I suggest you look in the fuse box, the most common problem with these 4300{or any volvo loader of that vintage} was someone that knows nothing of electronic s putting little Black square fuse in incorrect position, this Happened quite frequently in Volvo loaders, The operator sitting idle waiting for trucks to load so he has poke about c ab opens fuse box pulls this little black thing out and then doesnt remember what hole it c ame from, so goodness the truc ks arrive back so he pokes it in any where, cause he doesnt rem ber where it came from and LO he haS NO REVERSE OR NO FORWARD so Boss calls Volvo service that service is about 5 hours away the fitter arrives put little black thingo back in correct position the operator of course denys any knowledge of tampering with the fuse box and may i say this was a common problem when Volvo were first sold in Australia and New Zealand hope this is all your problem is
