Hi, I’m in the process of restoring a ‘88 model classic, but am having some difficulty getting the brake modulator/abs master cylinder to work correctly. The unit is a Wabco ntc5921.
The red abs light will not go out and under heavy braking the vehicle pulls violently to the right!
Is this a serviceable unit?
If so, can anyone recommend a service company.
TIA for any suggestions.
Mike

Clearly there is an ABS fault. Your first move has to be getting the blink codes from the ecu. Once you know why the red light is on you can then troubleshoot the system.

If pulling to the right, check all the calipers (front and back) are working correctly. Sticking pistons are a common problem. It may also be the case there is air in the system so a full bleed is indicated as being necessary. A pressure bleeder is the way to go!

If the master cylinder/modulator/booster unit is faulty it is not serviceable and MUST be replaced.

You say yours is a 1988? ABS wasn't available for that model year AFAIK it was an option from October 1989 and standard on Vogue SE from that date.
Good luck.

Hi classic Kev, many thanks for your reply.
Will check those points out.
Vehicle is on an H plate but code is GA.... First regd. 1/8/90
Sorry, should have mentioned it is a Vogue 3.9
Mike

1990 makes more sense. It can be a minefield. Mine is an HA Vogue SE on a '91 J plate but that was a change over year so some bits are 1990MY, for example, the swivels, other bits are 1991 on.

Good luck with it, the ABS can be, well, errrmmmm, challenging. Once it is working fine and no warning light LEAVE IT ALONE! Do check the blink codes and make sure you properly clear the ABS ECU as it can store multiple codes.