Key fob dead

[flybobbie]

So drove today, back DSC abs like christmas tree on. No hill start, so surprising how you after be quick off the mark.
Something else i noticed, ebrake on light flickering, like a bad contact somewhere.
Abs dsc warning goes when engine is restarted.
Now trying to find the common denominator of;
6E30DSC hyd. ctl. unit press. sense plausibility,
6570 DSC interface,
63F1EPS steering wheel angle.


Also the B4 Bilsteins i fitted whilst driving today made roof and mirrors resonate, stopped when i dropped tyre pressures down from 38f and 40r (what i have run for years) to 35psi all round. (Made no difference day later).

 

[flybobbie]

Something i will look at, the scuttle drains.
I seem to remember one is above the abs unit on the left side.
Check for any corrosion on the abs plug because everything abs, brakes, etc. goes to this plug..

 

[flybobbie]

So cleaned abs plug, made no difference. Fault came back up.
So went on a run with Foxwell set to wheel sensor in graph mode, set to rear wheels, record mode. Abs warning came up again.
It clears on restart.

The two speed lines would match on the straights but would see a random spike on the left.
But having fitted the B4 shocks, there seems a vibration being picked by the mirror glass and roof rattle.
Never seen that with B6 shocks.

So have a choice now, i have replacements wheel sensors, but they could be ok.
Replace the B4's back to the old B6's and see if any different.

Could the B4's be faulty or just not suited to the set up, unlucky resonance.
Is the system seeing some sort of random skip and flagging as a fault.

I should be able to download the graph, signed up to Foxwell, but now won't allow me to link.
Doesn't seem to allow replay on the reader itself.

 

[flybobbie]

So new wheel sensors fitted.
Hope this cures ABS problem.
Only driven few feet forward, but brake pedal seems more powerful.
One code that came up each time was abs pressure sensor plausibility.

 

[flybobbie]

No joy, 5 minutes into journey, bong.
I do notice the park brake icon when red, sometimes flickers, like a loose wire somewhere.

All resets if i switch off ignition/engine and restart. Then 10 minutes later, bong.

Something else i noticed on the obd readout was the accelerometers, they show a flickering longitudinal -0.13 average number.
Transverse says -0.2
Should these be zero when not moving.
I noticed when i lifted the carpet with seat removed a black box mounted to floor.
Think this might be the accelerometer.
Wonder if damp got to it.

 

[flybobbie]

It seems BMW supplier in their wisdom $$$$ built the pressure sensor into the abs unit, whereas for previous 20 odd year it was on the side, easy to replace.
Looking at minimum £300 rebuild.

Anyone have any links to diy repair.

 

[B21]

I think the lateral accelerometer is integrated into the DSC unit ….

 

[flybobbie]

Just a bit odd they don't read zero. Perhaps just noise. Thought there would be some hysteresis to stop being over sensitive.

Turning into a Apollo moon rocket problem.

Just don't want to waste 300 quid.

 

[flybobbie]

Brake pressure at foot pedal reads normal on obd.
Fact it resets on starting, wish it would just fail and be done with.

 

[B21]

Just a bid odd they don't read zero. Perhaps just noise. Thought there would be some hysteresis to stop being over sensitive.

Turning into a Apollo moon rocket problem.

Just don't want to waste 300 quid.

Pass..are you sure someone is not spraying acetic acid every night into all your connectors?

 

[flybobbie]

Someone or thing is telling me something.

 

[flybobbie]

So i noted today the error came up the bottom of a hill at a junction.
And when park brake applied the red P symbol flickers, like a bad connection then stays on normal.

Put an offer on an abs unit with the intention of swapping over the mechanical parts.
But gut feel is it's a wire problem.
Obd says
6030 parking brake ctl unit undervolt
6570 Interface dsc
6E30/not present dsc hyd. ctl unit press sense plausibilty
5F45/dsc brake fluid level too low
Brake fluid level not ok

Again it could be the level sensor is not a simple switch, but is shown as such in diagrams.
Unfortunately switch is molded into reservoir, so would need to replace all, need to see if it has any resistance or if there is a common supply with the flickering brake applied icon.

 

[flybobbie]

OK just about fallen out of love with this car, i was seriously going to get rid or part ex.

Always liked the look and interior, but drives awful, worst car i have ever owned for simple driving pleasure.
I know today was a cold morning, but every slight undulation the cars unstable.
It's like being a racing or rally driver to steer straight, my bus. partner said the same about her car.
As i get older my senses are numbed a bit, i need something that drives like it's on autopilot.

So driving to work, usual spot ABS fail! Just after applying the brake.
So at traffic lights switch off ignition to restart and reset the ABS.
But car wouldn't start.
Several presses, couple of times slight starter engage then finally started :evil:
Then 2 more abs fails by time i got to work.

So my suspicion is going back to the brake light switch.
I think tomorrow i will seek out a genuine BMW switch ( Buy genuine ).
(I did order one from BMW, hopefully still on the shelf).

 

[ronk]

You deserve a medal!

 

[flybobbie]

Cut open old switch

Days of simple contact switch have gone. Hall sensor with magnets on 3 sides.
Can see bottom left some burning that i could smell.

I wonder if it has does some damage elsewhere causing the abs problem, or aftermarket switch just rubbish quality.
Certainly the one from Eurocarparts didn't work correctly.

 

[B21]

I feel 5 litres of 95 octane and a box of Swan Vestas coming on…

 

[flybobbie]

So BMW had to reorder in the brake switch, as they return after 7 days if not collected.

2nd ABS as arrived, so will first try swapping the electronics module over.
Hopefully being off another 23i it might not need coding.

If all works fine will cancel switch save £40.
I think the non start was my covid addled brain pushing on brake pedal instead of clutch :?

 

[flybobbie]

Inside 2nd hand ABS.
Electrics in separate module held by 4 screws.
Try module first save disturbing the hyd. lines.

 

[ronk]

What happens after you've sorted the problem?
(You have certainly demonstrated your perseverance so far )

Are you going to give it another chance or is it going to be changed?

 

[flybobbie]

I shall keep it.