Check motor wires are securely terminated.
Check motor fuse (replace with 16/20A slow blow 5x20mm)
Check for loose connections or corrosion on battery terminals
Check the battery condition
SLAVE MOTOR: Check the wiring between the slave and the master motor (S1 and S3). Check for continuity and for short circuit.
Check the motor wires for loose connections.
If a replacement Slave board (CP75A) is available, replace it and try.
Check the contact on the slave motor fuse.
Check if optical counter sensor is properly inserted (casing and the three way plug).
If all the above doesn’t solve the problem, the counter or the CP75 board could be faulty.
MASTER MOTOR: Check the motor wires for loose connections.
Check the contact between the fuse and the fuse holder on the Master motor output channel.
Check if the sensor plug (marked Master Sensor) is inserted properly.
Check if optical counter sensor is properly inserted (casing and the three way plug).
If all the above doesn’t solve the problem, the counter or the CP75 board could be faulty.