The wear sensor is on the front left wheel and may not have been reinstalled correctly. The rear is on the drivers side wheel.
You do need to take the wheels off and check that the brakes are OK and try refitting the sensor - they do just push in and out but be careful doing it. If that does not fix it and if the light annoys you remove the sensor and tie it up to the suspension out of the way - or if you are prepared to sacrifice it just cut the wire near the sensor and tie the wire out of the way - the sensor is a simple earth nothing more so if there is no earth there is no light.
But make sure there is not an underlying problem such as worn or incorrectly fitted pads.
Garry
REMLR 243
2007 Range Rover Sport TDV6
1977 FC 101
1976 Jaguar XJ12C
1973 Haflinger AP700
1971 Jaguar V12 E-Type Series 3 Roadster
1957 Series 1 88"
1957 Series 1 88" Station Wagon
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