Error code P0735 is displayed and the check engine light is on - what does this mean?
DTC P0735 is triggered by the OBD system when the transmission control unit detects a problem with 5th gear in the automatic transmission. This trouble code indicates an incorrect transmission ratio or a faulty function of the fifth gear. For various manufacturers, this error code can also be referred to as "Gear 5 Incorrect Ratio".
What can cause this error code?
- Defective solenoid valves in the transmission control block
- Worn clutches or belts in 5th gear
- Low or contaminated transmission oil level
- Defective speed sensors in the transmission
- Clogged transmission oil filter
- Mechanical wear of the transmission components
- Faulty wiring to the transmission control unit
- Defective transmission control unit (TCM)
- Hydraulic problems in the transmission
What symptoms occur in parallel with fault code P0735?
- Shifting problems: The transmission does not shift into 5th gear or jumps out
- Jerky driving: Uneven running when accelerating or at constant speed
- Increased fuel consumption: Engine runs at higher speeds than normal
- Emergency running program: Transmission gets stuck in the lower gears
- Delayed shifting: Transmission shifts up late or not at all
- Loss of engine power: Reduced acceleration at higher speeds
How can the problem with error code P0735 be rectified?
- Repairing EOBD error code P0735 requires a systematic approach to identify the root cause.
- Change the transmission oil and filter, as contaminated oil is often the cause of shifting problems
- Check the solenoid valves in the transmission control block and have them replaced if defective
- Test the transmission speed sensors and replace defective sensors
- Check the wiring and plug connections to the transmission control unit for damage
- Diagnose transmission control unit and replace or reprogram if necessary
- Measure the hydraulic pressure in the transmission and repair the pump and valves
- Replace clutches and 5th gear bands in the event of mechanical wear
- Carry out a complete transmission overhaul in the event of serious internal damage
FAQ - Frequently asked questions about DTC P0735
Can I continue driving with error code P0735?
It is possible to drive for short periods, but you should avoid high speeds and highway driving. The transmission is running in emergency mode and may suffer further damage. A prompt repair is strongly recommended.
How much does it cost to repair error code P0735?
The costs vary depending on the cause: transmission oil change 150-300€, solenoid valves 400-800€, sensors 200-500€, transmission control unit 800-1500€. A complete transmission overhaul can cost €2000-4000.
How do I diagnose fault code P0735 correctly?
Use a professional OBD diagnostic device, check live data from the transmission sensors, check the transmission oil level and carry out a road test. A specialist workshop should measure the hydraulic pressures.
Is the code P0735 manufacturer-specific?
No, P0735 is a standardized EOBD code that has the same meaning for all manufacturers. However, the specific repair procedures and components may vary depending on the vehicle brand.
What consequential damage can fault code P0735 cause?
Untreated code P0735 can lead to complete transmission damage, overheating, wear of other transmission components and increased repair costs. Timely repair prevents expensive consequential damage.
How long does it take to repair DTC P0735?
Depending on the cause: transmission oil change 2-3 hours, solenoid valves 4-6 hours, sensor replacement 2-4 hours, transmission control unit 3-5 hours. A complete transmission overhaul takes 2-5 working days.