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Diagnostic Test

WARNING: This page is about a different car, the 2014 Dodge Journey. However, it is still accessible from the selected car via links, so may be relevant.
  1. ACTIVE DTC 
    NOTE:

    Diagnose and repair any communication or low voltage DTCs before proceeding with this test.

    1. Ignition on, engine not running.
    2. With the scan tool, select View DTCs.
      NOTE:

      If DTC P258A is active along with this DTC, perform the diagnostic procedure for P258A before continuing with this DTC.

      Is the DTC Active or Pending at this time?

      Yes 

      • Go To  2

      No 

  2. ENGINE WITH ELECTRIC VACUUM PUMP 
    1. Verify vehicle is equipped with an Electric Vacuum Pump.

      Is the vehicle is equipped with an Electric Vacuum Pump?

      Yes 

      • Go To  3

      No 

      • Go To  13
  3. ELECTRIC VACUUM PUMP 
    1. Turn the ignition on.
    2. With the scan tool actuate the Electronic Vacuum Pump.

      Does the Electric Vacuum Pump run?

      Yes 

      • Go To  8

      No 

      • Go To  4
  4. CHECK THE FUSED B+ CIRCUIT 
    Fig 1: Checking Fused B+ Circuit
    GC0150250Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. Remove the EVP Relay from the relay connector in the PDC.
    3. Ignition on, engine not running.
    4. Using a 12-Volt test light connected to ground, probe the Fused B+ circuit in the EVP Relay harness connector.

      Does the test light illuminate brightly?

      Yes 

      • Go To  5

      No 

      • Replace the PDC in accordance with the service information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  5. CHECK THE (T109) ELECTRIC VACUUM PUMP OUTPUT CIRCUIT FOR AN OPEN/HIGH RESISTANCE 
    Fig 2: Checking Electric Vacuum Pump Output Circuit For Open Or High Resistance
    GC0150301Courtesy of CHRYSLER GROUP, LLC
    1. Disconnect the Electric Vacuum Pump harness connector.
    2. Measure the resistance of the (T109) Electric Vacuum Pump Output circuit between the EVP Relay connector and the Electric Vacuum Pump harness connector.

      Is the resistance below 5.0 Ohms?

      Yes 

      • Go To  6

      No 

      • Repair the (T109) Electric Vacuum Pump Output circuit for an open.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  6. CHECK THE (T109) ELECTRIC VACUUM PUMP OUTPUT CIRCUIT FOR A SHORT TO GROUND 
    Fig 3: Checking Electric Vacuum Pump Output Circuit For Short To Ground
    GC0150251Courtesy of CHRYSLER GROUP, LLC
    1. Measure the resistance between ground and the (T109) Electric Vacuum Pump Output circuit at the EVP Relay connector.

      Is the resistance above 10k Ohms?

      Yes 

      • Go To  7

      No 

      • Repair the (T109) Electric Vacuum Pump Output circuit for a short to ground.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  7. CHECK THE GROUND CIRCUIT 
    1. Using a 12-volt test light connected to 12 volts, probe the Ground circuit at the Electric Vacuum Pump harness connector.

      Does the test light illuminate brightly?

      Yes 

      • Replace the Electric Vacuum Pump in accordance with the service information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

  8. CHECK FOR PINCHED VACUUM SUPPLY LINE 
    1. Turn the ignition off.
    2. Check the vacuum supply line to brake booster for a pinched, cut or open hose.

      Were any problems found?

      Yes 

      No 

      • Go To  9
  9. VACUUM PRESSURE SIGNAL 
    1. Start the engine.
    2. With the scan tool, view and record the vacuum pressure signal with foot off the brake pedal.
    3. With the scan tool, view the vacuum pressure signal while pressing the brake pedal several times.
    4. Record the highest value.

      Without the brake pedal applied, was the vacuum pressure signal -40 kPa (12 in. Hg)?

      Yes 

      • Go To  10

      No 

  10. CHECK FOR VACUUM PRESSURE SIGNAL CHANGE 
    1. Turn the ignition on.
    2. Remove the Vacuum Pressure Sensor from the Booster.
    3. Connect a vacuum pump to the Vacuum Pressure Sensor.
    4. Apply vacuum to the Vacuum Pressure Sensor and watch for signal change.

      Is the voltage signal changing on the scan tool as vacuum is being applied?

      Yes 

      • Go To  11

      No 

      • Replace the Vacuum Pressure Sensor in accordance with the service information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  11. CHECK BRAKE BOOSTER CHECK VALVE 
    1. Remove the Brake Booster Check Valve.
    2. Apply vacuum to the booster side of the check valve.

      Is the Brake Booster Check Valve holding vacuum?

      Yes 

      • Go To  12

      No 

  12. CHECK BRAKE BOOSTER 
    1. Reinstall the Brake Booster Check Valve.
    2. Apply vacuum to the Brake Booster.

      Is the Brake Booster holding vacuum?

      Yes 

      • Go To  13

      No 

  13. ANTI-LOCK BRAKE SYSTEM (ABS) 
    1. Turn the ignition off to the lock position.
    2. Perform any Technical Service Bulletins that may apply.
    3. Inspect the related wiring harness. Look for any chafed, pierced, pinched or partially broken wires.
    4. Inspect the related wire harness connectors. Look for broken, bent, pushed out or corroded terminals.

      Were any problems found?

      Yes 

      No 

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