ABS problem - P38

I have a 1995 P38 and its developed a problem with the brakes, but only intermittently.

Sometimes, the abs light stays on the dash and the brakes are hardly there, but other times it works fine - no lights, brakes normal!

I'm not getting any error messages on the computer.

Any ideas?

have you looked for leaks / weeping brake oil anywhere?

More than likely to be the accumulator, or a pressure valve sticking if its imtermitant.

Thanks, we're thinking of trying the accumulator.

A mate has given us the number of someone who can use a fault diagnostic machine on it. Is this worth a try? He wants £50 to plug it in.