Farthing Downs lanes, winter grit and ABS sensor corrosion
Drive the lanes around Farthing Downs, Coulsdon Common or Chipstead Valley and you'll know how narrow and winding they are, and how often you meet walkers, cyclists and horse riders on a blind bend. Add wet leaves and mud in autumn and you have exactly the conditions where ABS and stability control matter most. If a wheel speed sensor has failed, both systems switch off, so a sudden stop on a slippery lane can lock the wheels.
Coulsdon's hills also mean salt and grit in cold weather, and the lanes throw up plenty of mud and water. Sensors live right next to the brakes and hubs, so over the years corrosion builds up around the sensor body and inside the hub where it sits. That can push the sensor slightly away from its ring and weaken the signal, or corrode the connector. The fault often starts as a warning that comes on in wet weather and clears again, before it stays on. On steep hills near Happy Valley Park, drivers may also notice hill-hold has stopped working, as it relies on the same signals.
We read the ABS fault codes, check all four wheel speeds live, and test the circuit to find the real cause. Corroded sensors are often seized, so we take care removing them and clean the mounting properly before fitting the new one, so it sits at the right gap. If the reluctor ring or the bearing encoder is damaged, we'll explain why that part needs replacing too. You get a written quote before any work is done.
From Coulsdon, take Smitham Downs Road west to the A237, then head north through Woodcote and Wallington to Hackbridge, about 4.5 miles. With only the ABS light on, the car is usually fine to drive carefully. Our 3-month workmanship warranty covers the repair.