Citroen c5 2.2 x7 -13 stuck in lowest

[Bils]

Recently bought a Citroen c5 c7 2.2 that won’t raise the front suspension. The rear works fine in all height settings. I’ve changed the height sensor but it didn’t change anything. I’ve also charged the battery since it was in economy mode. Anyone has an idea ?

The codes I get is:
C1147 rear body height sensor fault
U1118 Fault absence of communication with built-in-systems interface
U2118 Triggering height adjustment receipt anomaly

[mickthemaverick]

Have a read through this thread, you may get some ideas.

[Kees]

9 out of 10, the lever of the height sensor is in the wrong position!!
Look at the position it is now, then you can turn it 90 degrees up or down, depends how it's now and reconnect the rod.
This fault happens when the lower arm is replaced or other repair on it.
Because the height sensor is connected to the stabilizer rod, the position of the lever is changed without noticing.

[Bils]

Nothing is happening with the lever on the height sensor, I’ve hade the dog bone off and gently turned the lever and you can hear the hydraulic pump trying to raise the car but it won’t move

[Kees]

Normally it take some time to gif the front to react.
But if the pomp is running and nothing happens, then it's possible, that the valves in the BHI are broken.

[Bils]

I removed the bhi and the valves looked fine(as did the motor). The rear raised as usual after I bleed the system. There are pressure out from the pump in the hydraulic lines. I cleared the codes and none have come back but it still won’t raise the front. I’m beginning to suspect the front regulator sphere. Are there any electric valves there ?

[Kees]

No, there is no such thing! What you mean is the stiffness regulator, and yes there's a electric valve, but this only shut off the sphere, when this one is not energized with 12V the sphere is connected with the system.
There's also a return line to the lds tank, the same as on the back hydraulic unit.

[Kees]

There's also another possibility, I remember the same question in the past, in this case the pomp unit with BHI was replaced with one from different type C5.

[Bils]

Do you think that the stiffness regulator could affect the ride height? . I activate sport mode and did not notice any difference in the stiffness on the rear suspension.

[Kees]

This is a common mistake!! The difference between these two is done with the parameters in the software, i mean for example if you ride on a flat road you don't feel any different between soft/stif.
When we change the road with some holes/bumps, you notice that the suspension will change sooner to stiff then the soft mode, but again, this depends on the threshold parameters.

[Bils]

But could it affect the ride height, it feels like it’s not getting pressure out to the front suspension. The pump is constantly trying to raise the suspension.

[Kees]

No, i don't think so.
Look at the error U2118, this means the value of the height sensor is out of range, this is also the reason why the pomp is working.
Maybe you should check the voltage on the height sensor itself, pin #1 5v, 2 signal between 0.3 and >4v and #3 massa (0v).
Maybe there's something wrong with wiring.
This is also, why i said in the beginning, check the position of the lever on the sensor, because if it is in the wrong position, the value to the BHI is wrong.