1-3

What This Code Means

Carbon Monoxide Monitor CO above limit; Input voltage below normal range (for CO monitor); Battery voltage above normal operating range; Battery voltage below normal operating range; No voltage drop detected between relays and ECM-3L with relay on (Fuel Pump & Field Boost Relay); Open or short to ground between relays and ECM-3L (Fuel Pump & Field Boost Relay); Oxygen Sensor output voltage above normal range; Oxygen Sensor Heater circuit shorted to battery; Oxygen Sensor output voltage below normal range; Oxygen Sensor Heater circuit open or shorted to ground; No voltage drop detected between Injector 1-A and ECM-3H (Fuel Injector - Cylinder 1); No voltage on injector low side (ECM-3H) (Fuel Injector - Cylinder 1); No voltage drop detected between Injector 2-A and ECM-2H (Fuel Injector - Cylinder 2); No voltage on injector low side (ECM-2H) (Fuel Injector - Cylinder 2); Engine still running lean; Short-term Fuel Trim Exceeded maximum fuel correction (added fuel)