Diagnostic Strategy

Diagnostic Strategy
Troubleshooting an electronically-controlled automatic transaxle is simplified by using the proven method of diagnosis. One of the most important things to remember is that there is a definite procedure to follow.

NOTE: Do not take short cuts or assume that critical checks or adjustments have already been made.

Follow the procedures as written to avoid missing critical components or steps.

To correctly diagnose a concern, have these publications available:
^ Computers and Control Systems
^ Technical Service Bulletins (TSBs)
^ Wiring Diagrams

These publications provide the information required when diagnosing transaxle concerns.

Use the Diagnostic Flow Chart as a guide and follow the steps as indicated.

Preliminary Inspection
^ Know and understand the customer's concern.
^ Verify the concern by operating the vehicle.
^ Check the fluid levels and condition.
^ Check for non-factory-installed items and verify correct installation.
^ Check shift linkages for correct adjustment.
^ Check TSBs regarding the concern.
^ Carry out quick tests, both KOER and KOEO.
^ Record all codes.

Diagnostics
^ Carry out on-board diagnostic procedures key on/engine off (KOEO) and key on/engine running (KOER).
^ Record all diagnostic trouble codes (DTCs).
^ Repair all non-transaxle codes first.
^ Repair all transaxle codes second.
^ Erase all continuous codes and attempt to repeat them.
^ Repair all continuous codes.
^ If only pass codes are obtained, proceed to Diagnosis By Symptom for further information and diagnosis.

Follow the diagnostic sequence to diagnose and repair the concern the first time.