Diagnostic Test

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. Using the scan tool, record and erase DTCs.
3. Cycle the ignition switch from off to on.
4. Using the scan tool, read DTCs.
  Does the scan tool display: C1020-LEFT REAR WHEEL SPEED SENSOR CIRCUIT?
  
  Yes
  - Go to step 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.
  - See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure and perform the ABS-INTERMITTENT CONDITION diagnostic procedure.
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
  - Repair as necessary.
  - Perform the ABS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
  No
  - Go to step 3
CHECK (B4) LEFT REAR WSS 12 VOLT SUPPLY CIRCUIT VOLTAGE

Fig 1: Checking Left Rear WSS 12 Volt Supply Circuit Voltage
Courtesy of CHRYSLER 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 step 6
  No
  - Go to step 4
CHECK (B4) LEFT REAR WSS 12 VOLT SUPPLY CIRCUIT FOR A SHORT TO GROUND

Fig 2: Checking Left Rear WSS 12 Volt Supply Circuit For A Short To Ground
Courtesy of CHRYSLER 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. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
  No
  - Go to step 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
Courtesy of CHRYSLER 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. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
  No
  - Repair the (B4) Left Rear WSS Supply circuit for an open.
  - Perform the ABS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
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
Courtesy of CHRYSLER LLC
1. Turn the ignition off.
2. If not done previously, disconnect the Anti-Lock Brake Module harness connector.
3. 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. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
  No
  - Go to step 7
CHECK (B3) LEFT REAR WSS SIGNAL CIRCUIT FOR AN OPEN

Fig 5: Checking Left Rear WSS Signal Circuit For An Open
Courtesy of CHRYSLER 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 step 8
  No
  - Repair the (B3) Left Rear WSS Signal circuit for an open.
  - Perform the ABS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
CHECK (B3) LEFT REAR WSS SIGNAL CIRCUIT SHORT TO VOLTAGE

Fig 6: Checking Left Rear WSS Signal Circuit Short To Voltage
Courtesy of CHRYSLER LLC
1. Turn the ignition on.
2. Remove all jumper wires.
3. Using a 12-volt test light connected between the (B3) Left Rear WSS Signal circuit and ground.
  Does the test light illuminate brightly?
  
  Yes
  - Repair the (B3) Left Rear WSS Signal circuit for a short to voltage.
  - Perform the ABS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
  No
  - Go to step 9
CHECK (B3) LEFT REAR WSS SIGNAL CIRCUIT AND (B4) LEFT REAR WSS 12 VOLT SUPPLY CIRCUIT SHORTED TOGETHER

Fig 7: Checking Left Rear WSS Signal Circuit & Left Rear WSS 12 Volt Supply Circuit Shorted Together
Courtesy of CHRYSLER 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 step 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. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
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. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
  CAUTION: Make sure 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 meet.
4. Using 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. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
  No
  - Test Complete.