Service manual

G420F(FE) Service Manual Chapter 9. Advanced Diagnostics 286
Table 1. Fault List Definitions (cont’d.)
FAULT DESCRIPTION
CODE
(MI04 CODE)
LiqPostO2Inactive
Post-catalyst O2 sensor control on gasoline has sensed the
O2 sensor is not responding as expected. If any Pre-O2
sensor faults are set, diagnose these first and after correcting
these faults recheck if this fault sets. Possible causes for this
fault are sensor disconnected, sensor heater failed, sensor
element failed, heater relay, or SECM control of heater relay
is disconnected or failed.
842
Reserved 843
LowOilPressureFault Low engine oil pressure
521
(52)
MAPRangeHigh
Manifold Absolute Pressure Sensor Input is High, normally set
if the TMAP pressure signal wire has become shorted to
power, shorted to the IAT signal, the TMAP has failed or the
SECM has failed.
342
MAPRangeLow
Manifold Absolute Pressure Sensor Input is Low, normally set
if the TMAP pressure signal wire has been disconnected or
shorted to ground or the circuit has opened to the SECM
332
MAPTimeRangeHigh
Manifold Absolute Pressure Sensor Input is High, normally set
if the TMAP pressure signal wire has become shorted to
power, shorted to the IAT signal, the TMAP has failed or the
SECM has failed
341
(34)
MAPTimeRangeLow
Manifold Absolute Pressure Sensor Input is Low, normally set
if the TMAP pressure signal wire has been disconnected or
shorted to ground or the circuit has opened to the SECM
331
(33)
MAP_IR_HI MAP sensor indicates higher pressure than expected 351
MAP_IR_LO MAP sensor indicates lower pressure than expected 352
MAP_STICKING MAP sensor not changing as expected 353
MediumOverspeed
Engine speed has exceeded the second level (2 of 3) of
overspeed protection
572
O2RangeHigh
Pre -catalyst O2 sensor voltage out of range high, sensor
signal shorted to power
921
O2RangeLow
Pre-catalyst O2 sensor voltage out of range low, sensor signal
shorted to ground
911
O2_PostCatRangeHigh
Post-catalyst O2 sensor voltage out of range high, sensor
signal shorted to voltage source (5V or battery)
922
O2_PostCatRangeLow
Post -catalyst O2 sensor voltage out of range low, sensor
signal shorted to ground
912
SensVoltRangeHigh Sensor reference voltage XDRP too high
561
(56)