BMW R1200RT/R1250RT Forum

David. wrote: ↑Tue Feb 28, 2023 6:39 pm See if you can make any sense of this from Adventure Rider, https://www.advrider.com/f/threads/bmw- ... s.1443073/

some good info on there

Looks to me like the sensors aren't replaceable but the fault could also indicate a wiring fault or corrosion on the circuit board which can be repaired

The rear ABS wheel sensor is faulty according to motoscan. These sensors aren't replaceable? I have seen people replacing them in YouTube videos.
Looking at the circuit diagram, pin 50 of the ZFE unit handles the brake light switching based on info it gets from the ABS Control unit??? There doesn't appear to be any brake switches... Something I might rectify given the questionable brake warning system that could very well cause a rear end collision. Some systems really should not have been subject to ZFE control! Methinks a car designer bent on full canbus implementation has been let loose on these machines causing a wonderful mechanical system to be plagued by pointless, innumerable electronic errors.

Marvin2Shoes wrote: ↑Wed Mar 01, 2023 3:05 amThe rear ABS wheel sensor is faulty according to motoscan.

Marvin2Shoes wrote: ↑Wed Mar 01, 2023 3:05 amThere doesn't appear to be any brake switches.

David. wrote: ↑Tue Feb 28, 2023 1:35 pmThe brake light switches are integral with the ABS control unit.

Some good info. here, https://www.advrider.com/f/threads/bmw- ... s.1443073/

How To Test Wheel Sensors On BMW Motorcycles

Marvin2Shoes wrote: ↑Wed Mar 01, 2023 3:05 amThe rear ABS wheel sensor is faulty according to motoscan.

Is the fault electrical or pressure related.

Marvin2Shoes wrote: ↑Wed Mar 01, 2023 3:05 am The rear ABS wheel sensor is faulty according to motoscan. These sensors aren't replaceable?

An ABS sensor is replaceable but the pressure sensors aren't as they are built in to the pump

The error clearly indicates the rear sensor is at fault. I don't know how pressure comes into the equation? It will either be an intermittently faulty transducer or a cable/connector issue relating to the rear sensor circuit?

Marvin2Shoes wrote: ↑Fri Mar 03, 2023 12:32 pmI don't know how pressure comes into the equation.

Marvin2Shoes wrote: ↑Tue Feb 28, 2023 1:19 pmThe latest output of Motoscan app can be seen in the attached screenshot.

Marvin2Shoes wrote: ↑Fri Mar 03, 2023 12:32 pmIt will either be an intermittently faulty transducer or a cable/connector issue relating to the rear sensor circuit.

This above video shows how to test for this, or just change the sensor after having tested the voltage at the connector.

Oh dear... I have been getting undervoltage and wheel sensor errors and somehow I've not read and realised the error had changed to pressure sensor. I have a wheel sensor on order that likely won't fix the problem. To compound this, I have a local BMW dealer who, given the accounts of their service stuffups in the past, you would never trust with your own bike.
My lack of attention has cost me a couple hundred dollars. Oh well. Sparies.

Marvin2Shoes wrote: ↑Sun Mar 12, 2023 5:33 amI have been getting under voltage.

Has the battery been tested.

I haven't been seeing any undervoltage errors in the last two months and the bike is cranking over normally and has no other errors, just the pressure sensor.

I see I have five possible courses of action...

1. Replace the ABS unit at AU$4000+ if I can find a BMW service tech I would trust to install it and then shell out for motels to get there & back/remain there for the duration of the repair. (we are now talking half the 2nd hand value of this motorcycle ). So not really a fiscally viable option.

2. Bypass the ABS (never had ABS before anyway) but this relies on the electronic ABS board remaining in-circuit so the bike will run. This means if the circuitry fails I need to replace the ABS unit in the future. So only a temporary fix that is affordable in the short term. (maybe sell it at this point at a reduced price with advertised "no ABS")

3. Sell the bike at a much discounted price "as-is" .

4. Sell it off on eBay as parts (but would this just be a lot of work for little gain on option 3?).

5. Remove ABS, ZFE, engine management system, dash display, radio, speakers. Then completely rebuild using 3rd party ECU, instrumentation and rewire to easily serviced 90's style electrical systems.

I think you'd agree none of these options are particularly good/easy.
I am amazed a motorcycle that has done 48,911km (30, 569miles) is in this difficult position.
Between the canbus system, the ABS system and comprehensive system of dealer malfeasance you may end up in my shoes.... beware purchasers of 2nd hand BMW motorcycles.

Marvin2Shoes wrote: ↑Sun Mar 12, 2023 11:59 pmBeware purchasers of 2nd hand BMW motorcycles.

When purchasing a used BMW from a dealer, depending on its' age, it'll come with the remainder of the manufacturers warranty or a used bike warranty. After that and if bought elsewhere, an insured warranty can be purchased (up to 80K miles), providing that the service history is brought up to date.

Marvin2Shoes wrote: ↑Sun Mar 12, 2023 11:59 pmI am amazed a motorcycle that has done 48,911 km (30,569 miles) is in this difficult position.

The bike is 12 years old. From new, was the F&R brake fluid changed initially after one year, then every two years after that.

The service history is a moot point.... what BMW is charging for ABS units is highway robbery. The fact that so many people think that dealer servicing / extended warranties are the answer shows there is little understanding of the incompetence of Australian dealer workshops and even less interest in pushing for motorcycles that are repairable by the end user. I have literally seen $7000 knocked off the value of my bike in six months. This is not normal! I have since met other BMW owners who also thought the value of their bikes would last longer than they have. It's too late for me to recoup my losses... All I can do is relate the ridiculous anti-servicing attitudes of BMW to as many people as possible in the hope that maybe they can dodge this dodgy brand.