C4 Cactus hill start faulty

[Citro87]

Hello everyone, maybe someone knows where i can find longitudinal sensor in 2014 diesel cactus automatic? I almost gave up because local dealer has no information where i can locate it and by finding it order a new one. The problem is that car
gave hill start fault and started to jump when brake pedal is released it feels like i'm driving a manual and releasing clutch like newbie. Diagnostic is showing fault C1503 longitudinal sensor faulty. Any ideas?

[Huskyxantia]

Not heard of this , but if it's an electronic thing powered by electricity via battery , I'd check fuses , sorry if you already have.

[Huskyxantia]

This is what artificial intelligence said.
Overview


A "C1503" fault code on a Citroen C4 Cactus typically indicates an issue with the "Eolys" system, which is responsible for adding a fuel additive to help with emissions control; to fix it, you should check the Eolys fluid level, inspect the Eolys additive pipe for damage or leaks, and potentially have the system reset by a qualified mechanic if the problem persists; always consult your car's user manual or a Citroen specialist for accurate diagnosis and repair instructions.

??? Odd.....

[Huskyxantia]

Not sure but this might also be known as a yaw sensor, some older cars used to have this unit under the passenger seat, this might not be the case on your car. Look in the central console area near the hand brake level , so your going to have to work out how the center console is removed ,

[Huskyxantia]

https://www.rexbo.co.uk/car-parts/brake ... -c4-cactus

[RichardW]

I can't see a separate sensor, can only assume it is part of the airbag control unit?

[Citro87]

It is very strange that official dealer from other place somehow found that sensor as a separate part code: 9811627180 and said that it should be somewhere near the handbrake. Everything around it was removed including drivers seat. I also looked under the flooring and the only wires going to the centre of a car are for airbag module, Seat airbag, Seat heating and handbrake switch. Also there is nothing in the front under the panel or near heater core.

[GiveMeABreak]

On some PSA vehicles there is a separate Yaw sensor usually located somewhere in the centre console, but on other vehicles this can be incorporated into the Airbag Control unit ECU, which is why you may not be able to locate it and why the garage may be generalising.....

[RichardW]

That part number is listed for C4 Mk 1 and 2, but not the C4 Cactus.

[GiveMeABreak]

Exactly, so you're looking for something that probably doesn't exist as a separate module on this vehicle.

In my vehicle, the yaw sensor is incorporated into the ESP ECU

[Citro87]

Is there ant way to somehow ensure that airbag module has that sensor intagrated? It has this code on it 9810106480. Of course i can buy a used one for around 50 Euros so it is not expensive, but it will need reprograming.

[GiveMeABreak]

I can't advise, sorry, or like mine, it may be incorporated into the ESP ECU itself....

[Citro87]

As i understand ESP ecu is the one which goes with abs pump. I've spent almost two weeks trying to find what causes that problem and it is very strange that there is almost no information about electric part of that model.

[GiveMeABreak]

Yes, the 'Cactus' model was one of those PSA models that was a bit 'out there' at the time flirting with newer technology before it made its way into different models at a later date, albeit modified. The screens, display, suspension, air bumps etc.

But I don't have the specifics for the ESP setup on the cactus, so can't help you further with this issue, sorry.