Sensors lead the way in warranty claim

Posted on October 29th, 2018 by Rob Marshall

Sensors lead the way in warranty claim

A report that says sensors have pipped alternators to become a top warranty claim (for those sold by the RAC dealer network) came as little surprise to us, when the news hit GEM’s technical helpdesk.

There are several reasons for this, such as virtually everything mechanical being influenced, or controlled, entirely by electronics that depend on some kind of sensor to feed back information, in order to keep the vehicle running. Should there be a fault with the sensor, or crucially, its wiring, or anything associated with the circuit, the car might either stop running, or a malfunction indicator light may appear on the fascia.

Not only do sensors but also wiring and connections degrade over time, not helped when faced with the vibrations and wide temperature variations experienced within the hostile environment of a motorcar.


Misdiagnosis mistakes

Yet, while sensors have become the most popular warranty claim in this survey, do not imagine that they are the most unreliable car part. While I shall discuss the importance of a garage being given sufficient opportunity to make an accurate diagnosis in a future blog, sensors tend to be blamed for causing faults, when the real root lies elsewhere. A faulty connector, a bad earth, a damaged ECU, or simply an inexperienced technician, can also be to blame.

For example, in 2016, the Engineering Aerospace and Automotive Faculty of the

Exeter College Technology Centre intercepted discarded engine sensors that had been replaced by a host of garages. After testing the sensors, over half of them were found to be working. Therefore, in all of those cases, garage customers had paid for having sensors replaced that was unnecessary. Even so, blaming sensors for being at fault, when they are not, is an issue that I hear at least several times a week.