIGNAL CIRCUIT FOR A SHORT TO GROUND 
    1. Disconnect the PCM C2 harness connector.
    2. Measure the resistance between ground and the (K806) Engine Hood Switch 2 Signal circuit at the PCM C2 harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  4

      No 

      • Repair the (K806) Engine Hood 2 Signal circuit for a short to ground.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
  4. CHECK THE HOOD AJAR SWITCH OPERATION 
    1. Depress the plunger of the hood ajar switch and measure the resistance between the two terminals of the switch.

      Is the resistance approximately 1000 Ohms?

      Yes 

      • Go To  5

      No 

  5. CHECK RELATED HARNESS CONNECTIONS 
    1. Disconnect all BCM 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 BCM 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