OBD-II Generic Error Code P0718: How to Fix It

Q: Can I drive with error code P0718?

It is not recommended. The transmission may shift erratically or go into limp mode, reducing power and potentially causing further damage. Fixed as soon as possible.

Q: What causes an intermittent input speed sensor signal?

Common causes include a faulty sensor, loose or corroded connector, damaged wiring, low transmission fluid, or internal transmission issues. Intermittent faults are often wiring or connection problems.

Q: Do I need to reprogram the PCM after replacing the sensor?

Generally no. Simply clear the code with an OBD2 scanner and test drive. If the code does not return, the repair is complete.

Q: Can a bad input speed sensor damage the transmission?

Yes. If the PCM cannot detect input shaft speed, it may apply incorrect shift pressures, causing slipping, harsh shifts, and premature wear. Prompt repair prevents costly transmission damage.

Q: What is the difference between input and output speed sensors?

The input speed sensor measures the rotational speed of the torque converter turbine (engine side), while the output speed sensor measures the transmission output shaft speed. Both are used by the PCM to determine shift timing and diagnose slippage.

Abstract

Error code P0718 indicates that the transmission's input/turbine speed sensor (sometimes called the 'A' sensor) is sending an intermittent or erratic signal to the powertrain control module (PCM). This can cause harsh shifting, poor acceleration, or limp mode. The fix typically involves inspecting the sensor, wiring, and connector, testing the sensor with a multimeter, and replacing it if faulty.