Brake shudder!!!

[LJH_89]

I get a brake shudder every now and then but abs light comes on and brakes are perfect. I have put the code reader in and there is no faults showing anybody got any clues what could be causing it

[LJH_89]

Rear brake disc and pads changed a few months ago with fluid and fronts have been an for a while but still enough pad left especially that they are ebc yellow stuff pads. The abs light comes on after about 5 minutes of driving and braking which judder now and then within that 5 mins and like i said before once abs light comes on brakes are perfect just a strange one