Esa/asr fault on project c4 picasso mk1 2013

[vincentfishing]

Bought c4 picasso cheap as project, came with esr/asr fault drove fine no limp home mode, came with spare new wishbone/droplinks / ball joints, also had new pads n disc's, new tyres, so worth a chance at trying to fix . Fitted everything,did tracking, fitted new front wheel bearings, also tested all abs sensors ,all good no faults . Tested egr all good ,disconnected all ecu plugs and checked wiring replaced small damaged section on ecu ,but didn't cure fault.
The faults are
U1218
C1391

I have crawled the net looking at reasons and ideas, know the citroen definitions and effects/parameters of the codes ..
I think I may have an injector 3 problem which will be next on my list as I do have a diesel knock under load and when I checked diagbox on the injectors,all had injector readings except no 3 ,see pic which maybe someone can enlighten me on as there are no injector faults showing !

[RichardW]

Those are just coms codes, so you are looking for a fault elsewhere, probably in the engine ECU. Are there any in there? The injector might just need programming if it's been changed.

[vincentfishing]

No injector changes no other faults on global test, still think it's strange 1,2 and 4 injectors have readings but 3 doesn't combined with injector knock......

[vincentfishing]

Drove for a couple of days on temporary insurance and injector 3 needed to complete a learning cycle which it did,no further problem with knocking ,( think I had accidently wiped injector 3 readings on diagbox when delving deeper than I ever have on diagbox , still haven't resolved esa/asr fault , all actuator tests on everything passed, abs readings on all 4 wheels good, can clear the c1391 fault on individual test of abs/traction control, but when I restart global test it comes straight back on( with no driving of car) also noticed( and it may be normal) that when global test picks up the u1218 there's a loud thunk behind console and the same thunk when it picks up the c1391 like a relay is being activated /deactivated is this normal ?? , just a note,there is no limp mode and auto handbrake works fine, when I got car I found scuttle drains were blocked so lots of water sloshing round in scuttle,now thinking I need to check out back of bsi and local wiring for damage ?when I checked abs ecu all power wires etc had continuity but havnt checked everything individually which will be last attempt after bsi check, Open to any thoughts / ideas that might help, thanks.

[vincentfishing]

Having taken wiring connectors / plugs etc and put them all back together I am down to the 1 fault c1391 and still have esr/asr light on.
As previously stated I can clear this fault and as soon as I rerun global test without starting engine it comes straight back on,
The only 2 things that look strange when I look at fault details are that I have reading for yaw angle speed 27 deg/s and transverse acceleration 2.6m/s,, even though car is stationary when the fault reappears, is this normal to have these readings ???

[vincentfishing]

Today ,I decided to check live dynamic info
steering angle = good
Yaw speed angle 0deg =good
Longitudinal acceleration 0= good
Transverse acceleration 2.6m/s = ???
Expected a bit of error possibly but is this acceptable ?? Shaked the car left and right and reading went up and down accordingly ,so it appears to working, but to think it's moved 2.5meters in a second doesnt sound right, did a recalibration and didn't change....
Any thoughts anybody ???

[vincentfishing]

Have ordered used yaw sensor off ebay to try fitting and calibrating and ruling out one more thing, bit of a pain getting to it !

[vincentfishing]

Still have just one esp/asr fault showing up c1391, have discovered that the "thunk" noise on the global test is the abs unit by front wheel activating, when the global test thunks in the engine/injection part of global test ,no fault ,when the global test moves down to the abs ecu and thunks, the fault shows up( having previously been deleted ,engine not running.) As I have no other faults to guide me and checked just about everything my next plan is to replace bsm with cheap second hand one as it's easy and it is linked to abs ecu,then if that fails will try replacing abs ecu if I can find matching numbers part cheap enough, not willing to put anymore money than that into this.