ES–3942GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
ES
(e) Select the following menu items on the tester:
DIAGNOSIS / ENHANCED OBD II / DTC INFO /
PENDING CODES.
(f) If no pending DTC is displayed, the repair has been
successfully completed.
OK:
No DTC output.
NG
OKCHECK FOR INTERMITTENT PROBLEMS
END
2GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEMES–397
ES
6. Check that RES RATE B1S1 and RES RATE B2S1 is INCOMPL.
7. Start the engine and warm it up (Procedure "A").
8. Drive the vehicle at between 25 mph and 75 mph (40 km/h and 120 km/h) for 3 minutes. However, the
vehicle should be driven at a constant speed (Procedure "B").
9. Check the monitor result values on the intelligent tester by selecting the following menu items:
DIAGNOSIS / ENHANCED OBD II / MONITOR INFO / MONITOR RESULT /RES RATE B1S1 and
RES RATE B2S1 / Enter.
10. If the values indicated on the tester do not change, perform READINESS MONITOR DRIVE
PATTERN for the A/F sensor and the heated oxygen sensor (See page ES-22).
HINT:
Completion of all A/F sensor monitors is required to change the value in test result.
11. Note the value of the Monitor Result.
12. Select the following menu items: DIAGNOSIS / ENHANCED OBD II / DTC INFO / PENDING CODES.
13. Check if any DTCs (any pending DTCs) are set.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
Related DTCsP2A00: A/F sensor (Bank 1) slow response
P2A03: A/F sensor (Bank 2) slow response
Required Sensors / Components (Main) A/F sensor
Required Sensors / Components (Related) Vehicle speed sensor, Crankshaft position sensor
Frequency of Operation Once per driving cycle
Duration 10 to 15 seconds
MIL Operation 2 driving cycles
Sequence of Operation None
The monitor will run whenever these DTCs are not
presentP0031, P0032, P0051, P0052 (A/F Sensor heater Sensor 1), P0100, P0101, P0102,
P0103 (MAF Sensor), P0110, P0112, P0113 (IAT Sensor), P0115, P0116, P0117,
P0118 (ECT Sensor), P0120, P0121, P0122, P0123, P0220, P0222, P0223, P2135
(TP Sensor), P0125 (Insufficient ECT for Closed Loop), P0171, P0172 (Fuel
System), P0300, P0301, P0302, P0303, P0304, P0305, P0306 (Misfire), P0335
(CKP Sensor), P0340 (CMP Sensor), P0450, P0451, P0452, P0453 (EVAP System),
P0500 (VSS), P2196, P2198 (A/F Sensor (Rationality))
Active A/F control Performing
Active A/F control is performed when the following
conditions are met-
Battery voltage 11 V or more
Engine coolant temperature 75
C (167F) or more
Idle OFF
Engine RPM Less than 4000 rpm
A/F sensor status Activated
Fuel-cut OFF
Engine load 10 to 70%
G034992E04
ES–3982GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
ES
TYPICAL MALFUNCTION THRESHOLDS
MONITOR RESULT
Refer to CHECKING MONITOR STATUS (See page ES-19).
WIRING DIAGRAM
Refer to DTC P2195 (See page ES-359).
INSPECTION PROCEDURE
HINT:
Malfunctioning areas can be identified by performing the A/F CONTROL function provided in the ACTIVE
TEST. The A/F CONTROL function can help to determine whether the Air-Fuel Ratio (A/F) sensor, Heated
Oxygen (HO2) sensor and other potential trouble areas are malfunctioning.
The following instructions describe how to conduct the A/F CONTROL operation using an intelligent
tester.
(a) Connect the intelligent tester to the DLC3.
(b) Start the engine and turn the tester on.
(c) Warm up the engine at an engine speed of 2500 rpm for approximately 90 seconds.
(d) Select the following menu items on the tester: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / A/
F CONTROL.
(e) Perform the A/F CONTROL operation with the engine in an idling condition (press the RIGHT or LEFT
button to change the fuel injection volume).
(f) Monitor the voltage outputs of the A/F and HO2 sensors (AFS B1S1 and O2S B1S2 or AFS B2S1 and
O2S B2S2) displayed on the tester.
HINT:
• The A/F CONTROL operation lowers the fuel injection volume by 12.5% or increases the injection
volume by 25%.
• Each sensor reacts in accordance with increases and decreases in the fuel injection volume.
Standard voltage
NOTICE:
The Air-Fuel Ratio (A/F) sensor has an output delay of a few seconds and the Heated Oxygen
(HO2) sensor has a maximum output delay of approximately 20 seconds.
Shift position 2 or more
Catalyst monitor Not yet
MAF 2.5 to 15 g/s
Response rate deterioration level Less than 0.18 V
Tester Display (Sensor) Injection Volumes Status Voltages
AFS B1S1 or AFS B2S1 (A/F) +25% Rich Less than 3.0
AFS B1S1 or AFS B2S1 (A/F) -12.5% Lean More than 3.35
O2S B1S2 or O2S B2S2 (HO2) +25% Rich More than 0.55
O2S B1S2 or O2S B2S2 (HO2) -12.5% Lean Less than 0.4
2GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEMES–399
ES
– Following the A/F CONTROL procedure enables technicians to check and graph the voltage outputs of
both the A/F and HO2 sensors.
– To display the graph, select the following menu items on the tester: DIAGNOSIS / ENHANCED OBD II
/ ACTIVE TEST / A/F CONTROL / USER DATA / AFS B1S1 and O2S B1S2 or AFS B2S1 and O2S
B2S2. Press the YES button and then the ENTER button. Then press the F4 button.
HINT:
• DTC P2A00 or P2A03 may be also set when the air-fuel ratio is stuck rich or lean.
CaseA/F Sensor (Sensor 1)
Output VoltageHO2 Sensor (Sensor 2)
Output VoltageMain Suspected
Trouble Area
1-
2•A/F sensor
•A/F sensor
heater
•A/F sensor
circuit
3•HO2 sensor
• HO2 sensor
heater
• HO2 sensor
circuit
4• Fuel pressure
• Gas leakage
from exhaust
system
(Air-fuel ratio
extremely lean
or rich)
ES–4002GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
ES
• A low A/F sensor voltage could be caused by a rich air-fuel mixture. Check for conditions that would
cause the engine to run rich.
• A high A/F sensor voltage could be caused by a lean air-fuel mixture. Check for conditions that
would cause the engine to run lean.
• Read freeze frame data using the intelligent tester. The ECM records vehicle and driving condition
information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame
data can be helpful in determining whether the vehicle was running or stopped, whether the engine
was warmed up or not, whether the air-fuel ratio was lean or rich, as well as other data recorded at
the time of a malfunction.
(a) Connect the intelligent tester to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Turn the tester on.
(d) Select the following menu items: DIAGNOSIS /
ENHANCED OBD II / DTC INFO / CURRENT CODES.
(e) Read the DTCs.
Result
HINT:
If any DTCs other than P2A00 or P2A03 are output,
troubleshoot those DTCs first.
B
A
1CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P2A00 AND/OR P2A03)
Display (DTC Output) Proceed to
P2A00 and/or P2A03 A
P2A00 and/or P2A03 and other DTCs B
GO TO DTC CHART (See page ES-56)
