Diagnostic Test

2014 Jeep Compass Limited, AWD, Automatic CVT TransSECTION Diagnostic Test
  1. CHECK FOR DTC C1020-LEFT REAR WHEEL SPEED SENSOR CIRCUIT 
    NOTE:

    This DTC must be active for the results of this test to be valid.

    1. Turn the ignition on.
    2. With the scan tool, record and erase DTCs.
    3. Cycle the ignition switch from off to on.
    4. With the scan tool, read DTCs.

      Does the scan tool display: C1020-LEFT REAR WHEEL SPEED SENSOR CIRCUIT active?

      Yes 

      • Go To  2

      No 

      • The condition that caused the symptom is currently not present. Inspect the related wiring for a possible intermittent condition. Look for any chafed, pierced, pinched, or partially broken wires.
      • Perform the ABS-INTERMITTENT CONDITION TEST. Refer to STANDARD PROCEDURE .
  2. CHECK CONNECTOR/TERMINAL FOR DAMAGE 
    NOTE:

    Check all terminals for broken, bent, pushed out, or corroded terminals.

    1. Turn the ignition off.
    2. Inspect the Anti-Lock Brake Module harness connector, Left Rear WSS, and Left Rear WSS harness connector.

      Is the Left Rear WSS or any of the connectors/terminals damaged?

      Yes 

      No 

      • Go To  3
  3. CHECK (B4) LEFT REAR WSS 12 VOLT SUPPLY CIRCUIT VOLTAGE 
    Fig 1: Measuring Voltage Of Left Rear WSS 12 Volt Supply Circuit
    GC0099363Courtesy of CHRYSLER GROUP, LLC
    1. Disconnect the Left Rear WSS harness connector.
    2. Turn the ignition on.
    3. Measure the voltage of the (B4) Left Rear WSS 12 Volt Supply circuit.

      Is the voltage above 10.0 volts?

      Yes 

      • Go To  6

      No 

      • Go To  4
  4. CHECK (B4) LEFT REAR WSS 12 VOLT SUPPLY CIRCUIT FOR A SHORT TO GROUND 
    Fig 2: Checking Left Rear WSS Supply Circuit For A Short To Ground
    GC0099364Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. Disconnect the Left Rear WSS harness connector.
    3. Disconnect the Anti-Lock Brake Module harness connector.
    4. Using a 12-volt test light connected to 12-volts, probe the (B4) Left Rear WSS Supply circuit.

      Does the test light illuminate brightly?

      Yes 

      • Repair the (B4) Left Rear WSS Supply circuit for a short to ground.
      • Perform the ABS VERIFICATION TEST. Refer to STANDARD PROCEDURE .

      No 

      • Go To  5
  5. CHECK (B4) LEFT REAR WSS 12 VOLT SUPPLY CIRCUIT FOR AN OPEN 
    Fig 3: Checking Left Rear WSS 12 Volt Supply Circuit For An Open
    GC0099364Courtesy of CHRYSLER GROUP, LLC
    1. Connect a jumper wire between ground and the (B4) Left Rear WSS Supply circuit in the Anti-Lock Brakes Module harness connector.
    2. Using a 12-volt test light connected to 12-volts, probe the (B4) Left Rear WSS Supply circuit.

      Does the test light illuminate brightly?

      Yes 

      • Replace the Anti-Lock Brakes Module in accordance with the Service Information.
      • Perform the ABS VERIFICATION TEST. Refer to STANDARD PROCEDURE .

      No 

      • Repair the (B4) Left Rear WSS Supply circuit for an open.
      • Perform the ABS VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  6. CHECK (B3) LEFT REAR WSS SIGNAL CIRCUIT FOR A SHORT TO GROUND 
    Fig 4: Checking Left Rear WSS Signal Circuit For A Short To Ground
    GC0099365Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. If not done previously, disconnect the Anti-Lock Brake Module harness connector.
    3. Turn the ignition on.
    4. Using a 12-volt test light connected to 12-volts, probe the (B3) Left Rear WSS Signal circuit.

      Does the test light illuminate brightly?

      Yes 

      • Repair the (B3) Left Rear WSS Signal circuit for a short to ground.
      • Perform the ABS VERIFICATION TEST. Refer to STANDARD PROCEDURE .

      No 

      • Go To  7
  7. CHECK (B3) LEFT REAR WSS SIGNAL CIRCUIT FOR AN OPEN 
    Fig 5: Checking Left Rear WSS Signal Circuit For An Open
    GC0099365Courtesy of CHRYSLER GROUP, LLC
    1. Connect a jumper wire between ground and the (B3) Left Rear WSS Signal circuit in the Anti-Lock Brakes Module harness connector.
    2. Using a 12-volt test light connected to 12-volts, probe the (B3) Left Rear WSS Signal circuit.

      Does the test light illuminate brightly?

      Yes 

      • Go To  8

      No 

      • Repair the (B3) Left Rear WSS Signal circuit for an open.
      • Perform the ABS VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  8. CHECK (B3) LEFT REAR WSS SIGNAL CIRCUIT SHORT TO VOLTAGE 
    Fig 6: Measuring Voltage Between Left Rear WSS Signal Circuit & Ground
    GC0099366Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition on.
    2. Remove all jumper wires.
    3. Measure the voltage between the (B3) Left Rear WSS Signal circuit and ground.

      Is the voltage above one volt?

      Yes 

      • Repair the (B3) Left Rear WSS Signal circuit for a short to voltage.
      • Perform the ABS VERIFICATION TEST. Refer to STANDARD PROCEDURE .

      No 

      • Go To  9
  9. CHECK (B3) LEFT REAR WSS SIGNAL CIRCUIT AND (B4) LEFT REAR WSS 12 VOLT SUPPLY CIRCUIT SHORTED TOGETHER 
    Fig 7: Measuring Resistance Between Left Rear WSS Signal Circuit & Left Rear WSS Supply Circuit
    GC0099367Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. Measure the resistance between the (B3) Left Rear WSS Signal circuit and the (B4) Left Rear WSS Supply circuit.

      Is the resistance above 5.0 Ohms?

      Yes 

      Go To  10

      No 

      • Repair the (B3) Left Rear WSS Signal circuit and the (B4) Left Rear WSS Supply circuit for a short together.
      • Perform the ABS VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  10. LEFT REAR WHEEL SPEED SENSOR 
    1. Replace the Left Rear Wheel Speed Sensor in accordance with the Service Information.
    2. Perform the ABS VERIFICATION TEST. Refer to STANDARD PROCEDURE .
      WARNING:

      To avoid possible serious or fatal injury, check brake capability is available before road testing.

    3. Road test the vehicle over 40 km/h (25 mph.).
      NOTE:

      Vehicle must be driven above 40 km/h (25 mph) for set conditions to be met.

    4. With the scan tool, read ABS DTCs.

      Did DTC C1020-LEFT REAR WHEEL SPEED SENSOR CIRCUIT reset?

      Yes 

      • Replace the Anti-Lock Brakes Module in accordance with the Service Information.
      • Perform the ABS VERIFICATION TEST. Refer to STANDARD PROCEDURE .

      No 

      • Test Complete.
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.