seat toledo 1.9 tdi 90 km 96-99 year I have a similar problem with ABS, error 1276 Hydraulikpumpe ABS-V64 - signal outside the limit value, while driving, when the engine warms up, ABS lights up, when it cools down the next day, it's calm until warm up the engine, about 40 km must be driven for the engine compartment to warm up well,
I dismantled the pump, I washed the valves and what I could, no effect, today I dismantled the ABS controller it was hard to split it glued to some sealants I struggled not to damage the controller housing too much, I probably found the cause, I gently removed the silicone protecting the board from moisture I found cold solder joints at the output for the ABS pump motor, this plug with two round pins in the picture, I corrected these February and a few others that I didn't like, I varnished it with a special plastic spray for printed circuit boards to protect against moisture and overvoltages (spray plastic about PLN 40 in electronics stores), tomorrow I will install the controller and in a few days I will let you know if it worked as soon as I go somewhere else to warm up the engine compartment well, here is a photo of the controller the pump was in the car (you have to move)
