P1700 – Transmission Control System Malfunction (Toyota)
Description
The ECM detected a malfunction in the transmission control system affecting shift quality and drivability.
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View Recommended ScannersSymptoms
- Harsh shifting
- Delayed shifting
- Failsafe mode
- Poor acceleration
- Check engine light
Causes
- Faulty TCM
- Wiring issues
- Low ATF level
- Valve body malfunction
- Sensor faults
Diagnosis
- Check ATF level
- Inspect wiring
- Scan TCM data
- Test sensors
- Inspect valve body
Repair
- Refill ATF
- Repair wiring
- Replace sensors
- Service valve body
- Replace TCM if needed
