Hydraulic or Electric Power Steering Pump?

[begins]

Hi all,

Pardon my ignorance.

Do you know whether Citroen uses hydraulic or electric power steering pump in their C5 II (year 2004 ~ 2008)?

If electric power steering pump is used, does it still rely on the shared reservoir with the suspension system?

Kindly advise me.

Thank you very much.

Regards,

[Peter.N.]

The Haynes manual very helpfully says that there are two types used, yes you've guessed it - and mechanical or an electric one. If you look at the auxiliary drive belt you should be able to see it if its mechanical.

Peter

[Clogzz]

The belt-driven hydraulic pump does the steering.
The electric pump does the suspension.
The LDS tank feeds both pumps.

[myglaren]

The belt-driven hydraulic pump does the steering.
The electric pump does the suspension.
The LDS tank feeds both pumps.

There's a suggestion that some but not all more recent C5s have an electric steering pump too.

[Mandrake]

Surely looking up the VIN on service.citroen.com will provide the answer ?

[Clogzz]

The power steering pump for VIN VF7**************[VIN obfuscated, can be read by forum staff] is electric, and it costs thousands.
The part number is 4007 QH.

[Mandrake]

The power steering pump for VIN VF7**************[VIN obfuscated, can be read by forum staff] is electric, and it costs thousands.
The part number is 4007 QH.

Chalk up another one for modern technological "advancement"...

What exactly is the allure of an electric power steering pump ? An electric pump for the suspension I can kind of understand (height corrections when loading a non running car) but you only need steering assistance when the engine is running, so why make it electrical and more prone to fail...(not to mention more expensive apparently)

[RichardW]

It shaves 0.1 MPG off the combined figure, and about the same off the CO2. It probably also saves a few seconds on the build line!

[Gibbo2286]

Probably easier to make variable, computer controlled, light when at low speed, parking etc. heavier at high speed for straight line stability.

[Chris570]

and one less thing to bolt to the engine leaving more room for other addons

[Clogzz]

What exactly is the allure of an electric power steering pump ?

It only pumps when you're steering at low speeds, so it needs sensors and other troublesome frills to find out how you're steering.

The C5's electric suspension pump keeps the car level on the move.
The headlights dim when it switches on, and it also causes the idle speed to drop.
The Xantia doesn't have that problem, the height correctors do the levelling for free.