C0240 code meaning
Brake Pressure Sensor
What C0240 means
C0240 cannot be verified publicly: it is missing from the accessible J2012 lists, from the NHTSA bulletin index, from GM's PIP5094 keyword list and from the Saab and Mitsubishi indexes. Only the part in the title can be described. In a modern brake control unit a pressure sensor reports how hard the driver presses; on the TRW EBC450 of the 2011 Saab 9-5 it is built into the valve block. The module feeds it 5 V and expects about 0 V with the pedal released and more than 1 V when braking. A broken supply or signal line, or a reading that does not fit the deceleration or brake switch, disables ABS, traction and stability control; GM files that fault under C0131. Brake assist and stability control use this signal to judge braking demand.
C0240 at a glance
- Check engine lightUsually not
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyHard
- Typical labor0.5 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of C0240
- ABS, traction and stability warning lamps on
- Brake assist and stability control unavailable
Common causes of C0240
- PossibleOpen or shorted 5 V supply or signal wire to the pressure sensor
- PossibleFaulty pressure sensor inside the hydraulic unit
- Less likelySensor offset not calibrated after module or valve block replacement
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Brake pressure sensorABS hydraulic unitABS control module
What each part of C0240 means
| C | Chassis system: brakes, ABS, steering and suspension. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 40 | The exact fault in that area. |
What to do next
- Note C0240 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about C0240
What does C0240 mean?
C0240 means "Brake Pressure Sensor". C0240 cannot be verified publicly: it is missing from the accessible J2012 lists, from the NHTSA bulletin index, from GM's PIP5094 keyword list and from the Saab and Mitsubishi indexes. It is a generic code, so it means the same on every make.
Is it safe to drive with C0240?
Drive gently and only to a workshop. With C0240 the car can go into limp mode (reduced power) to protect itself.
Will C0240 fail an emissions test?
C0240 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is C0240 to fix?
Difficulty: hard. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will C0240 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.