Technical Comfortmatic - Lack of Hydraulic Pressure

[Ken W]

Hi Fiat Experts,

I have an RHD 2.3L 2018 Ducato that has just clocked 40,000km and I am starting to get low hydraulic pressure error codes and 'Gears Unavailable' messages when all is nicely warmed up after a long drive. I am suspicious that the hydraulic pump motor is failing when it gets hot and I would like to replace it.


Does Anyone Know a Technique for Changing Comfortmatic Hydraulic Pump Motor with the gearbox in situ. I can see part of the back of the motor when I open the bonnet but I can't reach it with my hand. So what do I have to take out from the engine bay so I can reach it, undo the screws without losing them, unhook the electrical connection and put a replacement back in its place?

Cheers Ken

 

[CheeseMonster]

Hi Fiat Experts,

I have an RHD 2.3L 2018 Ducato that has just clocked 40,000km and I am starting to get low hydraulic pressure error codes and 'Gears Unavailable' messages when all is nicely warmed up after a long drive. I am suspicious that the hydraulic pump motor is failing when it gets hot and I would like to replace it.


Does Anyone Know a Technique for Changing Comfortmatic Hydraulic Pump Motor with the gearbox in situ. I can see part of the back of the motor when I open the bonnet but I can't reach it with my hand. So what do I have to take out from the engine bay so I can reach it, undo the screws without losing them, unhook the electrical connection and put a replacement back in its place?

Cheers Ken

Would removing the battery and its box from the cab floor help? I've never looked for the pump and frankly hope I never have too.

 

[MSjoberg]

Hi Fiat Experts,

I have an RHD 2.3L 2018 Ducato that has just clocked 40,000km and I am starting to get low hydraulic pressure error codes and 'Gears Unavailable' messages when all is nicely warmed up after a long drive. I am suspicious that the hydraulic pump motor is failing when it gets hot and I would like to replace it.


Does Anyone Know a Technique for Changing Comfortmatic Hydraulic Pump Motor with the gearbox in situ. I can see part of the back of the motor when I open the bonnet but I can't reach it with my hand. So what do I have to take out from the engine bay so I can reach it, undo the screws without losing them, unhook the electrical connection and put a replacement back in its place?

Cheers Ken

Sorry no, but I know it is possible (but uncomfortable) to remove it from below since others have reported it, at least for LHD. Are you sure it is the pump motor and no other cause, e.g. hydraulic fluid level, pressure accumulator, pump relay, electrical connections?

 

[Ken W]

Thanks for the replies above. I have crawled back in under the front and I can reach in and wrap my hand around the motor and feel one of the domed screws holding the motor onto the pump. I can also feel the electrical connector but I cannot see how to release it so I just gave it a hopeful wiggle. I eyed off the battery box and the top seems to be at about the same level as the comfortmatic system. So I'm sure taking it out will allow me to get both hands onto it but I'm not sure that i will be able to see much of what I am doing. Maybe some lighting and a video camera might help with that.

I also unscrewed the passenger side Headlight so I could get better access to the engine fusebox. I had previously found the relay that switches the motor on and 30 amp safety fuse for the circuit. I tried to replace the fuse, but the FIAT fuse box only allows 17mm long mini blade fuses to go in, not the normal 18.5mm standard ATS units so seeing the fuse looked OK, I put it back in. I also took the 50A Omron relay out and managed to find a 70A unit in the same package type, so I have fitted that. I also managed to attach a wire to the output terminal of the relay and run it out into the vacant section of the positive jump start flap on the fusebox so that next time it fails, I can check the drive voltage going the motor and the motor resistance to chassis. I managed to take the cover off the old relay and I can see some pitting on the contacts from the ~41000 times it has switched the motor on the boost the hydraulic pressure. It is all back together now and as I am still waiting for a new motor to come from Latvia, I will take courage and take it for some short trips around town to see if the issue re-occurs.

Cheers, Ken

 

[NZGrahamO]

Hi Ken

I am also in the process of replacing my Ducato comfortmatic hydraulic pump in place.
Like yourself I hope to replace the pump myself.
Have you done your pump replacement.
If so any ideas on how you went about it.
Tools / time / removal method etc

Cheers
Graham O
NZ

 

[Ken W]

Hi Graham,

I've been under there a few times with tools. I've managed to spray connector cleaner into the power connector and that didn't make it reliable. I can feel one of the torx screws near the engine but I couldn't get a T20 driver or L key onto it - the angle is too difficult. I think you would have to take the bottom and side cover off to get better access.

I don't seem to be able to reach it through the bonnet. You would have to take all the air pipes and flow sensors out to get room and then you might get line of sight to the screws and get tools onto them using extensions. The top of the motor is very close to a metal air pipe that bolted to the turbo or inlet manifold.

A replacement motor (it seems to be a brushless DC motor judging by the way if cogs when you turn the spindle) comes with 3 new screws and a new transmission plate that fits between the motor drive and hydraulic pump so there are spare screws if you lose any. The motor has a bearing on the end shaft that fits into the pump housing so it needs some clearance above the motor to get it inserted and to get the slots on the transmission plate locked into both motor and pump.

I've chickened out and found a FIAT Service Centre who will do the job at a not completely unreasonable price and it is booked in there early next Tuesday. I'm just hopeing I don't need a flat top truck to get it there. I'll post again after this exercise is completed hopefully successfully with any new info I have gained.

Cheers, Ken

 

[NZGrahamO]

Hi Ken

Thanks for your reply.
Can you tell me approx hours / price the Fiat dealer thinks it we take to do the replacement jwork.
Are you in the UK / Europe.

Cheers
Graham O