Diagnostic Test

CHECK FOR AN ACTIVE DTC
1. With the scan tool, read Trailer Tow Module (TTM) DTCs and record on the repair order.
2. Record the Environmental Data.
3. With the scan tool, erase DTCs.
4. Using the recorded Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
5. With the scan tool, read TTM DTCs.
  Did the DTC return?
  
  Yes
  - Go To 2
  No
  - Perform the TESTING FOR INTERMITTENT CONDITIONS procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .
TRAILER TOW MODULE (TTM) INTERNAL CONDITION
1. The TTM is reporting internal errors.
  NOTE:
  Before continuing, check the harness connector terminals Repair as necessary.
2. Using the schematics as a guide, inspect the TTM wire harness and connectors for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits.
3. Perform any Technical Service Bulletins (TSB) that may apply.
  Were there any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the TTM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Go To 3
CHECK RELATED HARNESS CONNECTIONS
1. Disconnect all TTM 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. Reconnect all TTM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
6. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Reconnect 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 TTM DTCs.
  Did the DTC return?
  
  Yes
  - Replace the Trailer Tow Module (TTM) in accordance with the Service Information.
  - Perform the TTM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Perform the TTM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  - Test complete.