My ageing 2000 Sonata has an issue with the brake light indicator, after starting engine and driving perhaps 200 yards the warning light will come on.

Replaced brake pads not long ago, not long after light started to come on.

I then noticed I was constantly low on brake fluid, and saw a stain on driveway from the rear near-side brake, upon inspection determined it was the caliper (seal had gone), which I've replaced and stopped the leak & fluid levels remain the same BUT the light remains on?

No leak from other 3 calipers, pads are fine. etc

Any suggestions?

Thanks!

 

Did you bleed the entire system after fixing the leak? My guess is there is still air in the system. Or the master itself is going bad.

 

Thanks for the reply

I did yes, only on that caliper, do I need to bleed all 4 in order or something?

What do you mean by the master?

 

Yes, whenever you open it you need to bleed the entire system. And always bleed the caliper/wheel cylinder furthest from the master first, moving closer to the master. Basically, Right rear, left rear, right front, left front. Stopping to fill the master between each caliper/wheel cylinder.

By "master" I mean the Master Cylinder.

 

Not if you do it right. Set the pedal and block it (e.g. with a piece of wood btw seat and pedal), remove the caliper and install replacement part. All you need to bleed is the part of the system you had opened then (bleed with the pedal released).

Anyway I would like to ask what brake warning ligt precisely goes off (on) here, fluid level light (if that exists) or the ABS light ?
Fluid level would not become low after driving 200yd and be back fine at next engine start. That sounds like typical ABS fault detection.

The coincidence of pad change and light problem coming up is suspicious, too. Maybe wiring damage, wheel speed sensor contamination with metal dust are possible in this context.