C5 2.0 hdi 55 reg power steering problem

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mark230678
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Re: C5 2.0 hdi 55 reg power steering problem

Post by mark230678 » 02 Oct 2018, 19:30

You read it spot on.
Amazed it took a litre.
And it was level on low setting.
Another look in the morning

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Re: C5 2.0 hdi 55 reg power steering problem

Post by mark230678 » 03 Oct 2018, 14:45

So the sponge around the pump is saturated.
Can't see any obvious leaks yet.
Took another 1/2 litre to fill though

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GiveMeABreak
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Re: C5 2.0 hdi 55 reg power steering problem

Post by GiveMeABreak » 03 Oct 2018, 16:21

Ok, I would have a look at the LDS tank. These tended to split under pressure at the seams. This was caused by hydraulic cars like the C5 and C6 up on a ramp with the wheels hanging free and unsupported, without first raising the suspension on high and undoing the LDS tank cap. As a result, the weight of the wheels creates uncontrolled pressure in the system, and when it is lowered the pressure can force back through the system and burst or weaken the hydraulic tank.

Even though a vented cap was later fitted, these are insufficient to handle the pressure under the circumstances I described. So check the tank near or around the seam.

If it is not leaking down from the tank, but is coming from the pump, it may be a loose hydraulic union connection, or a leak int he pump itself, if you have ruled out other areas or rusted hydraulic pipes in the area.

Some photos may be helpful (they can be uploaded directly to the forum when using the full editor option.

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Re: C5 2.0 hdi 55 reg power steering problem

Post by mark230678 » 03 Oct 2018, 17:26

Yeah. Not great with pics.
The sponge was only soaked at the bottom half.

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Re: C5 2.0 hdi 55 reg power steering problem

Post by GiveMeABreak » 03 Oct 2018, 17:51

Ok, here's a cross-section of the LDS tank. The parts I've marked in green are referenced in the table and show whether outward or return line of the hydraulic fluid. The parts I've arrowed in red show the seam and this is where it can become weakened over time if the correct lifting procedure is not followed whenever the vehicle will be lifted with wheels hanging freely.
C5 MK II LDS Tank X Section.PNG
ReferenceFunctionComponent
"a"ReturnSuspension Struts
"b"Suction lineIntegrated BHI (BHI)
Power Steering Pump
"c"ReturnIntegrated BHI (BHI)
"d"ReturnPower Steering Pump

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Re: C5 2.0 hdi 55 reg power steering problem

Post by mark230678 » 03 Oct 2018, 18:01

Codes still remain.
On the codes when read it does say the pump isn't turning.
Also got 0601 off the ecu.
Tank looks dry.

Doing my head in.
Did change a drop link as well. Don't get me started on that.
Attachments
20181003_173920.jpg
20181001_140732.jpg
20181001_140658.jpg

mark230678
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Re: C5 2.0 hdi 55 reg power steering problem

Post by mark230678 » 03 Oct 2018, 18:06

Struts are dry.
Road was dry this am.
Little moist at the rears. But only moist.
Rack seems ok.
Had it running all afternoon.
Lock from left to right as many times as I could.
No drips or drops

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Re: C5 2.0 hdi 55 reg power steering problem

Post by GiveMeABreak » 03 Oct 2018, 18:20

Ok, slightly worrying looking at those screenshots:

P0601 is basically an ECU fault - either the EEPROM has failed or it cannot read the fault codes stored in the ECU - and in this case it is the Power Steering ECU - so it cannot tell us the specific fault codes stored within it.

On the P0602, this tells us that there has been a downloading error to the ECU - now that is the concerning one as this should only occur if the ECU has had to have it's software updated or the configuration has failed during a telecoding session and the data has not been written back to the ECU properly - in other words it has become corrupt. I have to ask whether you have tried to use any 'automatic configuration options? Never advised with a clone unit.

I would check the connections to the power steering pump - clean the connectors and check the pins. So you have 2 faults - a leak and a communication issue with the power steering pump ECU.

I can only suggest at this point that you try and get it to a dealer and make them aware of the fault codes you have (keep the printouts or screen shots) and see if they can A) determine if the ECU has in internal fault - they may be able to download the software to it again if they can communicate with it - and they may be able to assist with the leak.

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Re: C5 2.0 hdi 55 reg power steering problem

Post by mark230678 » 03 Oct 2018, 18:25

Definitely not done any automatic settings. Wouldn't know how.
The faults were on one day when I came back to it.
Only just got lexia working a few days ago.

If I recall when doing the power steering codes. It can't recognise it properly.

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Re: C5 2.0 hdi 55 reg power steering problem

Post by MikeT » 03 Oct 2018, 18:52

I would make power connections my priority, 6volts is a big red flag.

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Re: C5 2.0 hdi 55 reg power steering problem

Post by GiveMeABreak » 03 Oct 2018, 19:08

Yes, that's what I meant above really - the diagnostic is unable to communicate with the ECU. Until you get the leak sorted, it will be permanently losing fluid and that stuff is not cheap - Once the leak is sorted then you can focus on the pump.

As far as the Power Steering pump itself goes, here are the components and the electrical connections, should you want to test them. Are you getting any power assistance from the steering?
C5 MK II Power Steering Internals.PNG
C5 MK II Power Steering Internals BN.PNG
(4): Electropump support
(5): Hydraulic fluid reservoir
(6): Manifold
(7): Connectors
(8): Acoustic soundproofing half-cowling
(9): Connector protective cover
(10): Connector protector fixing plate
(11): Electric motor
(12): Electropump assembly ECU (2 electronic cards and 2 temperature sensors)
(13): Electropump assembly filter elements
Power connector " a" :
Terminal 1 : + 12 V
Terminal 2 : Earth
Connector "b" :
Terminal 1 : CAN
Terminal 2 : CAN
Terminal 3 : NC
Terminal 4 : CAN
Terminal 5 : CAN
Terminal 6 : NC
Terminal 7 : Ignition+
Terminal 8 : Line
Terminal 9 : NC

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Re: C5 2.0 hdi 55 reg power steering problem

Post by GiveMeABreak » 03 Oct 2018, 19:19

Yes, well spotted Mike, the voltage for the power steering at normal operation should be 13.5V - The Power Steering has a small reservoir of LDS fluid within the pump. If there is a failure in the electronic cards in the pump (ECU) it goes into backup mode to provide some assistance.

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Re: C5 2.0 hdi 55 reg power steering problem

Post by mark230678 » 03 Oct 2018, 22:24

Ok.

The steering is absolutely fine.
No problems at all.
Other than the stop light.
And message on display.

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Re: C5 2.0 hdi 55 reg power steering problem

Post by mark230678 » 06 Oct 2018, 17:25

Back to this again whilst looking at the front.

Connector a) in the above diagram.
Only has one wire.
Purple.

Right or wrong.
Looked at everything.
Took all off and cleaned and put back on.
Just need to read code to see if it will delete now.

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Re: C5 2.0 hdi 55 reg power steering problem

Post by GiveMeABreak » 06 Oct 2018, 19:13

It shouldn't work with only one wire - it will need both to make the circuit work. Are you saying both pins are there, but one of the wires has been pulled out?