Fault code C1301 on Peugeot and Citroën: Coherence between brake pedal switch and pressure sensor
What does this fault code mean?
With various brands, but especially cars manufactured by the PSA group (Citroën & Peugeot), we see that the coherence (also referred to as coherence / plausibility) between the brake pedal switch and pressure sensor causes problems. The fault code that can be read here is fault code C1301.
In what vehicles is this fault code commonly found?
Citroën C4 Picasso
This fault code is often read on vehicles equipped with an ATE MK60 and more recent a Bosch 8 ESP.
Symptoms of fault code C1301
An ESP ECU checks the consistency (coherence as it is often referred to by diagnostic equipment) between the brake pedal switch and pressure sensor. This means that as soon as the brake pedal is pressed, the brake pressure in live data should increase and the status of the brake pedal switch should change (from off to on). This adjustment is very accurate. Any deviation in this setting will cause the car to malfunction. In many cases, the ABS light will illuminate.
Causes of fault code C1301
There are basically two reasons that cause fault code C1301 to be triggered on a Peugeot or Citroen: a defect in the brake pedal switch or a defect in the pressure sensor of the ABS unit. Both problems are relatively easy to verify.
Our advice in the case of fault code C1301
To investigate whether the brake pedal switch or the pressure sensor is at fault verify the live data. The brake pedal switch can be checked in live data by determining whether it corresponds to pressing the brake pedal (or not). If not, this indicates a problem with the brake pedal switch.
But beware: there are cases known where it was believed that the brake pedal switch was operating normally as the brake lights illuminated. However, it turned out to be a defective brake pedal switch, so read the data with the diagnostic equipment!
If the brake pedal switch is in operating normally, then it is important to check the pressure sensor. The pressure sensor must be 0 bar in rest position (brake pedal not pressed). When the brake pedal is pressed, the brake pressure should increase and return to 0 bar when released. If not, this might indicate a problem in the pressure sensor. If the car is equipped with the ATE MK60, a remanufacture is possible in 99% of the cases. However, with the Bosch 8 ESP, this problem is often not remanufacturable. To be sure, contact us to verify if the remanufacture of a Bosch 8 ECU is possible. We will be happy to help you.