Zenith NA665, Operator'S Manual, Page: 34 / 64

31 Rev-13 Nov 23, 2020
DTC List (continued)
DTC Fault Description
MIL
Flash
Code
831 Fuel pressure sensor signal indicates higher pressure than expected 831
832 Fuel pressure sensor signal indicates lower pressure than expected 832
841
Fuel pressure sensor voltage out of range high, normally set if the pessure
signal wire has become shorted to power or the SECM input circuit has
failed
841
842
Fuel pressure sensor voltage out of range low, normally set if the pessure
signal wire has become shorted to ground, disconnected, or the SECM
input circuit has failed
842
851 Sensor Air Calibration lower limit reached before calibration achieved 851
852 Sensor Air Calibration correction is has adjusted to it's maximum limit 852
853 Sensor Air Calibration upper limit reached before calibration achieved 853
854
Sensor Heater duty cycle lower limit reached and sensor hasn't reached
set point temperature
854
855
Sensor Heater duty cycle upper limit reached and sensor hasn't reached
set point temperature
855
856 Sensor Temperature Set Point not reached after a specified period of time 856
911
Pre-catalyst O2 sensor voltage out of range low, sensor signal shorted to
ground
911
921
Pre-catalyst O2 sensor voltage out of range high, sensor signal shorted to
power
921
951
Trim valve command reached the lower duty cycle limit for the specified
time limit, fuel system is unable to reach the desire PHI setpoint, it could
be rich or lean depending on trim valve configuration
951
961
Trim valve command reached the upper duty cycle limit for the specified
time limit, fuel system is unable to reach the desire PHI setpoint, it could
be rich or lean depending on trim valve configuration
961
991 Service Interval 1 has been reached 991
992 Service Interval 2 has been reached 992
993 Service Interval 3 has been reached 993
994 Service Interval 4 has been reached —time to replace HEGO sensors 994
995 Service Interval 5 has been reached —time to replace engine timing belt 995