Roy already explained the coherences between ABS and transmission ECU.

Especially if there is no automatically disengagement or flashing warning lamp of the ABS, check the sensor rings at the rear outer drive shaft joints. Possibly one is loose or cracked.

Read out ECU. Recorded faults, meaning implausible wheel speeds also point to a sensor ring problem. Another option are rusty speed sensor plugs. Defective wheel speed sensors should appear as defined malfunction.

Beste Grüße
Tim