Eberspacher b3l pump not clicking (read on....)

[steve66]

Hi.

I have an issue with my eberspacher b3l which I bought for my Devon. I have the whole setup, all sensors are working fine when I checked resistance etc. but, when I try to fire her up the fan runs, spark is there, nice and strong and the glowplug heats up and shuts off as it should when the sensor tells it to, but there is no clicking to the pump. The pump is fine, I’ve actuated it manually and it pumps fine. There is however, no pulsing to the pump. Both cables are showing 12v from earth. Does anyone have a schematic for the control unit? I’m not adversed to a bit of soldering and checking of little components, but I’m not really sure where to start! Any advice would be really appreciated!

Thanks

Steve

[Oldiebut goodie]

If you are looking for schematics for the ecu you are out of luck - such a thing doesn't exist in the wild. (I presume that this is what you mean by control unit and not control switches etc)
You shouldn't have 12v on both wires to the pump though - are you using an analogue meter? - as a digital one will be unlikely to show the pulses if they are quick.Also what point are you using as the earth reference point, Eberspächers tend to have 2 earths that are not interconnected! Make sure that you are checking using an earth at the ecu as chassis earth can be different - saw this on a D2.
If you are certain it is the ecu all you can do is open it up and check diodes etc around the fuel pump relay Including the relay itself (they can stick after many years use especially the contacts) You may well have a bad joint or 2 which isn't unusual after 20+ years, good magnifying lens needed.Usually the spade contacts fail at the board soldering.
I hope that you didn't test the pump whilst it was still connected to the ecu - easiest way to fry the ecu! You are certain that it is a 12v pump and not 24v - not hard to mix up when covered with crud as you can get a 24v pump to fire with 12v when empty and not once fuel is placing a load on it.
I have a Dutch workshop manual and English installation manual if needed.
What sort of thing to expect inside: (not B3L)

[California Dreamin]

Oldiebut goodie is your man but one simple check...did you take a look at the fuse 'IN the control relay? I believe that the pump stops working if this blows (small glass fuse). The fuse holder is accessible from the outside.

Martin

[Oldiebut goodie]

I don't think that he is playing with us anymore!