Error code
OBD2 P0734
OBD2P0734
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.
What it means
Gear 4 Incorrect Ratio.
Severity
moderateCan drive but may experience shifting problems and reduced performance.
Summary
P0734 indicates that the gear ratio for fourth gear in your transmission is incorrect. This issue can affect how smoothly and efficiently your vehicle shifts gears.
Symptoms
- Lack of power
- Transmission slipping
- Harsh or erratic shifting
Common Causes
- Low transmission fluid level
- Dirty transmission fluid
- Wiring issues (corrosion, chafed, melted)
- Transmission speed sensor malfunction
- Corroded connections or pins
Diagnosis
- Check transmission fluid level and condition
- Inspect for leaks or damage to the transmission housing
- Test oil pressure in the transmission
- Check speed sensors and wiring circuits
Fixes
- Replace faulty parts such as sensors, solenoids, or transmission control module if necessary
FAQ
What should I do if my car has P0734?
Start by checking the transmission fluid level and condition. If no issues are found, proceed to inspect wiring and sensors for any damage.
Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.
More OBD2 codes
- P0700Transmission Control System (MIL Request)
- P0701Transmission Control System Range/Performance
- P0702Transmission Control System Electrical
- P0703Brake Switch 'B' Circuit
- P0704Clutch Switch Input Circuit Malfunction
- P0705Transmission Range Sensor Circuit Malfunction (PRNDL Input)
- P0706Transmission Range Sensor Circuit Range/Performance
- P0707Transmission Range Sensor Circuit Low
- P0708Transmission Range Sensor Circuit High
- P0709Transmission Range Sensor Circuit Intermittent
- P0710Transmission Fluid Temperature Sensor 'A' Circuit
- P0711Transmission Fluid Temperature Sensor 'A' Circuit Range/Performance