Diagnostic Test

WARNING: This page is about a different car, the 2017 Jeep Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR AN ACTIVE DTC
1. Turn the ignition on.
2. Turn the Front Wipers on.
3. With the scan tool, read the Body Control Module (BCM) DTCs and record on the repair order.
  Is the DTC active?
  
  Yes
  - Go To 2
  No
  - The condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals and correct pin tension. If no problems are found, test complete.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
CHECK THE WIPER HIGH/LOW RELAY
NOTE:
The test light must illuminate brightly. Compare the brightness to that of a direct connection to the battery.
1. Turn the front wipers off.
2. Turn the ignition off.
3. Remove the Wiper High/Low Relay from the Front Power Distribution Center (PDC).
4. Turn the ignition on.
5. Turn the Front Wiper Switch to the high speed.
6. Using a 12-volt test light connected to ground, check the (W2) Wiper High/Low Relay Control circuit at the Wiper High/Low Relay cavity in the Front PDC.
  Does the test light illuminate brightly?
  
  Yes
  - Replace the Wiper High/Low Relay.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 3
CHECK THE (W2) WIPER HIGH/LOW RELAY CONTROL CIRCUIT FOR A SHORT TO GROUND
1. Turn the front wipers off.
2. Turn the ignition off.
3. Disconnect the BCM C4/D harness connector.
4. Measure the resistance between ground and the (W2) Wiper High/Low Relay Control circuit at the Wiper High/Low Relay cavity in the Front PDC.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Repair the (W2) Wiper High/Low Relay Control circuit for a short to ground.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 4
CHECK THE (W2) WIPER HIGH/LOW RELAY CONTROL CIRCUIT FOR AN OPEN
1. Measure the resistance of the (W2) Wiper High/Low Relay Control circuit between the BCM C4/D harness connector and the Wiper High/Low Relay cavity in the Front PDC.
  Is the resistance above 3.0 Ohms?
  
  Yes
  - Repair the (W2) Wiper High/Low Relay Control circuit for an open circuit.
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Go To 5
CHECK RELATED BCM HARNESS CONNECTIONS
1. Disconnect all BCM harness connectors.
2. Disconnect all related in-line harness connections (if equipped).
3. Disconnect the related component harness connectors.
4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
  - Proper connector installation.
  - Damaged connector locks.
  - Corrosion.
  - Other signs of water intrusion.
  - Weather seal damage (if equipped).
  - Bent terminals.
  - Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
  - Terminals that have been pushed back into the connector cavity.
  - Perform a terminal drag test on each connector terminal to verify proper terminal tension.
  Repair any conditions that are found.
5. Connect all BCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. With the scan tool, erase DTCs.
9. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
10. With the scan tool, read BCM DTCs.
  Did the DTC return?
  
  Yes
  - Replace the Body Control Module (BCM) in accordance with the Service Information. Refer to MODULE, BODY CONTROL (BCM), REMOVAL .
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  No
  - Perform the BODY VERIFICATION TEST. Refer to BODY VERIFICATION TEST .
  - Test complete.