Electrical faults are among the most time-consuming to trace correctly. Modern vehicles have dozens of electronic control systems, each capable of generating faults that can appear unrelated until you see the live data. At KITH Cars Garage in Hackbridge, we use professional diagnostic equipment that reads manufacturer-specific codes across all control modules before any electrical repair is recommended.
Battery failure accounts for a large proportion of roadside breakdowns, particularly in winter. A battery that starts the car reliably through a warm summer may struggle at minus five degrees when the oil is thick and the starter motor has to work harder. Modern batteries typically last three to five years. Start-stop vehicles cycle their batteries far more often than conventional vehicles, which shortens that lifespan noticeably.
Start-stop vehicles require an AGM (Absorbent Glass Mat) or EFB (Enhanced Flooded Battery) specification. Both are designed to handle frequent cycling. A standard lead-acid battery fitted in error will typically fail within months and the start-stop system will be deactivated by the ECU as a protective measure. We confirm the correct specification for your vehicle before sourcing any replacement.
The alternator test is carried out before we recommend replacement. Correct output is 13.8 to 14.4 volts at charging speed. Below 13.5 volts and the battery is not being properly recharged. Above 14.8 volts and the voltage regulator is at fault. A battery that goes flat repeatedly on a vehicle with a low-mileage, well-maintained battery is usually being undercharged. The alternator should be tested before a second battery is bought.
Glow plugs are the diesel equivalent of spark plugs in terms of their role in cold starting. They heat the combustion chamber so the fuel ignites reliably when the engine is cold. A single failed glow plug causes a rough idle and difficult cold starting. We always replace the complete set because if one has failed at a given age and mileage, the others are typically close. The risk of a glow plug seizing in its bore is worth mentioning on engines with over 100,000 miles. We assess this before quoting and advise accordingly.
ABS sensors and wheel speed sensors are charged at the top rate of £84/hr because they are classified as sensor replacement work. A failed ABS sensor disables the anti-lock braking system and, on most modern vehicles, also takes out the traction control and stability control systems. We read the fault codes first to confirm which corner is affected before removing anything.
