Engine Running Quick Test

1. Start and run engine to stable idle. Upper radiator hose should be hot and pressurized. Carburetor should be off high cam.
2. Turn ignition off. Connect a jumper wire from Self-Test Input (STI) to Pin 2. See Fig 1 .
   Fig 1: Meter Hook-Up for Reading Codes

   
3. Set analog VOM on a DC voltage range to read from 0 to 15 volts DC. Connect VOM from battery positive post to Pin 4 Self-Test Output (STO) in the Self-Test Connector.
4. Start and run engine to stable idle. Upper radiator hose should be hot and pressurized. Carburetor should be off high cam. Activate self-test.
5. Observe and record all service codes. Service codes are transmitted to the Self-Test Output terminal in the form of timed pulses. On the analog meter each pulse equals 1 meter sweep.
   • One-half second on-time pulse for each digit.
   • Two seconds off-time between digits.
   • Four seconds off-time between codes.
   • Eight to twelve seconds before fast and service codes.

Example: 6 pulses (sweeps) equals digit 6; two second pause then 8 pulses (sweeps) equals digit 8, this will equal code 68.