thanks for the reply mike very much appreciated. what is not helping is the fact that the two blue abs plugs are missing and i wanted to check there was no volts drop through the wired tempory fix. i will rewire them again and check for the volts at the sensors input/output. again these sensors were from an ebay source fitted by a person unknown. even if the volt checks are good on the multimeter it may be giving varied output signals.best i think to out them and buy bosch or originals is the best move. without plugs its difficult to rewire the new sensors in as you cannot see which wire on the new sensors are for input and output . colours are different on these aftermarket ones.hence the question will the sensor work reversed polarity. just didnt want to damage the new sensors by wiring incorrectly. again thanks for your help. regards ..