Other than finding a good used controller I really could only recommend replacing the controller. If you do find a decent used one, make sure it came off a truck that is within the same serial range and with like parameters. I know over here in the states, Warfield Electric offers rebuilts on these controllers at a subtantial savings, dont know if you have access to them over there or not but thats where I get all mine done. I know they beat the oem price by at least 40%.