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Home >> Jeep >> 2014 >> Wrangler Sahara, Standard Trans >> Repair and Diagnosis >> Engine Mechanical >> Starter >> Starting - Non-DTC Based Diagnostics >> Diagnosis And Testing >> No Crank (TIPM - WCM Equipped) >> Diagnostic Test

Diagnostic Test

  1. STARTER RELAY CHECK 
    1. When attempting to start the vehicle, listen and if needed feel for a click at the starter relay.
      NOTE:

      Some starter relays are internal to a module and may not be accessible, making it more difficult to hear, or feel the clicking response. It is possible for a poor ground or Trans Range Sensor position could be lost causing the starter to click once.

      Did you hear an audible click at the relay or starter?

      Yes 

      • Go To  9

      No 

      • Go To  2
  2. STARTER RELAY INPUT CHECK 
    1. Using a 12 volt test light/DVOM to check for power at/going to pin 85 of the starter relay.

      Is there Power/12 volts at pin 85?

      Yes 

      • Go To  8

      No 

      • Go To  3
  3. WCM OPERATION 
    1. Using the scan tool, confirm the ignition switch status changes in the WCM under the data display screen, when using the key in the ignition.

      Does the ignition switch status on the data screen match the physical position of the key in the Ignition?

      Yes 

      • Go To  5

      No 

      • Go To  4
  4. REMOTE START ANTENNA 
    NOTE:

    If the vehicle is not equipped with Remote Start, proceed to the next test step.

    1. Turn the ignition off.
    2. Disconnect the Remote Start Antenna from the WCM.
    3. Using one Key and sitting in the driver's seat, attempt to start the vehicle.

      Did the vehicle start?

      Yes 

      • Replace the Remote Start Antenna in accordance with the Service Information.
      • Perform the BODY VERIFICATION TEST. Refer to appropriate ELECTRICAL DIAGNOSTICS article.

      No 

      • Go To  5
  5. TIPM IGNITION STATUS 
    1. Using the scan tool, confirm the ignition switch status changes in the TIPM under the data display screen for the "Bussed Input" and "Sensor" values.
      NOTE:

      The change of status in the TIPM for the "Sensor" value validates the voltage activity (with very low amperage) of the F20 circuit.

      In the TIPM, do both values for the ignition switch status match; and do they match those in the WCM?

      Yes 

      • Go To  6

      No 

      • If the status of the Ignition Switch position is not changing under the "Sensor" value, check the F20 circuit at the WCM and TIPM for battery voltage with a DVOM (not a test light). The Ignition switch sends the voltage to the WCM and TIPM simultaneously on the F20 circuit.
      • If only one module (WCM or TIPM) receives Battery voltage on the F20 circuit, repair or replace the circuit for a short/open/high resistance in accordance with Service Information.
      • If there is NO Battery voltage at the WCM and TIPM on the F20 circuit, then check for voltage on the F20 circuit at the Ignition Switch. If there is voltage on the F20 circuit at the Ignition Switch repair or replace the circuit for a short/open/high resistance. If there is no voltage on the F20 circuit when checked at the ignition switch, verify the power and ground for the Ignition Switch. If no problem found replace the switch and verify the repair.
      • In the data display screen of the WCM, if the status of the Ignition Switch Sense voltage was not changing further diagnosis is needed on the G20 Ignition Switch Sense circuit for a short/open/high resistance in accordance with Service Information.
      • In the data display screen of the TIPM, if the status of the Ignition Switch Sense voltage was not changing under the "Bussed Input" value, further diagnosis is needed on the communication for the WCM, Bus circuits, Connections and the TIPM for the cause.
  6. PCM IGNITION, TRANS RANGE/CLUTCH SWITCH STATUS VERIFICATION 
    1. Using the scan tool confirm there are no inhibits that have been triggered in the PCM (i.e. Ignition Switch, Trans Range or Clutch Switch) and any switch inputs (filtered states) relating to the starting system function and operate correctly under the data display screen.

      Does the PCM show any inhibits (not DTCs  ) for starting (not remote starting  )?

      Yes 

      No 

      • Go To  7
  7. TIPM TO STARTER RELAY CHECK 
    1. At this time if all the correct inputs for the ignition switch status are correct in the WCM, TIPM and PCM, verify both powers (pin 30 and 85) to the Starter Relay in the crank position.

      Are both power supplies present at the relay when the ignition is in the crank position?

      Yes 

      • Go To  8

      No 

  8. STARTER RELAY CONTROL CIRCUIT CHECK 
    1. Using a test light/DVOM determine if the Starter Control circuit at pin 86 of the relay is missing (at the relay if equipped with a removable relay or wiring to the internal relay) when turning the ignition to the crank position.

      Was the Starter Control circuit for pin 86 being grounded when the ignition was in the crank position?

      Yes 

      • Go To  10

      No 

      • Verify the Starter Relay Control circuit from pin 86, that there are no shorts, opens or high resistance on the wiring going from the Starter Relay in the TIPM to the PCM, Starter Solenoid and Starter.
      • Verify the cables do not have excessive resistance by performing a voltage drop on the battery cables.
  9. STARTER RELAY OUTPUT CIRCUIT CHECK 
    NOTE:

    At this point in the test, when the key is in the crank position power has been verified at Pin 30 & 85, along with the control circuit being grounded for pin 86.

    1. Remove Starter Relay Output circuit connector from the Starter solenoid.
    2. Reinstall/Connect the starter relay into the TIPM.
    3. Using a test light/DVOM and ignition in the crank position check for power at pin 87 (If equipped with a removable relay or wiring to the internal relay) of the relay and at the connection to the starter.

      Was there power at pin 87 for the output circuit?

      Yes 

      • Go To  10

      No 

      • If power is missing to pin 30 of the starter relay the TIPM is suspect. Verify all power, ground, communication circuits and connections to the TIPM before replacing in accordance with service information.
      • If power is missing at pin 87 of the starter relay and the relay is replaceable, change out the relay and recheck the concern. If a known good relay causes no change, check the Starter Output circuit from pin 87 of the relay to the starter for an open, short, excessive resistance, or poor connections to the solenoid or starter.
      • Verify and Inspect the Starter to ensure it is free of corrosion, oil, and there is no damage, or binding conditions.
      • Verify that all wiring, cables and connections are clean and tight.
  10. STARTER RELAY OUTPUT CIRCUIT CHECK 
    1. Load test the Starter Relay output circuit going from the TIPM to the Starter.

      Does the starter relay output circuit pass the load test?

      Yes 

      • Verify that all connections are clean, tight and there is no damage to starter when fully inspected. If no problem found then replace the Starter in accordance with Service Information. Refer to STARTER, REMOVAL .

      No 

      • Adjust the shift cable in accordance with the Service Information. Perform the POWERTRAIN VERIFICATION TEST. Refer to appropriate ELECTRICAL DIAGNOSTICS article.
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