Operation Section
-84-
Table a. MI-04 Diagnostic Fault Codes (Flash Codes)
DFC Probable Fault Action Corrective Action, First Check
72 AFRTrimValveLowerDC
FTV duty cycle at lower (lean) limit
Stored Fault Code
(MIL, Disable Adaptive
learns)
Engine measured Air/Fuel ratio at the
O2 sensor is excessively lean.
If LP-Gas fuel in LP tank is not
enough, this fault code can be set. If
LP tank is frozen, this fault code can
be set, too. It is not system trouble.
z Check for intake manifold
leaks
z Check balance line (vacuum
hose) connection at the
regulator
z Check N-CA55-500-TR mixer
for heavy end build-up and
operation (see mixer section)
z Check N2001 secondary for
operation or low primary
pressure (see N2001
Regulator section)
z
73 AFRTrimValveUpperDC
FTV duty cycle at high (rich) limit
(Expected fault when FTV
connector is unplugged)
Stored Fault Code
(MIL, Disable Adaptive
learns)
Engine measured Air/Fuel ratio at the
O2 sensor is excessively rich
Check FTV connector wiring for an
open circuit
z Check N-CA55-500-TR mixer
for heavy end build-up and
operation (see mixer section)
z Check N2001 secondary for
operation (see N2001
Regulator section)
To Next Page
Loading...
Need help?
General
