In limp mode, transmission may be limited to second or third gear, or it may be locked in "park" or "neutral." The check engine light will usually come on, and the transmission may display a trouble code.
There are a number of things that can cause a transmission to get stuck in limp mode, including:
- Low transmission fluid: This is the most common cause of limp mode. When the transmission fluid is low, it can't properly lubricate the transmission components, which can cause them to overheat and fail.
- Dirty transmission fluid: Dirty transmission fluid can also cause the transmission to get stuck in limp mode. Dirt and debris can clog the transmission's filters and passages, which can restrict the flow of fluid and cause the transmission to overheat.
- Failed transmission solenoids: Transmission solenoids are responsible for controlling the flow of fluid in the transmission. If a solenoid fails, it can cause the transmission to shift gears erratically or get stuck in limp mode.
- Faulty transmission sensors: Transmission sensors monitor the transmission's speed, temperature, and pressure. If a sensor fails, it can send false information to the transmission control unit (TCU), which can cause the transmission to get stuck in limp mode.
- Mechanical damage: Mechanical damage to the transmission, such as a broken gear or shaft, can also cause the transmission to get stuck in limp mode.
