AMX:
My 05 Scania R420 has horn and headlights problems. The horn stops working after the truck has been driven for 30 - 40 miles. Full beam on the headlights stops functioning. I have very little knowledge about truck electrics. Any ideas will be appreciated.
Sounds like the horn ring under the steering wheel boss. Its a brass ring with two contacts which are kept in place under spring pressure. It could either be the contacts have worn away or the ring itself has worn through/ cracked. The steering wheel and air bag will have to be removed to check…