abs wheel sensors

[mental]

hi all
need a little help with my 98 turbo the code reader says the abs speed wheel sensors are at fault not having this kind of prob before i would like to know what they do where are they and are they easy to change.
thanks for your help.

[luellin]

ok dont quoate me on this i think there the little magnets that hover over a disc attached to yout break discs that look junda like a punch card metal open metal open and so on hard to xplain but easy to change if there the problem

[rubjonny]

yeah they're bolted to the wheel bearing/caliper carriers, follow any wires to the wheel area and you';ll spot em. sometimes can get away with cleaning the sensor and the trigger wheel, sometimes one or both need replacing. while the wheel is off take a good look at the trigger wheel, if it looks ropey then advisable to change it. in an ideal world they're swapped whenever discs are changed, but this doesn't always happen

[mental]

just had the wheels off found the sensors the prob looked obvious apart from needing new discs soon a load of chunks of rust was spinning round in the disc and getting trapped in the sensor wheel holes.
got them out erased the codes and all seems ok so far.
thanks