Fault codeP0988

MODERATE

Transmission Fluid Pressure Sensor/Switch E Circuit Range/Performance

What this code means

Transmission Fluid Pressure Sensor/Switch E Circuit Range/Performance.

P0988 is a generic code: it means the same thing on every make. P0988 belongs to family P09xx — Transmission and controls. Its page explains how to read a code and groups all its codes by part.

Type of fault

The signal stays within its electrical limits, but its value is not plausible: it does not match what the control unit expects given the other sensors. The sensor may be drifting with age, but it may also be faithfully measuring a real mechanical problem — a leak, a blockage, an air leak. Replacing the sensor without checking does not always clear the fault.

Gearbox hydraulic pressure

Automatic, dual-clutch and automated gearboxes work with hydraulic pressure, produced by a pump and measured by pressure sensors or switches. The control unit checks that the pressure follows what it commands.

What you notice

Harsh or slipping shifts, a gearbox that will not engage, a limp mode with a single gear.

How to check it

Check the fluid level and condition first. Then the connector and wiring of the sensor or switch. A pressure that is really too low points to the pump, a filter or an internal leak, a job for a gearbox specialist.

What to do

Have it checked this week. The car remains usable, but the fault will not clear itself and will fail the roadworthiness test.

Clearing a code switches the light off but repairs nothing: if the fault remains, the code comes back. Clearing a fault code yourself →

How to read this code

PPowertrain
0standardised code
9Transmission and controls
88P0988