Instructions for use / Troubleshooting

Or view a digital instruction book

Instruction book Citroën Instruction book DS Instruction book Peugeot

HD pump location

On all models, the pump is mounted under the oil reservoir at the front right of the engine compartment.
The location of the pump is difficult to access and replacement is therefore time-consuming and expensive. Often the 'not working' of the pump has a cause other than the pump itself. That is why it is important to first make a good diagnosis.
In some cases it is worth removing the right front wheel and wheel well liner to gain better access from the bottom.

Main fuse check / defect

Check the power supply. If the pump does not run, first check the main fuse.

Main fuse 8 (60Ah MF Main Fuse) is located under the BSM at the front left of the engine compartment.

The fuse becomes hot when the pump motor runs continuously. Because the fuse becomes very hot, the inside of the fuse holder melts without this being visible from the outside. The holder melts from the fuse, you no longer have electrical contact while the fuse is still good.

Electrical pump testing

You can test the pump by operating it manually.

  • Disconnect the connector from the ECU.
  • Check whether the power supply (12V) and ground are present.
  • Apply 12V briefly to the control terminal (for example with a 12V probe).
If the pump is now running, it is electrically OK.

Note: Operating 12V for longer than a few seconds can cause damage because it is normally only operated with 5 volts.

The control current comes from the ECU and if there is no voltage on the switching control terminal, the problem is not in the pump.

If the electric motor does not turn, the carbon brushes are often burned or worn.

The pump is placed under the oil reservoir and if oil spills or leaks from the reservoir, it runs directly into the electric motor. You can prevent this by sealing the electric motor.

Car does not rise / Pump keeps running

The pump does not build up pressure and the car does not rise.
Often it is the attachments such as distribution blocks, height sensors and even the power steering that cause the problem. Installing a new pump is then of no use and will quickly break down again. If you do install a new pump and the cause has not been resolved, the new pump will also break.

Note: This is not covered by our warranty.

If the pump continues to run, check that the LDS oil is not being pumped continuously due to internal leakage. This does not keep the pump full for long. Internal leakage mainly occurs at the electrically controlled distribution blocks (front and rear) of the 10mm. piping system.

Control hydro distribution block 10mm. piping system

The car remains in the highest position and does not lower or rise.
Often the cause is the sticking of the solenoid valve in the distribution block. The pump keeps running because the car is not getting to the right level. Check the return line of the pump to see if oil is flowing to the expansion vessel, the pump is functioning properly.

The solution is to operate the electrovalves a few times with the Lexia test box, they will then release and work again. If this does not help, the distribution block at the front or rear may be broken.

Car height problems

Sinks quickly or does not rise (front and/or rear).
Cause: dent(s) in chrome pipes on the HP pump.
You can see this when you remove the ECU from the pump with 4 screws. You now see the 4 chrome pipes. This contains the oil control valves. These pipes are easy to convert, unfortunately they cannot be purchased separately, please contact our sales team to discuss options.

When dismantling: Remember that the spring and the valve come out of the do not jump away.

Height sensor

The height sensors on the front and rear axles may be loose or have shifted. The car sometimes goes up, sometimes not. The pump can also continue to run if the sensor is loose because the car never comes up to level.


To facilitate bleeding the high-pressure pump in the suspension system of the Citroën C5 and C6, we have made an instructional video.

Instructional video (Dutch)

Connect pump with and without extra return

Conversion from pump with extra return to type without extra return. We supply an extra return line for this purpose, which allows you to replace a pump without an extra return connection with a pump with an extra return connection.

Order number: 5270RA

1. Pump without return connection

2. Pump with additional return connection


Note that the hydraulic system works with special LDS oil.

Order number: 1615099680

Not to be confused with LHM or Hydraulic oil. If you use this oil, the system will irreversibly break down.

Flushing hydraulic system

Before installing the new pump it is necessary to replace (flush) the LDS oil several times. A small speck of dirt clogs everything and causes a lot of misery and the cost of a new pump (no warranty). We have repeatedly seen that a worn steering rack contaminated the oil and also caused the pump to fail.

Order number: 1615099680

'Learning' new pump

Learning or programming a used or new pump is difficult and not everyone can do it. This must be done with the original Citroën Lexia test box. If the ECU on the pump is still intact, transfer it. You don't have to teach it.

Copyright @ Bart Ebben B.V. 1978-2023