Transmission
P0700 — Transmission Control System (MIL Request)
The transmission control module (TCM) has stored a fault and asked the engine ECU to turn on the check engine light. P0700 is only a pointer: the real fault is in the TCM's own codes.
Common causes
- Any fault stored in the transmission control module
- Faulty transmission speed or pressure sensor
- Faulty shift or pressure solenoid
- Wiring or connector problem
- Low or dirty transmission fluid
Symptoms
- Check engine light
- Harsh, delayed or missing shifts
- Transmission in limp mode (fixed gear)
- Gearbox warning light
How to check
- Read the codes from the transmission control module, not just the engine ECU
- Check the transmission fluid level and condition
- Check sensors, solenoids and wiring named in the TCM codes
- Fix the TCM codes first, then clear P0700
Can you keep driving?
Drive only to a workshop. A transmission in limp mode or with harsh shifts can be damaged by continued use.
Related codes
Frequently asked questions
- What does P0700 mean?
- The transmission control module has a fault and asked the engine ECU to turn on the warning light.
- How do I find the real fault behind P0700?
- Scan the transmission control module for its own codes; they identify the actual problem.
General reference information. It does not replace a diagnosis on your own vehicle. The same code can have different causes depending on make, model year and engine; check the manufacturer's documentation or ask a technician with a scan tool.