Diagnostic Test

2008 Jeep Compass Limited, FWD, StandardSECTION Diagnostic Test
  1. BRAKE FLUID LEVEL SWITCH SIGNAL VOLTAGE ABOVE 4.9 VOLTS 
    NOTE: This DTC must be active for the results of this test to be valid.

    Turn the ignition on.

    With the scan tool, read Fuel Level Switch Signal voltage.

    Is the voltage above 4.9 volts? 

    Yes 

    1. Go To  2.

    No 

    1. Refer to the ABS-INTERMITTENT CONDITION  test.
  2. (B20) BRAKE FLUID LEVEL SWITCH SIGNAL CIRCUIT FOR SHORT TO BATTERY VOLTAGE 
    Fig 1: Measuring Voltage Of (B20) Brake Fluid Level Signal Circuit In Brake Fluid Level Switch Harness Connector To Ground
    GC0053085Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the Brake Fluid Level Switch harness connector.

    Turn the ignition on.

    Measure the voltage of the (B20) Brake Fluid Level signal circuit in the Brake Fluid Level Switch harness connector to ground.

    Is the voltage above 5.2 volts? 

    Yes 

    1. Repair the (B20) Brake Fluid Level signal circuit for a short to voltage.
    2. Perform ABS VERIFICATION TEST .

    No 

    1. Go To  3.
  3. BRAKE FLUID LEVEL SWITCH INTERNAL FAILURE 
    Fig 2: Connecting Jumper Wire Between Brake Fluid Level Signal Circuit And Ground Circuit
    GC0053086Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Connect a jumper wire between the (B20) Brake Fluid Level signal circuit and the (Z925) Brake Fluid Level ground circuit in the Brake Fluid Level Switch harness connector

    Turn the ignition on.

    With the scan tool, read the Brake Fluid Level Switch voltage.

    Is the voltage below 1.0 volt? 

    Yes 

    1. Replace the Brake Fluid Level Switch in accordance with the Service Information.
    2. Perform ABS VERIFICATION TEST .

    No 

    1. Go To  4.
  4. (B20) BRAKE FLUID LEVEL SWITCH CIRCUIT OPEN 
    Fig 3: Measuring Resistance Of (B20) Brake Fluid Level Signal Circuit Between Brake Fluid Level Switch Harness Connector And TIPM Harness Connector
    GC0053087Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the Brake Fluid Level Switch.

    Disconnect the TIPM harness connector.

    Measure the resistance of the (B20) Brake Fluid Level signal circuit between the Brake Fluid Level Switch harness connector and the TIPM harness connector.

    Is the resistance below 5 ohms? 

    Yes 

    1. Go To  5.

    No 

    1. Repair the open in the (B20) Brake Fluid Level Switch signal circuit.
    2. Perform ABS VERIFICATION TEST .
  5. (Z925) SENSOR GROUND CIRCUIT OPEN 
    Fig 4: Measuring Resistance Of (Z925) Brake Fluid Level Switch Ground Circuit Between Brake Fluid Level Switch Harness Connector And Ground
    GC0053088Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the Brake Fluid Level Switch harness connector.

    Reconnect the TIPM harness connector.

    Measure the resistance of the (Z925) Brake Fluid Level Switch ground circuit between the Brake Fluid Level Switch harness connector and ground.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Replace and program the Totally Integrated Power Module in accordance with the Service Information.
    2. Perform ABS VERIFICATION TEST .

    No 

    1. Repair the open in the (Z925) Sensor ground circuit.
    2. Perform ABS VERIFICATION TEST .
RENDER: 1.0x

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.