TD10 - Diagnostic Trouble Code 634

Continuous Memory Diagnostic Trouble Code (DTC) 634 indicates that the Powertrain Control Module (PCM) has detected an invalid combination of transmission range switch states.

NOTE: Park/Neutral Position (PNP) switch is considered a transmission range switch in this Pinpoint Test.

- Test drive vehicle with gear selector in both Drive (0) and Overdrive (OD) positions. Check to see if transmission is always in 3rd gear with selector in the D or OD position.

- With the gear selector in D and OD position, is transmission always in 3rd gear?

Yes -- Go to TD11.

No -- If symptom is "Transmission stays in 3rd gear occasionally," Go to TD20.

For all other symptoms, disregard Continuous DTC 634. Clear continuous memory.

Return to Diagnosis by Symptom (Diagnostic Routines) to address symptom/other DTCs as necessary. Symptom Related Diagnostic Procedures