Here I was screwing around on the net if you haven't found out how yet and this an answer they gave not sure it will work though.
Many Vehicles before OBDII need to be reset with the manufacturers computer/scanner or by shorting terminal jumper locations.
If this vehicle is newer then turn on the ignition to the position before start and press the gas pedal. If dash lights start blinking then press the brake one, two or three times then turn the key back to off and turn back to the position before start. The light should be out. This won't work if you start the vehicle. Sometimes the code is different, exp. Turn on ignition gas, brake, brake, gas. You have to find it
Wednesday, October 16th, 2013 AT 3:45 PM