Citroen Grand C4 Picasso 2012 MCP6 error

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kalm007
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Joined: 25 Oct 2023, 21:14

Citroen Grand C4 Picasso 2012 MCP6 error

Post by kalm007 »

Hi everybody!

I have a problem with my car. I received an error code. P0944. I have deleted the error code for two weeks and I tested the mcp6 with diagbox. All test was good so I do not know what the problem is :( I looked at the oil pressure value and it was 40-45 bar. Sometimes it was 50 bar in operating process I used my car and I drived 200-300 km without problem. Now I received the error code again. I looked at the oil level and it is good as well.
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GiveMeABreak
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Re: Citroen Grand C4 Picasso 2012 MCP6 error

Post by GiveMeABreak »

It's saying there isn't enough pressure in the accumulator that provides the high pressure required to operate the system.

Fault Code: P0944
Description of Fault: Fault: oil pressure storage cell discharged: Not characterised. Discharging of the hydraulic accumulator.

The following conditions have to be met:
- Clutch closed
- Absence of gear changing

Technical precision on the context of appearance of the fault code:
  • Operation of the hydraulic pump.
  • Supply voltage correct between 8V and 16V (Pin 3 of the 28-way connector)
Conditions for Fault to clear: Ignition switched off and on again
Downgrade Modes whilst Fault is active: Change to Neutral and anticipated closing of the clutch ( engine running - Gear engaged - Clutch open)
Symptoms:
  • Lack of power
  • Leaks
Suspect Areas:
  • Electric motor
  • Electro-pump
  • Level of oil in the gearbox hydraulic reservoir
  • Accumulator
  • Pressure sensor
  • Leak/kinking in the hydraulic piping
  • Controlled manual gearbox ECU
kalm007
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Joined: 25 Oct 2023, 21:14

Re: Citroen Grand C4 Picasso 2012 MCP6 error

Post by kalm007 »

Thank you for your help.
I didn't understand why i didn't get a notificaton that i got a help. :S

So the main problem is the electric pump. Firstly I have to replace it.

https://eurofrance24.com/catalogsearch/result/?q=259150
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GiveMeABreak
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Re: Citroen Grand C4 Picasso 2012 MCP6 error

Post by GiveMeABreak »

You need to check your user preferences under your profile to ensure you are notified accordingly.
kalm007
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Joined: 25 Oct 2023, 21:14

Re: Citroen Grand C4 Picasso 2012 MCP6 error

Post by kalm007 »

myglaren admin helped me in private message and it is working. :)

So currently I use my car and when I drive it sometimes I get an error message on the display. " gearbox faulty" but I can drive it. But sometimes the the transmission ( "when I am driving" ) change to neutral . So I have to set from A to N and from N to A and I continue drive.

Do you think the oil pump could be bad what I linked former.
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GiveMeABreak
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Re: Citroen Grand C4 Picasso 2012 MCP6 error

Post by GiveMeABreak »

It's not going to get any better, that's for sure, so I would get it seen to by a competent garage that has a lot of experience with these piloted manual boxes - or get it to a good dealer as it may save you money in the long run if they can diagnose the problem straight away. AS you can see the fault descriptor has multiple possibilities, so you really need it confirming first before replacing parts.
kalm007
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Re: Citroen Grand C4 Picasso 2012 MCP6 error

Post by kalm007 »

Yes. But it is very expensive :(
Today I made some test with diagbox. Firstly I got a new error code. P0868. Too low pressure. I searched this error code on the internet and I found a russian video. He had this problem. He disassembled the control unit and he replace the actuator accumulator and the problem was solved. I think I try this method.

Sorry it is contain hungarian language. Hidraulika nyomás= Hidraulic pressure.

Continuously it is losing the pressure and the actuator motor working when the pressure is too low. The actuator motor make a normal pressure and right after the pressure fall slowly when the pressure is good.

You can see this process on the picture.
IMG_20231109_163130.jpg