After on-Board Diagnostics

NOTE: The vehicle wiring harness, powertrain control module and non-transmission sensors can affect transmission operations. Repair these concerns first.

After the On-Board Diagnostics procedures are completed, repair all Diagnostics Trouble Codes (DTCs).

Always repair all non-transmission-related DTCs first, then repair any transmission-related DTCs. Refer to the Diagnostic Trouble Code Chart for information on condition and symptoms. This chart will be helpful in diagnosing internal transmission concerns and external non-transmission inputs. The pinpoint tests are used in diagnosing electrical concerns of the E40D transmission. Make sure the vehicle wiring harness and the powertrain control module are diagnosed as well.