Diagnostic Test

WARNING: This page is about a different car, the 2013 RAM 3500 HD and 2013 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.

ACTIVE DTC
1. Ignition ON, Engine Not Running.
2. With the scan tool, select view DTCs.
  Is the DTC Active at this time?
  
  Yes
  - Refer to DTC INDEX - 2500 HD & 3500 HD and perform the U0100-Lost Communication with ECM/PCM diagnostic procedure.
  No
  - Refer to DIAGNOSIS AND TESTING and perform the Stored Lost Communication DTCs diagnostic procedure.