Suzuki XL7 2007 Service Manual page 267

DTC P2178, 2180, P2188, or P2190
Diagnostic Instructions
• Perform the "Diagnostic System Check - Vehicle
Diagnostic Information: " prior to using this diagnostic
procedure.
• Review "Strategy Based Diagnosis: " for an overview
of the diagnostic approach.
• "Diagnostic Procedure Instructions - Vehicle
Diagnostic Information: " provides an overview of
each diagnostic category.
DTC Descriptors
DTC P2178: Fuel Trim System Rich at Cruise or Accel
Bank 1
DTC P2180: Fuel Trim System Rich at Cruise or Accel
Bank 2
DTC P2188: Fuel Trim System Rich at Idle Bank 1
DTC P2190: Fuel Trim System Rich at Idle Bank 2
Circuit Description
The engine control module (ECM) controls the air/fuel
metering system in order to provide the best possible
combination of driveability, fuel economy, and emission
control. Fuel delivery is controlled differently during
Open and Closed Loop. During Open Loop, the ECM
determines fuel delivery based on sensor signals without
heated oxygen sensor (HO2S) input. During Closed
Loop, the HO2S inputs are added and used by the ECM
to calculate short and long term fuel trim fuel delivery
adjustments. If the HO2S indicate a lean condition, fuel
trim values will be above 0 percent. If the O2S indicate a
rich condition, fuel trim values will be below 0 percent.
Short term fuel trim values change rapidly in response to
the HO2S signals. Long term fuel trim makes coarse
adjustments in order to maintain an air/fuel ratio of
14.7:1.
Conditions for Running the DTC
P2178 or P2180
• Before the ECM can report DTC P2178 or P2180,
failed, DTCs P0008, P0009, P0010, P0011, P0013,
P0014, P0016, P0017, P0018, P0019, P0020, P0021,
P0023, P0024, P0101, P0121, P0122, P0123, P0133,
P0153, P0201, P0202, P0203, P0204, P0205, P0206,
P0221, P0222, P0223, P0261, P0262, P0264, P0265,
P0267, P0268, P0270, P0271, P0273, P0300, P0301,
P0302, P0303, P0304, P0305, P0306, P0335, P0336,
P0338, P0443, P0458, P0459, P0461, P0462, P0463,
P2068 P2088, P2089, P2090, P2091, P2092, P2093,
P2094, and P2095 must run and pass.
• The engine speed is between 1,200-3,400 RPM.
• The mass air flow (MAF) is less than 83 grams/
second.
• The throttle angle is less than 100 percent.
• The engine load is between 17-45 percent.
Engine General Information and Diagnosis:
• The fuel system is in closed loop.
• The engine is not in decel fuel cut-off (DEFCO).
• The long term fuel trim is active.
• The engine coolant temperature (ECT) is greater than
60°C (140°F).
• The intake air temperature (IAT) is less than 61°C
(142°F).
• The evaporative emission (EVAP) canister purge
solenoid valve is not enabled.
• The fuel level is greater than 12 percent.
• The amount of air flow into the engine is greater than
7,000 grams.
• DTC P2178 and P2180 run continuously once the
above conditions are met for at least 300 seconds.
P2188 or P2190
• Before the ECM can report DTC P2188 or P2190,
failed, DTCs P0008, P0009, P0010, P0011, P0013,
P0014, P0016, P0017, P0018, P0019, P0020, P0021,
P0023, P0024, P0101, P0121, P0122, P0123, P0133,
P0153, P0201, P0202, P0203, P0204, P0205, P0206,
P0221, P0222, P0223, P0261, P0262, P0264, P0265,
P0267, P0268, P0270, P0271, P0273, P0300, P0301,
P0302, P0303, P0304, P0305, P0306, P0335, P0336,
P0338, P0443, P0458, P0459, P0461, P0462, P0463,
P2068 P2088, P2089, P2090, P2091, P2092, P2093,
P2094, and P2095 must run and pass.
• The engine speed is between 519-1,001 RPM.
• The engine load is between 7-25 percent.
• The MAF is between 1-7 grams per second.
• The fuel system is in closed loop.
• The engine is not in decel fuel cut-off (DEFCO).
• The long term fuel trim is active.
• The engine coolant temperature (ECT) is greater than
60°C (140°F).
• The intake air temperature (IAT) is less than 61°C
(142°F).
• The evaporative emission (EVAP) canister purge
solenoid valve is not enabled.
• The fuel level is greater than 12 percent.
• The amount of air flow into the engine is greater than
7,000 grams.
• DTC P2188 and P2190 run continuously once the
above conditions are met.
Conditions for Setting the DTC
P2178 or P2180
The Total Fuel Trim Avg. is less than −22 percent. The
condition exists for 4 seconds or for a cumulative of 50
seconds.
P2188 or P2190
The Total Fuel Trim Avg. is less than −40 percent. The
LT FT Idle/Decel is less than −7 percent. The condition
exists for 4 seconds or for a cumulative of 50 seconds.
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