How many ABS sensors are there on a 2003 mk 3 2 tdci
 

Hi my garage is saying the ABS light flashing is a sensor problem .I have replaced one and now they say I must replace 2 more .The car has 75000 k on it and tto replace them in Bangkok is 10000 baht about 300US .Any ideas guys and gals ?

One of the ways to check and confirm ABS utilizes the use of a good scan tool.
If there is a faulty wheel speed sensor the tool should tell you which wheel, at least.
There is the possibility you might be getting misled.
Sometimes it is better to pay for a good diagnosis so you get the correct info.
What if you tried another shop?

One needs to remember that a new ABS sensor will normally put out a stronger signal than the older sensor that is still in use. This would cause the older sensor to cause the ABS system to report another sensor issue. As HANKY stated, a good scan tool is needed. One that will provide the ABS sensor signals for comparison will help. Another shop diagnosis sounds like a good call.