No preasure to front o/s brake

Hi, new to forum so please be gentle.
I got my first discovery a couple of months back as a project. One small job was to replace small section of brake pipe from caliper to flexi on both front calipers. On bleeding all was fine on n/s but on o/s got an issue. It started bleeding through ok no probs then once good fluid was coming through it just stopped, with the pedal going hard as though I'd closed the nipple. Back tracked pipe back to abs pump undid that still no fluid. Undid all brake pipes and cleared with air, reassembled and bled starting at o/s rear working clockwise. Got to o/s front and started to bleed through, until as soon as clear fluid starts to flow it shuts off as nipple closed.
The abs light has always been on since I got it but as it's not on road yet didn't worry too much about it. Did paper clip test and got 2-12 & 2-14 I'm led to believe this is air gaps on both front sensors. Pulled bridge to clear codes and still got 2-14 as a fault but 2-12 has cleared o/s front I believe. So tried bleeding it again it started to flow ok but than same as just stopped with pedal being hard.
Any help on this would be gratefully received.

Any fluid leaking out of the brake system? For example overnight?

I had a fractured copper brake pipe on my Defender that caused a total disaster of 100% brake failure and that was originally a fracture on one side.

No leaks, all pipes and connections checked,

Possibly, you now have air trapped inside the abs modulator, if so I believe the valves have to be opened with the aid of Testbook or similar to complete the bleeding of the fluid.

Thought of that but, all other brakes ok and if valve shut due to a fault / air in system would this not show as a fault code. Just wondering if list of codes I found has got them mixed up as I have code 2-14 showing only. The list I found shows that as being front left sensor air gap too big, now it am going on the fact that left hand side is near side and that's ok ( obviously has an abs sensor fault that needs addressing ) i could understand the valve shutting off if the fault code related to that wheel. As for test book, surely all that would do is control a relay / solenoid to open it via the abs ecu? Which would be open with battery disconnected anyhow or all other valves would shut????? Would'nt they???

Roders1 said:

Thought of that but, all other brakes ok and if valve shut due to a fault / air in system would this not show as a fault code. Just wondering if list of codes I found has got them mixed up as I have code 2-14 showing only. The list I found shows that as being front left sensor air gap too big, now it am going on the fact that left hand side is near side and that's ok ( obviously has an abs sensor fault that needs addressing ) i could understand the valve shutting off if the fault code related to that wheel. As for test book, surely all that would do is control a relay / solenoid to open it via the abs ecu? Which would be open with battery disconnected anyhow or all other valves would shut????? Wouldn't they???

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Might I make a suggestion? There is an electrical connector close by the abs pump/modulator. If you disconnect this all valves should open, allowing you to complete you bleed sequence, then reconnect.


Dave

Thanks Dave, I'll give that a shot and see how it goes.

Sorted, first thing thanks for the replies.
Today is first chance I've had to spend a bit of time on it. Starting at the offending caliper I cracked off pipe connections one at a time while my lovely assistant worked the pedal. Nothing, right upto and including the output from the pump. Did this a few times, with battery on, engine running, battery off ect. Still nothing. So my train of thought was it has to be a stuck valve ( as with battery off all sensors are in affect off, so all valves should open) ( a fail safe system). So, with output from pump to offending wheel cracked open whilst assistant was pumping on brake pedal I started to tap the pump around the area with a small hammer. After about 15-20 taps fluid started to dribble from output so continuing to tap eventually started to get a good jet of fluid going. Tightened all pipes, then bled all wheels, drove up and down street a few times and bled offending wheel again ( just to check fluid flow). Hey presto all ok. So even if it's only a temporary fix, at least I know it's the pump that needs to be replaced or repaired.