ST1100 - more ABS help needed.....

simonhodge

Joined
Aug 30, 2009
Messages
18
Location
Newtownards, Co Down
We for those that viewed my last thread about ABS will see that it was nothing more than a power problem which is sorted. This morning though it started flashing as soon as i set off to work!:mad: Once i reached work i did what was needed to get the code from it and its flashing twice. From what i can find this is the following:

Faulty rear modulator crank angle sensor system

Can anyone give me a hint as to what is actually wrong as this doesn't mean a lot to me?

Thanks
 
The ABS modulators have a sensor in them that tell the computer how the pump is physically positioned so it can best modulate the brakes when you lock a wheel. The error code says that the computer isn't able to read that sensor, or it's getting unexpected readings back.

I note that you're in the UK, which seems to subject bikes to more salty spray and crud than the rest of the world. In that kind of environment, the low-hanging fruit would be an electrical connection gone bad. I would suggest that you remove enough plastic to get to the rear modulator, disconnect the electrical connector at the end of the pigtail, give both sides a good blast of a high-quality contact cleaner, let them dry out, reassemble and test.

--Mark
 
I found the connector and sprayed into both ends. To be honest it was spotless in both ends. No joy so far.

What about the sensor at the actual wheel. Is there any point in looking at it?
 
You could have a look, but that's not the sensor it's complaining about.

Is there any chance the problem is at the other end, where the harness plugs into the ABS computer?

I'm really just shooting at the easy ones here; it's entirely possible the sensor in the modulator has failed. Someone else in the UK had the same problem with an 1100, and I forget how it was resolved.

--Mark
 
If i hit the ABS button while riding the light stays red but stops flashing. Once i stop and restart the bike it just starts flashing again. I tried changing the fuse just in the off chance but no joy! Not sure what to do now. Guess i am going to have to go and buy some new bits.:(
 
The rear sensor is well known for failing, with the computer then giving an error code for something completely different (and more expensive).

I'd try replacing the sensor first (look for a used one). Or put the front sensor on the rear and see what happens - different cable length but will still work.
 
And the saga continues, i get on the bike this morning as usual to go to work, but this time the ABS light goes out as it should once i set off. So i am none the wiser now. Obviously it was just having a few off days and now its feeling better again.;)
 
Hi Simon

Find some where very quite with a clean surface and plenty of run off and try the ABS. I don't want to be a kill joy but, don't think that because the inicator lights are now functioning as they should that the system is operating normally. It's not always the case. DAMHIK. Better to check than need the ABS and not have it.
 
alphafang said:
Hi Simon

Find some where very quite with a clean surface and plenty of run off and try the ABS. I don't want to be a kill joy but, don't think that because the inicator lights are now functioning as they should that the system is operating normally. It's not always the case. DAMHIK. Better to check than need the ABS and not have it.
Click to expand...

Good point.
 
If the lights come on with the ignition and go out after the first few seconds of movement, the ABS is working fine. The ECU checks everything.

The faulty crank angle warning could be:
i) The fuse has blown.
ii) The crank cannot turn. I had this once when Id been fitting new brake pads, and didn't release bleed afterwards to release pressure. (At least thats what I think caused the problem).
iii) A similar problem occurred which I cleared by unplugging the ECU for a few minutes.

See http://www.jfheath.co.uk/st1100t/abs.htm

When you turn on the ignition, the ECU attempts to turn the crank motors which pulse the braking system. (One near fluid reservoir, one near radiator cap). If you can't hear this happen, or feel the click when touching the motors, then they aren't working.
Check - in order of ease of access.
fuses
connectors
too much brake fluid as a result of pushing pistons back into callipers
ECU connections
 
You must log in or register to reply here.
Back
Top Bottom