C5 suspension pump/ ecu

[Lighty]

Not sure if any of you can point out my mistake, fitted a used one of these today (new one is over £600). I have changed 3 or 4 of them before, but this one will not pump the car up.
The origional needed a wack to make it work.I have configured it in almost every option, the car is an exclusive, so is hydractive, with xenons, and no steering angle sensor.I have selected every choice just so see if it would work. i have carried out the steering angle sensor configuration, that it says to do when changing the ecu, and it says that is ok.
the pump makes a noise, but doesnt sound as if it is actually moving fluid, IE not under load. I realise the used unit could be faulty, but can anyone think of something I have missed .
I am sure on the last ones I did, they were quite straight forward.

[myglaren]

Does it need priming?

[Lighty]

Could be, perhaps it will work in the morning after a night left to settle, otherwise I can try slackening the pipes to let it run through.

[Gibbo2286]

You need to raise the pressure in the reservoir to bleed these pumps, you can do it by using a bicycle pump with a suitable home made adapter, it only needs about 5 psi.

[Lighty]

You need to raise the pressure in the reservoir to bleed these pumps, you can do it by using a bicycle pump with a suitable home made adapter, it only needs about 5 psi.

Never knew that , will give it a try, I have a cooling system tester, I bet one of the caps will screw on and I can pressure it up a bit , Thanks for that.

[Lighty]

Well guys, the pressure method seemed to do the trick, I used the Mitty Vac on the return pipe to the tank, 5 psi and the noise changed. Still wouldnt come up for ages, but after about 10 turn off of the engine and restart, she came into life, so I am sure the pressure helped, must have been lucky last time. Big thanks