Diagbox 9.91 FAP refill

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mickbaxter31
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Joined: Thu Jun 02, 2022 4:20 pm

Diagbox 9.91 FAP refill

Post by mickbaxter31 »

Hi Guys,
New to this site but from what I have seen very informative, I am struggling with resetting the fluid level on my wife's Citroen's Dispatch Jumpy 1.6HDI 2018 VF7**************[VIN obfuscated, can be read by forum staff] . I refilled the tank a while ago and not sure how but I managed to reset the spanner, I think I went ECU repair and replace FAP tank? anyway the light went out and all good for 3500 miles, now this week the light back on after it was filled and trouble codes P1434 and P1435, I checked the voltage at the FAP and got 9.5v on one pin earth on the other, after looking at loads of info on Google I thought the actual pump must of packed up, Jesus these are costly, I kept going, I was playing with Diagbox and carried out more tests and low and behold the pump started ticking, so its working, the issue I have is even though I have filled the tank reset in every tab on Diagbox I can find, other topics mention resetting to Zero, there is no option on Diag 9.91 I can see, and looking at the level the tank in Parameters its saying only 3% down from 8% earlier today, most likely all the playing around I have done. Can anyone throw any light on where to tell the ECU there is fluid in the tank.

Thanks Mick
wheeler
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Re: Diagbox 9.91 FAP refill

Post by wheeler »

Once in the injection menu go into 'Pack Repair' then replacement parts, there should be various options for replacing things like injectors etc. find refilling the additive tank & follow the on screen instructions.
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GiveMeABreak
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Re: Diagbox 9.91 FAP refill

Post by GiveMeABreak »

You can't really guess at this, you need to perform the correct operation for the job. This has likely caused a knock on issue if the priming has not been completed correctly.

With those fault codes, there are 3 possibilities

1) The fuel additive supply pipe is kinked or damaged, in which case check and resolve
2) The fuel additive supply pipe is kinked or damaged or holed, in which case it needs replacing
3) The third possibility requires a check on the opening pressure of the valve in the fuel tank:
3b) If the opening pressure of the diesel injector is lower than 100 mbar, the fuel tank needs replacing.

Before you have heart failure, I would first try and perform the correct procedure after filling the tank. This involves priming the fuel circuit:

Prime the circuit of the fuel additive pump using Diagbox:- (Repair ↦ Repair pack ↦ Service action ↦ Draining - filling - bleeding ↦ Priming of the additive adding circuit.
N.B. : Follow the entire process. Leave the "ignition positive" until the fuel additive pump stops by itself (Priming in progress).

If you look at the sequence to find the priming operation, you should also see the draining / filling procedure.

So I would attempt the filling procedure first, then the priming procedure (which may be included as part of the filling - I can't say), but if not you now know where to find both hopefully.

With a bit of luck this may fix the issue and because it was not primed after filling the tank it has caused operating problems with the pump.
mickbaxter31
Posts: 3
Joined: Thu Jun 02, 2022 4:20 pm

Re: Diagbox 9.91 FAP refill

Post by mickbaxter31 »

Thanks Marc,
I went through the things step by step but this time no clicking of the pump? I again removed the pump from the tank and gave the pump a feed and it works, I suspect now an intermittent fault on the circuit board (they are the best) as sometimes I can communicate with the Diesel ECU and sometimes not? I have reached out to get a replacement FAP. I still cannot see any settings to tell the ECU by how much that this has been refilled, I go through the steps and all saying good then check the total in the tank and its states just 3% even though I just said I have refilled? PS when you install or say you install a new FAP it goes through all the steps, replace, refill, prime.
You mention kinked pipes, from what I can see it is fine, only I have worked on this vehicle apart from some recalls, and everything looks fine, the pipe is the normal squeeze clip type, just remove and it just sits there, only five nuts and the tank is on the floor, nothing could get damaged unless you maybe do not disconnect and let the tank hang off the additive pipe.
Will let you guys know once I have found the solution.
wheeler
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Joined: Sat Sep 21, 2002 6:07 pm
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Re: Diagbox 9.91 FAP refill

Post by wheeler »

mickbaxter31 wrote:
Fri Jun 03, 2022 1:19 pm
I still cannot see any settings to tell the ECU by how much that this has been refilled
On the later systems like this one you dont tell it an amount, you just tell it that it has been refilled & it will assume it is filled to the maximum. On the older systems you could do partial top ups. They only take just over a litre now.
mickbaxter31
Posts: 3
Joined: Thu Jun 02, 2022 4:20 pm

Re: Diagbox 9.91 FAP refill

Post by mickbaxter31 »

As I said, once this has been resolved I will let you know the outcome. Seems the FAP is at fault and comes as part of the tank, from dealer the price around £250 but on back order with no date. All other outlets the same, only place I can get one is eBay at £935.