I have installed a SC400 92 in another car and need to be able to read the diagnostic codes from the ODB1. How can i get the diagnostic codes when i don't have the original instrument board ?
Use a 12v bulb and apply 12v to one side and a wire from the 'W' wire (See diagram below) at the ECU to the other side, then just bridge terminals TE1 and E1 in the diagnostics port and switch on ignition. You can now count the flashes the same as you would with the dash check light.