My daughter mentioned that the Corsa was acting strangely when braking. A quick test drive revealed a pulling to the right. Suspecting a lazy front left caliper I whipped the wheel off to check, and found the caliper piston seized.........
Had the Corsa to look at yesterday so I revisited the non-working front left caliper. Undone the flexi to rigid pipe connection and realised I'd mis-diagnosed the problem. No fluid coming from ABS pump to front left caliper. Careless, incomplete diagnoses from me the first time around. 
A quick google and hundreds of posts came up, suggesting that it's a very common fault. So common that the part had to be redesigned to eliminate the flaw. Doesn't look that difficult a job to change, and if the part number matches or you change just the pump part, just a good bleed and away you go.
That's a sign of poor maintenance (lack of brake fluid changes), usually a tap of the ABS module frees the piston, then fresh fluid sorts it
Fluid is very dark and never been changed. That was one of the jobs that I had the car over our house for.

I'd just done the oil and coolant change when they mentioned the brakes.
Interesting about tapping the pump, I did give it a quick couple of taps with a nylon mallet but maybe the shock of a light hammer will do it. Thanks for the tip.

As previously mentioned, the service history on this car is dire, so I have to grab it for inspection whenever I get a chance.
