ZFE replacement?

2007 RT

Three weeks ago I had the RaceTech suspension refreshed at the Corona shop. Bike was sitting too low, so I took it back and they adjusted it for me. The ride hight is good now, but I can't adjust the preload.

At that time we tried cleaning and adjusting all the plugs. No Go.

Disconnected the battery and reconnected it. The preload worked four times. Turned bike off, and it wouldn't work when turned back on.

After that, nothing we tried got it to go. The RaceTech guy called his "BMW Master Tech" buddy who told him the ZFE just needed a "reflash".

So...

Took it into the local BMW shop today and

ESA - Dampening adjustment works fine, but preload will not adjust.

they were able to move it during a "function check". They reprogrammed the ZFE, but that did not fix it.

They tell me I need a new ZFE. $1100+

Anyone know if this might work, Or am I throwing my money away?

Lord knows I don't have much of it to throw...

2007 RT

Three weeks ago I had the RaceTech suspension refreshed at the Corona shop. Bike was sitting too low, so I took it back and they adjusted it for me. The ride hight is good now, but I can't adjust the preload.

At that time we tried cleaning and adjusting all the plugs. No Go.

Disconnected the battery and reconnected it. The preload worked four times. Turned bike off, and it wouldn't work when turned back on.

After that, nothing we tried got it to go. The RaceTech guy called his "BMW Master Tech" buddy who told him the ZFE just needed a "reflash".

So...

Took it into the local BMW shop today and

ESA - Dampening adjustment works fine, but preload will not adjust.

they were able to move it during a "function check". They reprogrammed the ZFE, but that did not fix it.

They tell me I need a new ZFE. $1100+

Anyone know if this might work, Or am I throwing my money away?

Lord knows I don't have much of it to throw...

Evening Don

Yes, it M-I-G-H-T work, but it also might not work. That is a lot of money for a "might" help.

Your best guesser on this is the tec that worked on it. (do you trust him?) -- If not then find another shop.

Thanks for the quick reply DR.

To be honest, I don't fully trust any tech with my baby.

That's why I've always done my own maintenance.

But having two techs tell me it's the ZFE kinda leaves me with no choice but to take their word for it and hope for the best.

Electronics...

Could it be the strut itself that's not working properly?

The preload on my OEM strut stopped woking a while ago.

I was able to make mine work manually using a battery. (not every time though)

Replacing it solved the problem

YMMV

I gave up on my ESA preload. My ZFE reports the sensor (potentiometer) is out of range and refuses to change. It was, by about .01 ohm, IIRC (this is from memory, I'm not near my notes). I bought a used low mile unit which is NOT out of range, and I get the same error. I checked the wiring all the way back to the ZFE, and am convinced the problem is the ZFE. Dealer looked at it and is not willing to guarantee a re-flash will fix the problem. I think BMW changed to a hall effect sensor in 2008 to avoid this sort of problem. Updating an earlier bike runs $2400+ for a new shock, plus $800+ if a new ZFE is needed, plus labor/programming time. I'm not spending that on a ~$6K bike, just to end up with the stock shock.

For now, I've removed the preload motor (spring compressor needed), leaving a hex shaft that lets me adjust preload with a deep socket. Another 10K miles or so and I'll put on a better set of Tractive or Yacugar shocks from BeemerShop. If I want, they can set up the Tractive shocks to retain the electronic damping control and provide a manual preload adjuster.

Thanks for the quick reply DR.

To be honest, I don't fully trust any tech with my baby.

That's why I've always done my own maintenance.

But having two techs tell me it's the ZFE kinda leaves me with no choice but to take their word for it and hope for the best.

Electronics...

Morning Don

If the tec was able to move it during the function check that tells us that the rear strut is at least responsive & the ZFE should be able to control it.

Any idea on any CIP codes that were showing , or were read during the hookup???? (this could tell us something)

You might ask the tec if he is familiar with service bulletin 61 001 08 (015), Date: 03/2008. That covers a non responsive rear strut & gives a later CIP (update) that raises the ZFE power threshold going to the rear strut.

Have you tried moving the rear preload with the bike on the center stand (that takes some of the static load off the adjuster mechanism). If it works better on the center stand then that could also tell us something.

Morning DR,

No idea on the codes. They don't let us "regular folks" into the service area.

Thanks for the service bulletin number. I'll ask.

As far as trying the preload while on the center stand, I don't think that would do any good at this point.

After the second visit to RaceTech, pushing the ESA button will only change dampening. For preload, it shows one helmet on the display, period. It will not even attempt to change when I hold the button down.

This is what is written on the Service report:

"75478 It has potentiometer ESA. Preload adjust moves when performing function check, but cannot calibrate.

Re program ZFE did not fix. Following ISTA to do line, insulation, component test and everything fine. ZFE should be replaced"