Diagnostic Test

WARNING: This page is about a different car, the 2009 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

TEST FOR INTERMITTENT CONDITION
1. Turn the ignition on.
  NOTE: Ensure the IOD fuse is installed and battery voltage is between 10.0 and 16.0 volts.
2. With the scan tool, select ECU view.
  NOTE: A red "X" will be next to the module that is not communicating, indicating that the module is not active on the Bus network. A green check indicates that the module is active on the Bus network.
  
  NOTE: Check the FCM for any active CAN C hardware DTCs, perform DTC before proceeding.
  
  Does the scan tool display a red "X" next to the module?
  
  Yes
  - Go to step 2
  No
  - The no response condition is not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring for chafed, pierced, pinched, and partially broken wires and the wiring harness connectors for broken, bent, pushed out, and corroded terminals.
(A107) (A200) FUSED B(+) CIRCUIT OPEN OR SHORTED

Fig 1: Checking Fused B(+) Circuit For Open Or Shorted
Courtesy of CHRYSLER LLC
1. Turn the ignition off.
2. Disconnect the Antilock Brake Module harness connector.
3. Using a 12-volt test light connected to ground, check each (A107) and (A200) Fused B(+) circuit.
  Does the test light illuminate brightly for each circuit?
  
  Yes
  - Go to step 3
  No
  - Repair the Fused B(+) circuit for an open or short.
  - Perform the ABS VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure
(Z107) (Z127) GROUND CIRCUIT OPEN

Fig 2: Checking Ground Circuits For Open
Courtesy of CHRYSLER LLC
1. Using a 12-volt test light connected to 12-volts, check each (Z107) and (Z127) ground circuit.
  Does the test light illuminate brightly for each circuit?
  
  Yes
  - Go to step 4
  No
  - Repair the ground circuit for an open.
  - Perform the ABS VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure
(F943) FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN OR SHORTED

Fig 3: Checking Fused Ignition Switch Output Circuit For Open Or Shorted
Courtesy of CHRYSLER LLC
1. Turn the ignition on.
2. Using a 12-volt test light connected to ground, check the (F943) Fused Ignition Switch Output circuit.
  Does the test light illuminate brightly?
  
  Yes
  - Go to step 5
  No
  - Repair the (F943) Fused Ignition Switch Output circuit for an open or short.
  - Perform the ABS VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure
(D65) CAN C BUS (+) CIRCUIT OPEN

Fig 4: Checking Can C Bus (+) Circuit For Open
Courtesy of CHRYSLER LLC
1. Turn the ignition off.
2. Disconnect the FCM C1 harness connector.
3. Measure the resistance of the (D65) CAN C Bus (+) circuit between the FCM connector and the Antilock Brake Module connector.
  Is resistance below 5.0 ohms?
  
  Yes
  - Go to step 6
  No
  - Repair the (D65) CAN C Bus (+) circuit for an open.
  - Perform the ABS VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure
(D64) CAN C BUS (-) CIRCUIT OPEN

Fig 5: Checking Can C Bus (-) Circuit For Open
Courtesy of CHRYSLER LLC
1. Measure the resistance of the (D64) CAN C Bus (-) circuit between the FCM connector and the Antilock Brake Module connector.
  Is resistance below 5.0 ohms?
  
  Yes
  - Replace the Antilock Brake Module in accordance with the Service Information.
  - Perform the ABS VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure
  No
  - Repair the (D64) CAN C Bus (-) circuit for an open.
  - Perform the ABS VERIFICATION TEST. Refer to DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure