Diesel Cold Advance System Check: Notes

With ignition on voltage is supplied to cold advance relay through 20-amp GAUGES fuse. When coolant temperature is less than 80°F (27°C), as sensed by coolant temperature sensor, ECM provides a ground at terminal C6. See Figure. Grounding terminal C6 energizes cold advance relay, closing relay contacts and supplying 12 volts to cold advance solenoid (in injection pump), and glow plug controller. Cold advance solenoid is now energized, causing injection pump timing to be advanced about 4 degrees.