ACS not working

Having Problems with your BMW R1200RT/R1250RT? or have some Maintenance and Service questions?
Post Reply
User avatar
Doctor T
Posts: 2646
Joined: Tue Dec 21, 2021 10:21 pm
Location: west sussex
Bike Model and Year: 2007 R1200RT SE
Has liked: 1695 times
Been liked: 549 times
Great Britain

ACS not working

Post by Doctor T »

Up until last Tuesday, my ACS seemed to be working fine. no warning lamps. Then my battery failed. Whilst trying to get home without stalling, i noticed the speedo had stopped working. Got home, fitted a new battery, and the speedo worked, but now my ACS lamp will not stop flashing. I've plugged in to GS-911 and report no faults. Is the rear speedo sensor connected to the ACS sensor?. The handlebar seems to work and is clean on the contacts.
If so, why does the speedo work as it should, but the ACS is not now? This only started when the battery went flat.
I've removed the speedo sensor and can not find any problems or any wiring faults.
Trust me I am a retired Doctor and lecturer at Oxford University of Structural and Mechanical/Electrical engineering.
May the shaft be with you
User avatar
David.
Subscriber
Posts: 8762
Joined: Fri Nov 07, 2014 7:29 pm
Location: North Yorkshire
Bike Model and Year: R1200RT (Camhead) 2012
Been liked: 506 times
Great Britain

Re: ACS not working

Post by David. »

Just a thought, does the ASC system rely on the ABS system being functional.
User avatar
Doctor T
Posts: 2646
Joined: Tue Dec 21, 2021 10:21 pm
Location: west sussex
Bike Model and Year: 2007 R1200RT SE
Has liked: 1695 times
Been liked: 549 times
Great Britain

Re: ACS not working

Post by Doctor T »

No, my ABS hasn't worked for over 5 years, going by the service history
Trust me I am a retired Doctor and lecturer at Oxford University of Structural and Mechanical/Electrical engineering.
May the shaft be with you
User avatar
Stu
Administrator
Posts: 1998
Joined: Wed Jun 02, 2021 9:13 pm
Location: Hull, UK
Bike Model and Year: 2016 R1200RT
Has liked: 696 times
Been liked: 729 times
Great Britain

Re: ACS not working

Post by Stu »

usually ABS and ASC use the same sensors

How far have you riding on the bike? sometimes they require a bit of a ride for it to re-learn.
User avatar
Doctor T
Posts: 2646
Joined: Tue Dec 21, 2021 10:21 pm
Location: west sussex
Bike Model and Year: 2007 R1200RT SE
Has liked: 1695 times
Been liked: 549 times
Great Britain

Re: ACS not working

Post by Doctor T »

About 10 miles
Trust me I am a retired Doctor and lecturer at Oxford University of Structural and Mechanical/Electrical engineering.
May the shaft be with you
User avatar
Stu
Administrator
Posts: 1998
Joined: Wed Jun 02, 2021 9:13 pm
Location: Hull, UK
Bike Model and Year: 2016 R1200RT
Has liked: 696 times
Been liked: 729 times
Great Britain

Re: ACS not working

Post by Stu »

more than enough to reset it
User avatar
Doctor T
Posts: 2646
Joined: Tue Dec 21, 2021 10:21 pm
Location: west sussex
Bike Model and Year: 2007 R1200RT SE
Has liked: 1695 times
Been liked: 549 times
Great Britain

Re: ACS not working

Post by Doctor T »

That's what i thought. The sensor cable houses wires for the ABS, Speedo, and the ACS. There are no nicks or cuts in the outer covering, and I've never touched the cable or the sensor. I will ask the dealer how much this cable costs and to make sure the switch to, i betting they cost an arm and a leg.
In the meantime, i can live with it. Its only like having no traction control. Can't think of any bikes I've owned that had TC
Trust me I am a retired Doctor and lecturer at Oxford University of Structural and Mechanical/Electrical engineering.
May the shaft be with you
Post Reply