Can't get it up

The shock will have built in limit switches of some sort. Otherwise the motors would soon overload. You could do yourself a diagram and mark out what happens when you power the connections. At least BMW are consistent with brown wires = earth. I can't imagine ESA is any different.
 
The shock will have built in limit switches of some sort. Otherwise the motors would soon overload. You could do yourself a diagram and mark out what happens when you power the connections. At least BMW are consistent with brown wires = earth. I can't imagine ESA is any different.

They have Hall sensors (later models like mine do anyway) that I presume allow the ECU to count the number of turns the motor has made. Using a GS911 you can calibrate the suspension and it will tell you the range of movement (in number of turns I assume) and where the suspension currently is. I understand from the GS911 forum that for the front low is 3% of the available range, low mountains is 50%, and high mountains is 97%. This is all controlled by the ECU. The trouble is that my ECU and those hall sensors aren't communicating. its either the sensors gone awol or some code in the ECU gone corrupt. When I do an ESA calibration on the front I get "0" and "0" for the range. Basically the ECU doesnt know where the suspension is and neither do I.
 
Hmm not good. Presumably there is one sensor with a number of magnets on the height adjust mechanism.

There will be limit switches to prevent damage at end range but obviously no good for knowing where on the scale the height settings are.

Can the guys at Revs Racing offer any suggestions?
 
Can the guys at Revs Racing offer any suggestions?

According to them they have never known an ESA unit fail on a BMW. They have offered some help swapping out units if & when I need it though. Jimmymac is going to loan me a known to be good shock and motor in a couple of weeks when he is passing. I will hook the shock and motor to my loom; if I cant activate his ESA motor from my button then its probably the software or the central electronics ZFE unit that's got the problem - something for BMW only I suspect.

However it may still prove cheaper to remove and sell or part ex my WESA shocks and fit some non ESA shocks. Something I need to explore with Revs as I believe they do do part ex on their shocks, i.e. Wilbers for Wilbers.
 
I have OEM non ESA shocks. I miss the ESA to be honest.
The ride is harder so bike sits even taller.
Front ride height adjustment is a nightmare (C spanner type). Rear is on minimum preload even with luggage.
Wilbers of course will sort all that but when I do take the plunge I will go for ESA.
 
Well, the bike went into Bowker BMW today after testing with jimmymac's sock/ESA motor didn't take me anywhere. Good news and bad news I suppose.... the good bit was that they "only" charged me £36. The bad was that they don't know what's up with it. Its got them stumped and they said they have never seen anything like it before on any bike. The nearest that have seen is when a race team removes multiple electronic parts from S1000's that they don't need. The bike tends to start shutting down other components that receive inputs from these removed items.

The situation now is that the fault code has gone away. It went after I hooked up the shock I borrowed from Jimmymac with a known to be good ESA motor (it didn't work with this either). However the ECU and my ESA motor still won't "talk" to each other. Bowker's said they never seen that before, i.e. no fault and not working and in their opinion it could be a loom issue causing cross communication and confusing the ECU, which then stops trying to talk to the ESA motor. Fixing it could be ££££ while they run through the loom looking for faults. Err, no way - which they expected. The other thing is that in messing about with the ESA motor, specifically banging 12volts into it, I may have screwed it up. Other than that they couldn't suggest a way forward - oh they could but it involved giving them a signed blank cheque - a proper wallet hammering.

My options seem to be:
1. push 12volts into the rear shock motor and get it approx onto the rider+pillion (two helmets) setting.
Pros: Cheap. I still have ESA for the damping.
Cons: Risk of screwing up the rear ESA motor. I have to ride all the time with the bike on stilts - it would effectively be in the off road "high mountain" position as the front is already up. Resale value if I ever sell is seriously down (although by then mileage will be over 100K so probably not a huge impact on value). Feels like a work around rather than a fix.

2. Replace rear or both shocks with non-ESA Wilber's (or A.N.Other brand).
Pros: gets me adjustment for solo & pillion use albeit manually. I can offset the cost by selling the WESA shocks (still probably about £500+ to swap); I lose an electronic dooh-dah that is IME a weak spot. I get some brand spanking new shocks (again). Permanent long term fix.
Cons: No ESA at all. Quite expensive. I lose an electronic dooh-dah that is a major feature of the bike; Resale value loss mitigated by still having quality adjustable shocks (some may see as a bonus anyway).

3. Do my own investigations into the loom and the ESA motor.
Pros: It might be cheap if I can find and fix the issue. I get a fully functional ESA system back. A proper fix and the glowing satisfaction of DIY.
Cons: Nobody is 100% sure its a loom or ESA motor fault. I don't really have the skills or knowledge or tools (a GS911 is not good enough) to do this properly (I have already just about exhausted my skills on this). Huge risk I screw up something else while testing circuits. I will probably need to buy a used ESA motor for testing, parts or as replacement when I completely screw up the existing one after taking it apart. Bike off the road for an extended period while I investigate Cost of electrical parts +used ESA motor may work out about the same as option 2.

4. Give it to an expert (BMW Motorrad or an independent) with the full diagnostic suite and the skills to rectify electronic faults.
Pros: It will get fixed. I get a fully functional ESA system back. A proper permanent fix. If fault is easily and quickly found it could be cheap.....
Cons: .... but more likely could be hugely expensive in labour and parts.

5. Do nothing.
Pros: Cheap. ESA for damping still works. I have a good excuse not to take the wife out on the bike.
Cons: We use the bike a lot for UK and overseas trips two-up with camping gear. It really needs to be raised at the rear to keep the bike level, stop it from bottoming out and dragging stands and pegs on corners. Extended use this way likely to cause premature wear on shock and other suspension components.

At the mo my preference is option 2 replacing both shocks. Any thoughts?
 
A little confused about the mechanic's findings. If I have it correct - connecting a known good ESA shock cleared the ECU faults but the shock would not move?

That sounds like a wiring issue to me.

(1) Wires in a fixed bundle can chafe, but rarely break.
(2) Wires can break (or chafe) where the loom moves - steering etc.
(3) Your control button operates the damping but not the ride height.

Checking the loom from ZFE back to the rear of bike can't be too hard a job. Look for chafes under clips and support tray etc. Self amalgamating tape will repair rubbed insulation and re-wrap the loom. A pin pricked through the insulation allows you to continuity test a length of wire (though probably not on the fine canbus wires).

Maybe the switch is connecting well enough for a short pulse to change the damping but is not connecting cleanly enough for the long press to select ride height. So it's worth checking out the microswitch and wires to the ZFE from the handlebar. Can you rig up a test switch directly at the ZFE or is it all Canbus?

Have Revs Racing (Wilbers UK) come across this problem?
 
Agree rig up a test switch straight to the ecu,.
Check the continuity of the 4 wires ecu to pre-load motor on shock, preferably use a loaded continuity tester to test the loom, ( an old 50w sealed beam unit is as good as anything)
Option 6. for the meantime I would machine a 10mm spacer and fit it between the pre-load motor and the spring.
 
Agree rig up a test switch straight to the ecu,.
Check the continuity of the 4 wires ecu to pre-load motor on shock, preferably use a loaded continuity tester to test the loom, ( an old 50w sealed beam unit is as good as anything)
Option 6. for the meantime I would machine a 10mm spacer and fit it between the pre-load motor and the spring.

Maybe a split spacer with groove to align a twisted wire or zip cable tie.
 
A little confused about the mechanic's findings. If I have it correct - connecting a known good ESA shock cleared the ECU faults but the shock would not move?
Correct. Jimmymac dropped by with his shock. I connected it to my loom and in hope and expectation pressed the ESA button. Nada. I connected the GS911 and there was no fault showing anymore. I then tried an ESA Calibration, again Nada other than a slight twitch of the shock (which tells me something is happening just not what the ECU expects). After Jimmy left I reconnected my own shock up and bingo, two long presses of the button got me 2 helmets and a 3rd press got me low mountains. But even after leaving for 2-3 minutes the low mountain icon hadn't started flashing and nothing was happening. After recycling the ignition I was back to square one, i.e. no response from the switch, BUT also still no fault code. Very strange all that.

SO, of course when I took it to BMW they also couldn't see the fault and what puzzles them, and what they have never seen before is an ECU managed component not working but no fault code showing (and no other explanation like some other component removed). I don't exactly know what they tried, but they said without further investigation into the loom there was not a lot they could do. TBH I got the impression they didn't want the job either.


That sounds like a wiring issue to me.

(1) Wires in a fixed bundle can chafe, but rarely break.
(2) Wires can break (or chafe) where the loom moves - steering etc.
(3) Your control button operates the damping but not the ride height.

Before I go down the loom route I think I want to retest with a known to be good ESA motor. Nothing on eBay at the mo.

Checking the loom from ZFE back to the rear of bike can't be too hard a job. Look for chafes under clips and support tray etc. Self amalgamating tape will repair rubbed insulation and re-wrap the loom. A pin pricked through the insulation allows you to continuity test a length of wire (though probably not on the fine canbus wires).
A simple continuity test shows the 4 wires from ZFE connector to the shock are all OK.The motor spins up when I apply 12vlts to pins 1 & 4. I need an extra pair of hands to see if anything is coming down pins 2&3 which should be the feed from the sensors.

Maybe the switch is connecting well enough for a short pulse to change the damping but is not connecting cleanly enough for the long press to select ride height. So it's worth checking out the microswitch and wires to the ZFE from the handlebar. Can you rig up a test switch directly at the ZFE or is it all Canbus?
GS911 picks up the switch being pressed. I will give the switch a clean but I doubt it as the "calibrate ESA" feature on the GS911 doesn't work on the front. Its OK on the rear. I am not sure what you mean by "rig up a test switch"? Do you mean intercept the wires to/from the handlebar switch with the tester and try it from there? Its all Can Bus stuff this so I am not sure I want to dig into it

Have Revs Racing (Wilbers UK) come across this problem?
No, they say in their experience never had a failure of shock or ESA motor.



Agree rig up a test switch straight to the ecu,.As above not 100% sure how to do this
Check the continuity of the 4 wires ecu to pre-load motor on shock, preferably use a loaded continuity tester to test the loom, ( an old 50w sealed beam unit is as good as anything)Again, you have got me there. No idea how to do this. I have a multi tester but I guess that only sends a tiny current to test the wires and everything seems to check out
Option 6. for the meantime I would machine a 10mm spacer and fit it between the pre-load motor and the spring.
That might work, but first I need to get the front back down else I will be on a bike on stilts. Also I don't have the tools or equipment to make a spacer or to dismantle the shock to install it. I doubt Revs Racing would do that job either. However a good idea when I work out how to get the from shock down.

......
 
To test the wire’s ability to carry current you need a load. As you say the normal tester only uses a small current.
A 50watt light will provide a 4amp load at 12 volts.
Wire the lamp -ve to earth on one side.
Wire the battery -ve to earth
Connect light +ve to one end and battery +ve to other end.
Bright light = wire is ok.
Dim light = wire is damaged or has a dirty connector somewhere.
Obviously use a sensible size bulb for the job. 21watt (2amps approx) may be safer for small wires.
Mistacat might make you a spacer but as you say the front end needs to come down.

Do you know which end failed? If the back and left disconnected you might be able to get the front back down again. Don’t forget it needs to wind away for quite some time before the unit will drop.
 
To test the wire’s ability to carry current you need a load. As you say the normal tester only uses a small current.
A 50watt light will provide a 4amp load at 12 volts.
Wire the lamp -ve to earth on one side.
Wire the battery -ve to earth
Connect light +ve to one end and battery +ve to other end.
Bright light = wire is ok.
Dim light = wire is damaged or has a dirty connector somewhere.
Obviously use a sensible size bulb for the job. 21watt (2amps approx) may be safer for small wires.
Mistacat might make you a spacer but as you say the front end needs to come down.

Do you know which end failed? If the back and left disconnected you might be able to get the front back down again. Don’t forget it needs to wind away for quite some time before the unit will drop.

Got it.:thumb2 I have a 21w bulb with some wires soldered on already so should be able to right something up. The wires to pins 1&4 load the motor so they should be OK for a decent load. The other wires carry the Hall sensor output so are way thinner. I might try a 10w bulb on them. A job for some time next week as I am busy for the next few day.

The fault code that was there was for the front sensor.
 
For testing hall effect sensors I use a handy little gadget PicoScope 2105.
It turns the laptop into a single channel oscilloscope so i can see and measure the output.
 
Revs Racing use the OEM ESA equipment with new Wilbers springs and dampers. Do they test the ESA before fitting it? Its worth a phone call
 
A couple of other thoughts and perhaps where i should be looking in the loom....For preload to work the bike has be in neutral and stationary, although the start circuit seems to be OK so probably not the neutral circuit. ABS and traction control all seems OK too and the oil level check also only works when stopped. & neutral. Nevertheless a short circuit in one of these could be throwing the ECU. I need to double check the real time values on the GS911. Maybe try with the speed sensors disconnected. Also I have disconnected the battery (again) to clear any electrical gremlins being held somewhere or other, and put it on charge just to see if that helps any.

It seems that the OEM ESA system is made by Tractive Suspension: https://tractivesuspension.com/motorbikes/bmw-esa-products/ and it looks like the ESA parts, as well as the shocks can be serviced by JJ Suspension in Holland. https://www.esarepair.com/esarepair.html?lang=EN The tractive units look to be an alternative to Wilbers and Ohlins especially as they include new beefed up ESA motors.
 
I would say that if the other items that need the bike standing and in neutral are working, then that's not why the ESA refuses to work. However, is the ESA seeing all of those interlocks? Something else to test. :(
 
Well, it's sort of fixed :). I was right to pursue the preload motor as the source of the fault.

I borrowed another shock from another top UKGSer - Pathologic (Nigel). And after hooking his shock to my loom first test was an ESA calibration: all good. After that the dash responded to the button and the my rear shock moved first to two helmets, then both shocks moved to low mountains and again into high mountains. All worked as I cycled through all the options. After disconnecting Nigel's shock but leaving my front disconnected the rear continued to respond to the button. I suppose ought to have checked what happened with the front connected but I thought while it's working I am putting it all back together. Which I did. The rear still now cycles between 1 helmet / helmet+luggage / 2 helmets. The front won't respond as it's disconnected and suspect a fault would show if I attempted to move to low or high mountains. **

I could just leave as is with the risk that it defaults to safe at some future point or I can buy the shock & motor from Nigel and get the guys at revs to fit it to my Wilbers. All is then back to how it should be.


** I think I know why things weren't working. I have been emailing the guys at Tractiv suspension who keep on saying it important the that shock preload is in the same position as the bike thinks it is, i.e. if the dash shows 1 helmet then the shock needs to have ~3% preload added. My front shock was in high mountains despite the dash saying it was in 1 helmet.

Also I now know which way round the preload motor works: Battery positive to the black wire on the motor's loom and negative to red will add preload. Vice-versa will remove preload. I know my motor is stuck or knackered as several minutes worth of trying remove preload and get it back at least close to the 1 helmet setting has no effect.
 
You make a very interesting point about matching of actual and electronic settings. Revs require the shocks to be set on minimum preload AND "Comfort" damping before sending to them.

A stuck motor like that would normally burn out or at least pop fuses. Your strange faults might have been the canbus tripping when it saw an over-current. Opening the motor for a good clean has to be worth a try.

TBH, If you are paying Revs to do the work you might as well pay them for a replacement shock. The OEM shocks are nothing special and prone to letting go.
 


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