Citroen C5 Mk II Suspension Will not rise

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white exec
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Re: Citroen C5 Mk II Suspension Will not rise

Post by white exec »

Might be worth checking out the current consumption for the two pumps, as installed.

If current on the suspect pump is not excessive, could also be a poor connection or ground - but I think you might have checked this out already. Clue is the interior light dimming, which suggests an "upstream" poor connection, maybe even right back to fuses or battery connections - somewhere common to both the light and the pump.

Bolted earthing points (engine bay inner wings and footwells) on XM known to deteriorate with age, and respond to cleaning up. Not sure whether C5 might be similar.
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Re: Citroen C5 Mk II Suspension Will not rise

Post by howardaskew »

Latest update.

I have now changed the pump. However it does not communicate properly with the ECU.
I have a Lexia 3.
Does anyone know how to program the new pump ECU?
The Lexia 3 recognises the suspension ECU but I cannot get the pump to operate or actuator to raise front or rear suspension.

The Lexia 3 is an EBay version.

The Pump has an extra rubber pipe connection. I placed a Tee in the return pipe and connected to this extra pump connection on the rear (windscreen) side of the pump.

Changing the motor on a pump looks tricky as their is a connection between the motor and pump that has a rubber band? Maybe impossible?

How easy is it to change the old ECU for the new one?

Many thanks for those who can help.
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Re: Citroen C5 Mk II Suspension Will not rise

Post by cachaciero »

Changing the ECU can't be that difficult because that's what I did on mine, unfortunately it was along time ago and I cannot remember the details.

O.K remembered that I still had the old one so before it goes to the skip I refreshed my memory.
Removing the electronics.
This has to be done with the pump on the bench. With the pump upside down remove the four long Torque X screws one in each corner, the complete electronics assembly can then be lifted of the pump body. On the pump body you will see the armatures for the four electro valves and on the electronics modules the four coils that slide over them. The electronic PCB can be accessed by removing the clip on plastic top but you should not have need to do this.

Removing the motor from the pump.

Remove the two hex head bolts holding the motor end plate on, remove the Torque X screw holding the motor connector block onto the body.. Cut all the silicon rubber away from the connector block and end plate. Lift the end plate off, this will reveal the brush plate, lift this off together with the connector block. Now pull off the main motor stator, this is actually a big permanent magnet and will require a degree of force ! Note ensure that there is no black silicon sealer holding the Stator assembly to the end plate.
You should now have the rotor mounted on the end plate which is bolted with three Torque X screws to the interface / adapter block the adapter block is in turn held to the pump body with a further two screws.
With the pump upside down remove two of the three screws holding the armature bearing plate on to the pump body side of the adaptor slacken the third, you will see a slot, looking into this slot and rotating the pump armature you will see the coupling revolving.
Insert a suitable size jamming bar into the slot thus locking the coupling then rotate the armature anti clockwise this will start to unscrew the motor shaft from the coupling do this for a couple or three turns then slacken the third screw some eventually the motor shaft should be completely unscrewed from the coupling and removing the third screw completely should give you the motor armature and end bearing plate in one hand and the pump assembly in the other as it were.
The coupling is actually a flexible rubber cush drive and the rubber is quite soft so you do not want to stretch it too much, mind I had to destroy one to work out how to remove it but once you can see all the parts all becomes clear :-)

Now as to your problem the motor supply does not come through the ECU it comes directly from the MAXI Fuse to the connector block on the motor. This connector block is more than a connector block it actually contains an electronic switch which is triggered from the BHI ECU. So the first thing you need to check is that you do actually have 12 V to the connector block i.e the MAXI Fuse is good, the next thing that needs to be checked is that the control line from the BHI actually has a signal on it, trouble is at the moment I cannot remember if it is a high or low signal to switch the motor.
As you will have to remove the pump to change the electronics it would be a good idea to check this side of it with the pump loose as it were if my memory serves me it would facilitate access to the connector block, once you have the pump running like that you will know that once it installed and plumbed in it should be good.
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Re: Citroen C5 Mk II Suspension Will not rise

Post by howardaskew »

Latest update.
I was unable to connect with the ECU using my Lexia 3. So I paid for use of the Citroen Lexia 3 software for one week. This was a mistake for the following reasons.
The Lexia 3 software was too up to date and did not cover the C5 Mk 1 or Mk2 like my Lexia 3 does.
It kept coming up with the error "You do not have permissions" to read this model"

I had a "spare pump". I had bought 2 and chose to fit the "wrong one". The fault turned out to be a faulty ECU on the replacement pump. Hence failure to communicate.

I confirmed this by unplugging the Pump ECU and connecting it to the pump we did not fit. Immediately the pump buzzed into life. It started as soon as the door was unlocked.

This proves the power reaches the pump. It does not prove that the 2nd pump with a good ECU has a good pump.
The lesson to learn from this exercise is this.

BEFORE FITTING ANY PUMP CONNECT UP THE ECU AND PUMP MOTOR AND THE PUMP SHOULD RUN. IF IT DOES NOT IT IS EITHER DEFECTIVE MOTOR OR ECU. IT WILL NOT PROVE THE ACTUATOR FUNCTIONS BUT IT WOULD HAVE PICKED UP OUR FAULTY ECU ON THE REPLACEMENT PUMP.

It looks like the official Citroen Lexia 3 is a waste of time and money for cars before the X7.

The Fleabay version of Lexia 3 would operate and test the actuator and pump functions and get the car back up. Its a much better investment of your money.

I used a Gunsons one man bleed kit with a deflated spare tyre to prime the pump when we first removed and replaced the original unit.

I trust this post brings this to an end. I have given up on the repair. My son has sent the car to a garage that will ask for lots of money. We did not fail because of lack of patience on my part. I consider that the garage should fit the 2nd pump and it should work. Providing they check that the pump motor runs before refitting mechanically and refilling with LDS.

Its been a learning curve.

My own C5 Mk1 has covered 174,000 miles without suspension pump attention. My previous model covered 276,000 miles again without suspension pump attention.
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Re: Citroen C5 Mk II Suspension Will not rise

Post by Gibbo2286 »

Changing the motor on the pump isn't too difficult, just undo the screws and pull off the outer body, a strong magnetic force will need to be overcome but that's all, the armature can then be removed by locking the rubber joint (a thin screwdriver pushed through will do) the armature screws off, it's only hand tight.
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Re: Citroen C5 Mk II Suspension Will not rise

Post by howardaskew »

Update July 2016,

The garage would not fit the 2nd hand pump and demanded £1600. My son recovered the car from them and I replaced the pump and ECU. The only alteration was place a T in the pipes as the new pump had a an additional pipe. As soon as it was fitted the car rose nicely. No necessity to bleed or use the Lexia 3. Apologies for not posting this update earlier.
I made the repair in the road opposite a railway station.
The car passed its MOT and is now in regular use.
I would not hesitate to replace a suspension pump without the use of the Lexia 3.
Message to sons out there! Have faith in your old Dad and be patient unless you have the money to sort the problems effectively yourself!
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Stickyfinger
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Re: Citroen C5 Mk II Suspension Will not rise

Post by Stickyfinger »

you are wrong....not more than a couple of bar or the seams can open.
howardaskew
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Re: Citroen C5 Mk II Suspension Will not rise

Post by howardaskew »

?
Stickyfinger what kind of reply is that?
I am reporting the facts from our successful repair.
We never added pressure to the reservoir.
The reservoir only has low pressure pipework so I would not recommend adding pressure to it. Its not designed to take any.
We topped the system up with the car on the stops. We started the engine and almost immediately the car rose.
The pump worked and the hydraulic system must be self bleeding.
Your post is irrelevant and misleading.
Good luck
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Re: Citroen C5 Mk II Suspension Will not rise

Post by GiveMeABreak »

There is a hydraulic system bleeding procedure documented and is recommended to reduce potential problems later on. I'd be happy to send it to you if you let me know which model you have or better still, the VIN.
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Re: Citroen C5 Mk II Suspension Will not rise

Post by howardaskew »

Marc,

The hydraulic system just pushes the air out of its way.
If you read an earlier post I added a slight positive pressure using a one man bleed kit and a flat tyre. I think I was wasting my time. The problem was the pump.
When it was replaced this car just went straight up.
I don't think there are any real differences between the suspension on the Mk1 and the Mk2.
If your pump and ECU are working properly it will just rise.
I wasted time trying to repair the original pump.
Just change it with a second hand unit around £60.
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Re: Citroen C5 Mk II Suspension Will not rise

Post by GiveMeABreak »

It really depends on the problem, but don't forget the newer Mark III X7 (I know you're not referring to this model in particular) has 7 spheres and also supplies the steering rack - so a lot more to be concerned with if you get any air in the system. A lexia can completely depressurise the system in about 3 minutes. But regarding the pump you referred to earlier, there was a modification done for the return pipes where the fluid now returns internally via a duct and not through the pipe - seems you clocked that with the T pipe. The pumps are different too, depending on whether you have Hydractive 3 or 3+ suspension and several other factors - but I'm glad you sorted it anyway.