The brief
Mr Lim's A6 came in for its routine service, and he mentioned two things: a screeching sound when he stepped on the brake recently, and that he'd had to top up the coolant once in a while. Three jobs in one visit then: the service, the brakes, and the coolant niggle. The screech under braking is the wear-indicator chirp, the front pads worn down to the warning point, and by then the discs have usually reached the end with them. The coolant top-ups point at a slow loss, and the cheapest culprit is the expansion tank pressure cap losing its seal so the system vents a little coolant under heat. So it was the service plus a front brake axle set plus a fresh coolant cap.
The diagnosis
The service check and a brake inspection confirmed it: the front pads worn to the indicator and the discs scored, the calipers fine, the rears with life; and a pressure test on the cooling system showed the expansion tank cap wasn't holding the system pressure, venting too early, which is the slow coolant loss. The rest of the cooling system held fine. The routine service items, oil, filters, fluids, were due alongside. So it was a service plus a front brake axle set plus a coolant cap.
The work
The engine oil and filter were changed, the air and cabin filters replaced, the fluids topped, and a full diagnostic scan run. Both front discs and the worn pads were removed and a new genuine Audi-spec set fitted and bedded in, the calipers serviced. The old coolant cap was replaced with a new genuine cap, the system topped, bled and pressure tested to confirm it now held. A road test confirmed a clean start, steady running, quiet, even front braking with a firm pedal, the screech gone, and the gauge sitting steady with no coolant loss.
The outcome
A clean bill of health on the A6, fresh oil and filters, sharp quiet front braking on a new axle set, the screech gone, the coolant loss sorted, and a clean scan. The car went home serviced and the niggles cleared. Catching the worn brakes and the failing cap during the service caught both before they became roadside problems, so doing it all together kept it to one visit.
