ELBOW 3N8769 - Caterpillar

MID 036 CID 1086 FMI 09Conditions Which Generate This Code:The oxygen buffer has been powered for at least 60 seconds. The duty cycle for the oxygen signal is between 10 and 20 percent. The 1088 - 06 Oxygen Sensor Power Supply short to ground diagnostic code is not active.System Response:Compensation for fuel quality is disabled. The diagnostic code remains active until the duty cycle of the oxygen sensor is greater than 20 percent for at least five seconds.The alarm output is activated. The code is logged.Possible Performance Effect:Engine performance and emissions may be affected.Troubleshooting:A duty cycle of 10 to 20 percent is the default output when a load for the heater of the oxygen sensor is not detected by the oxygen buffer. In this case, check for one of the following conditions:
Disconnected oxygen sensor
Burned out heater for the oxygen sensorTest Step 1. Perform the following diagnostic procedure: "Oxygen Sensor Signal"Results:
OK - STOP