hi we have a 1996 toyota hiace campervan and all the warning lights have been appearing at the same time over the last week, specifically the low oil light, radiator light/ handbrake light and the battery light.. we know that we have oil, the radiators fine and the handbrake has no problems either, its been suggested we have a problem with the alternator? Any suggestions what we can do about this as we are in the proccess of selling the van and this doesnt look great!!

Sounds like you have a dead short in the dash wiring harness. Unfortunately you will need to remove the dash clocks and then search for any damage to the wires. Also check the large multi connection blocks on the back of the clocks as there may some corrosion on the connections resulting in a short.