Toyota 2006 Tundra, Service - Repair - Maintenance

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A23238
AF− AF+
+B
HT SF1ZC−01
A23442
E1
A2A−
A1A+
A1A−
A2A+
Rich
Lean
Time
14.7
3.3
Keep the engine speed
(V)
Air
Fuel
Ratio
A23239
− SFI (1GR−FE) AIR−FUEL RATIO (A/F) SENSOR
SF−63
AIR−FUEL RATIO (A/F) SENSOR
INSPECTION
1. INSPECT AIR FUEL RATIO SENSOR (BANK1, BANK2
AIR FUEL RATIO SENSOR)
Using an ohmmeter, measure the resistance between the ter-
minals.
Resistance:
Terminal No. Resistance
1 (HT)
⇔
2 (+B) 1.8 to 3.4
Ω
at 20 C (68 F)
1 (HT)
⇔
2 (+B) 5.0 to 7.5
Ω
at 500 C (932 F)
1 (HT)
⇔
4 (AF−) No Continuity
If the resistance is not as specified, replace the sensor.
2. INSPECT AIR−FUEL RATIO COMPENSATION SYS-
TEM
(a) Measure the voltage between terminals of the ECM.
Standard voltage:
Terminal No. Condition Voltage
A1A+
⇔
E1 IG switch ON 3.3V
A1A−
⇔
E1 IG switch ON 3.0V
A2A+
⇔
E1 IG switch ON 3.3V
A2A−
⇔
E1 IG switch ON 3.0V
NOTICE:
Connect test leads from the back side of the ECM connec-
tor.
HINT:
The voltage between terminals of the ECM is kept constant re-
gardless of the voltage of the A/F sensor.
(b)
Connect the hand−held tester to the DLC3.
(c) Select ”DATA MONITOR” − ”A/FS B1 S1”, ”A/FS B2 S1”
and ”O2S B1 S2” to display the monitor.
(d) Warm up the A/F sensor by running the engine at 2,500
rpm for approx. 2 minutes.
(e) Keep the engine speed at 2,500 rpm and confirm that the
displays of the ”A/FS B1 S1” and ”A/FS B2 S1” are similar
to the illustration on the left.
NOTICE:
The illustration differs from the real display.
HINT:
The waveform of the A/F sensor is displayed only on the hand−
held tester.
(f)
Confirm that the display of the ”O2S B1 S2” changes be-
tween 0V to 1V with the engine speed at 2,500 rpm.