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Discussion Starter #1
My brothers 147 has just developed a problem. It was driving beautifully when all of a sudden it started going into neutral by itself and also not selecting the correct gear. He stopped into a local alfa garage and they told him you need a new actuator.

Anyway i hooked up Alfadiag and read the fault code - P1769 Diagnose Pump Relay Stuck.

I can clear the code but as soon as the pump kicks in to bring the pressure up the error code comes back again. I checked the circuit pressure and it is correct, no less than 45 BAR before the pump kicks and then it goes to about 75 BAR.

There are two 50A relays under the hood, one next to the large selespeed plug on the left side of the battery and one in the fuse box in front of the battery, but according to the diagram it is meant to be for the fan. I have tried swapping them around but with no luck, the same problem.

Another thing i found is when i go to 'electrovalve odd gears' or 'even gears' the hydraulic pressure completely drops away almost to zero. I noticed this because it didn't make barely any sound after the first attemp (as it makes 5 attemps in a test). as soon as you test the pump though, the pressure shoots back up to where it should be.

I also found that i cannot run the 'Auto EV Adjust/Service' calibration routine as it results in error.

Any help or suggestions would be much appreciated, thanks in advance!
 

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I was going to suggest swapping the relays!

The pressure is getting too high. Normal pressure should be in the range 45-55bar, so it sounds like the pump relay is sticking on, rather than not running the pump.

Might be worth sourcing a 3rd relay to see if that cures it. You can find them on any 147/156 etc. As you say, it's the fan relay.

The garage is telling you a very expensive lie. Avoid!
 

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Discussion Starter #3
so the other 50A relay next to the big plug is for the selespeed control unit? and the actual pump relay is the one in the fuse box marked as fan.

actually would it be possible to bridge the control unit one since it stays on all the time, and use that relay for the pump?
 

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The accumulator on your actuator has a split diaphragm and requires replacement- source either 2nd hand from an alfa actuator or buy new -Fiat Stilo Abarth or similar. The garage is not lying by saying the actuator needs replacement as a new actuator will replace the faulty accumulator- but the accumulator can be changed alone (assuming the remainder of the actuator is good) and save some money. Your Sspeed oil maybe slightly low as a bubble of nitrogen gas has escaped from the system.
 

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...another garage actuator replacement dream :rolleyes:
 

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Discussion Starter #7
The accumulator on your actuator has a split diaphragm and requires replacement- source either 2nd hand from an alfa actuator or buy new -Fiat Stilo Abarth or similar. The garage is not lying by saying the actuator needs replacement as a new actuator will replace the faulty accumulator- but the accumulator can be changed alone (assuming the remainder of the actuator is good) and save some money. Your Sspeed oil maybe slightly low as a bubble of nitrogen gas has escaped from the system.
you sound 100% confident that this is the problem... how so?
 

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so the other 50A relay next to the big plug is for the selespeed control unit? and the actual pump relay is the one in the fuse box marked as fan.

actually would it be possible to bridge the control unit one since it stays on all the time, and use that relay for the pump?
That's the pump relay, I'm pretty sure. The one in front of the fusebox is the fan, but the 2 relays are interchangable.
 

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Discussion Starter #9
well i've read different things... some people say that the 50A one in the fuse box marked as 'fan' is actually the pump relay.

i swapped this relay with the one next to the big selespeed plug on the side of the battery to no effect.
 

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This error is indicates a split diaphragm as the Sspeed pump has to run nearly constantly to sustain pressure. The accumulator "stores hydraulic pressure" if you like and you should check to see wether you have lost a little Sspeed oil from the resevoir since problems have started (assuming there are no other leaks). A simple test: Ign on let pump prime, and should go quiet when upper pressure achieved. Foot on brake make a few up shifts to consume hydraulic pressure, it should make at least 3 gear changes before the pump cuts in again. Have a look on the net about accumulators- these are similar to those found in Citroen / Bentley suspension etc. and when these pop internally the suspension goes rock hard because the air is used as a spring. Furthermore I speak from experience- they are not difficult to change, battery tray out and 27mm spanner, make sure you depressurise first. If you have access to spares it can be swapped over quickly to confirm your diagnosis.
 

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Discussion Starter #11
when i turn the IGN on, the pressuree goes to about 75 BAR... after 20-30 seconds it drops to 45 BAR and the pump kicks in again and then shoots to 75 BAR again. every time the the pump kicks in the error code "pump relay stuck" is produced.

how long should the pressure be maintained in the system before the pump kicks in usually? there are no leaks as far as i can tell.

i have no problem changing the accumulator, i can buy them locally brand new fairly cheap.
 

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CrackleBlack is right: your accumulator has failed. I have seen this several times.
Pressure should never exceed 55 bar, and should be maintained for several minutes, though the time depends on the age/condition of the actuator.
The garage was not being dishonest by quoting for an actuator; the accumulator is not available as a separate part from Alfa.
 

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Discussion Starter #13
problem solve - it was the accumulator!

thanks for the help guys! once i found that the pressure was not holding in the system as soon as a gear was selected confirmed it for me.
 

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The garage was not being dishonest by quoting for an actuator; the accumulator is not available as a separate part from Alfa.
while that is true, the part is available from a Fiat dealer for about £60, a helpful dealer shouild know that

part No 71751195

EB spares stock it as well apparentley according to the selespeed info sticky

HTH
 

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Can anyone post a pic of the location of it, as I'm sure i have the same issues, then i think ill need a re config as well
 

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it sits on top of the actuator, a spherical thing...it is the same (but smaller) as the accumulator of your heating system in the house (providing you have central heating)
 
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