C4 Picasso (B78) 2014 Gearbox Actuator oil leak

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danlat1415
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C4 Picasso (B78) 2014 Gearbox Actuator oil leak

Post by danlat1415 »

I have a 2014 Citroen C4 Picasso (5 seater).
It's an automated manual transmission.

I had removed the engine undertray because I was replacing it as the old one was split and hanging off.
I noticed a large oil patch on the left side of the vehicle (opposite side to the engine oil).

I looked in the engine bay and saw some kind of leak all over the top of the gearbox actuator reservoir.

I suspect it may be the high pressure hose.
PXL-20220723-144017681.jpg

Can anyone tell me how to remove the hose (both ends), as the upper end is difficult to access, and the lower end doesn't move at all by hand. Do I need any special tools?

It's part number 2 in this diagram;
00061546.jpg
Is this something I can replace myself, or is this a garage only repair?

The part number for the hose is - 2090 38
My VIN is - VF7**************[VIN obfuscated, can be read by forum staff]


As there has been a leak, I will need to replace any lost fluid (seems to have been quite a lot over time).
Is it transmission oil, or a special actuator oil?
Also, how do I refill (through the reservoir cap?) And how much do I fill? Is there a max/minimum?


Thank you
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GiveMeABreak
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Re: C4 Picasso (B78) 2014 Gearbox Actuator oil leak

Post by GiveMeABreak »

It's a special oil not transmission oil and to top up the system it MUST be depressurised first.

SELENIA oil
TUTELA CAR CS SPEED
SAE 75W (Part number 9979.A4)

The fluid level is then topped up to the marks in the reservoir, then the system is repressurised using Diagbox.
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Re: C4 Picasso (B78) 2014 Gearbox Actuator oil leak

Post by danlat1415 »

Thanks very much for your quick reply.

That's frustrating, as it will be a dealer repair.
Do you know roughly how much it it may be?

From what I can gather, the hose is approx £30-40 and the special oil is also £30-40.
Is there a service guide for the repair, listing an approximate repair time?
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Paul-R
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Re: C4 Picasso (B78) 2014 Gearbox Actuator oil leak

Post by Paul-R »

I would have thought that an independent garage with a high-end code reader (Snap-On, Autel, etc.) would be able depressurise/repressurise the system as well. And for a much better price than a dealer!
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Re: C4 Picasso (B78) 2014 Gearbox Actuator oil leak

Post by danlat1415 »

I have Diagbox and have used it a few times before.

Is this something I could do in full myself, or is it a garage only repair?




Also, I don't know how long this has been leaking, I haven't noticed it until recently.
It's it possible it's been caused by the extreme heatwave in the last few weeks? It's been 40 degrees where I am (normally 10-20 degrees)
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Re: C4 Picasso (B78) 2014 Gearbox Actuator oil leak

Post by GiveMeABreak »

The depressurisation I can help you with:

Fluid level
N.B. : The oil level is checked after depressurising the piloting actuator.

Connect the diagnostic equipment to the vehicle’s diagnostic socket.
Switch on the ignition.

Select from the diagnostic tool menus:
The vehicle
The RPO n (Diagbox probably not ask for this).

Perform the global test.

Select and validate the menus:
  • Gearbox ECU
  • Specific operations
  • Check of the gearbox piloting actuator oil level
The diagnostic tool displays a new menu.

Select: Depressurisation of the hydraulic circuit.

Check the level of oil contained in the piloting actuator hydraulic reservoir.
The oil level must be at maximum ( as "a").
Carry out:
  • Top up with oil if necessary
  • Pressurise and bleed the hydraulic circuit
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Re: C4 Picasso (B78) 2014 Gearbox Actuator oil leak

Post by danlat1415 »

Thanks.
I will probably top up the oil level whilst I look into it more regarding changing the pipe.

On Diagbox, is there an option to pressurise the system again?
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Re: C4 Picasso (B78) 2014 Gearbox Actuator oil leak

Post by GiveMeABreak »

Yes, it should also be in the same section as I described above.
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Re: C4 Picasso (B78) 2014 Gearbox Actuator oil leak

Post by taffy »

I've just changed clutch etc cleaned all up and it's weeping oil,I'm suspecting the cap as return ok etc can u get a new one?
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Re: C4 Picasso (B78) 2014 Gearbox Actuator oil leak

Post by danlat1415 »

taffy wrote:
30 Jul 2022, 11:33
I've just changed clutch etc cleaned all up and it's weeping oil,I'm suspecting the cap as return ok etc can u get a new one?
The reservoir cap is sold separately.
Part number - "2088 39"
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Re: C4 Picasso (B78) 2014 Gearbox Actuator oil leak

Post by danlat1415 »

I finally got got some actuator oil 9979.A4 and a new hose.

I've connected the car to Diagbox (Diagbox 7.66 as that works best for my vehicle) and tried to follow your instructions for depressurising the system, but I can't find any option for it.

I've run a global test, then gone into the Gearbox ECU that shows up in the global test results (no errors listed).

I get the following options list;
- identification
- fault reading
- standard parameter measurement
- personalised parameter measurements
- actuator test
- repair


I have been into all of those screens and I can't find anything similar to your instructions;

Gearbox ECU
Specific operations
Check of the gearbox piloting actuator oil level
The diagnostic tool displays a new menu.
Select: Depressurisation of the hydraulic circuit

Please can you help??
The Gearbox ECU is showing up as CFC300P
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GiveMeABreak
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Re: C4 Picasso (B78) 2014 Gearbox Actuator oil leak

Post by GiveMeABreak »

Go into the repair menu. You should find options there.

The problem is the Menus do change with each version of the software, So it won’t necessarily be exactly as it was listed a few years ago. But do have a look around the menu and find something to do with the gearbox actuator. The options will probably be in there somewhere.
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Re: C4 Picasso (B78) 2014 Gearbox Actuator oil leak

Post by danlat1415 »

Thanks for the guidance.
It's heavy raining now so I can't retry, and I won't get chance until weekend.
I'll update the thread when I do, if I find the correct options.
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Re: C4 Picasso (B78) 2014 Gearbox Actuator oil leak

Post by danlat1415 »

To update the thread;


I managed to find the Diagbox options for depressurising and repressurise the gearbox actuator;

- Global Test
- go into the Gearbox ECU
- Repair
- Pack Repair
- Replacement Parts
- Check the gearbox control actuator oil level
- Depressurisation of the hydraulic circuit


To repressurise, it's exactly the same procedure, but instead of Depressurisation, select Pressurise the Hydraulic Circuit (which is the option just below depressurise).



So despite being able to find the options, I ran them, but it said 'action terminated'?
For both depressurise and repressurise...

I don't know if it actually did anything or not, but as I was ready to get the job done, I went ahead with replacing the pipe and topping up the reservoir anyway, however the reservoir was already almost full.

So now I'm thinking that it may not have been an actuator oil leak (despite my photo in first post).
I'm thinking it may be a brake fluid/clutch fluid leak from somewhere. Or maybe even a gearbox oil leak.

I'm not getting any warning on my dash, and Diagbox doesn't find any error codes - but there is some kid of leak somewhere as I had a large patch on my undertray, and the actuator reservoir is visibly oily on the outside.


So I'm still hunting.