4F50N (AX4N) Automatic Transaxle

Diagnostic Trouble Code Charts





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Part 9 of 9

Diagnostic Trouble Code Chart
a. May also be generated by some other non-electric transaxle hardware system.
b. Output circuit check, generated only by electrical symptoms.

Rotunda Transmission Tester
The Rotunda Transmission Tester is used to diagnose electronically controlled transaxles and is used in conjunction with the pinpoint tests. The tests should be carried out in order. Installing the Rotunda Transmission Tester allows separation of the vehicle electronics from transmission electronics.
- Bench Testing - Engine OFF
- Resistance/Continuity Tests
- Solenoid Voltage Test
- Dynamic Testing - Engine ON
- EPC Solenoid
- Transmission Engagements
- Upshifts/Downshifts
- Torque Converter Clutch (TCC) Engagement
- Output Shaft Speed (OSS) Sensor
- Turbine Shaft Speed (TSS) Sensor
- Digital Transmission Range (TR) Sensor Testing
- Resistance/Continuity Test
- Sensor Tests
- Switch Tests - PARK/NEUTRAL, Backup lump, and Optional Circuits