2001 TOYOTA SEQUOIA Service Repair Manual

refrigerant type trip computer open hood air conditioning open gas tank window

Page 657 of 4323

TOYOTA SEQUOIA 2001 Service Repair Manual +25 %
±12.5 %
More than 3.35 V
Less than 3.0 V
1
A/F Sensor (Sensor 1)
Output Voltage
Injection volume
Output voltage
HO2 Sensor (Sensor 2)
Output VoltageMain Suspected
Trouble Areas
OK
+25 %
±12

+25 %
±12.5 %
More than 3.35 V
Less than 3.0 V
1
A/F Sensor (Sensor 1)
Output Voltage
Injection volume
Output voltage
HO2 Sensor (Sensor 2)
Output VoltageMain Suspected
Trouble Areas
OK
+25 %
±12.5 %
More than 3.35 V
Less than 3.0V
Injection volume
Output voltage
+25 %
±12.5 %
More than 0.55 V
Less than 0.4V
Injection volume
Output voltage
A/F sensor+25 %
±12.5 %
More than 0.55 V
Less than 0.4V
Injection volume
Output voltage
+25 %
±12.5 %
Injection volume
Output voltage
NG
+25 %
±12.5 %
Injection volume
Output voltage
NG
+25 %
±12.5 %
Injection volume
Output voltage
NG
+25 %
±12.5 %
Injection volume
Output voltage
NG OK
OK
OK
Almost
no reaction
'
Almost
no reaction Almost
no reaction
Almost
no reaction
Case
2
3
4
A/F sensor circuit A/F sensor heater
HO2 sensor
HO2 sensor circuit HO2 sensor heater
(Air±fuel ratio extremely
lean or rich)Injector
Gas leakage from
exhaust system Fuel pressure
± DIAGNOSTICSENGINE
DI±455
649 Author: Date:
2005 SEQUOIA (RM1146U)
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.
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, and press the YES but-
ton and then the ENTER button followed by the F4 button.
HINT:
DTC P2A00 may be also set, when the air±fuel ratio is stuck rich or lean.
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 a hand±held tester or OBD II scan tool. Freeze frame data record the
engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help
determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air±fuel
ratio was lean or rich, and other data, from the time the malfunction occurred.

Page 658 of 4323

TOYOTA SEQUOIA 2001 Service Repair Manual B17396
HT +B
AF± AF+ Sensor 1A/F Sensor Component Side:
Front View
DI±456
± DIAGNOSTICSENGINE
650 Author: Date:
2005 SEQUOIA (RM1146U)
1 Check any other DTCs output (in addition to DTC P2A00 or

Page 659 of 4323

TOYOTA SEQUOIA 2001 Service Repair Manual A23659
Wire Harness Side:
HT
A38
Sensor 1A/F Sensor Connector
AF+
Front ViewAF±
+B A39
B17415A55007
E7ECM Connector
HA1A
A1A+
A1A±
A2A+
A2A±HA2A
A23512
Reference (Bank 1 Sensor 1 System Drawing):
A

Page 660 of 4323

TOYOTA SEQUOIA 2001 Service Repair Manual DI±458
± DIAGNOSTICSENGINE
652 Author: Date:
2005 SEQUOIA (RM1146U)
NG Replace or replace harness or connector.
OK
4 Perform confirmation driving pattern.
NEXT
5 Check whether DTC output recurs

Page 661 of 4323

TOYOTA SEQUOIA 2001 Service Repair Manual ± DIAGNOSTICSENGINE
DI±459
653 Author: Date:
2005 SEQUOIA (RM1146U)
8 Check whether DTC output recurs (DTC P2A00 or P2A03)
CHECK:
(a) On the hand±held tester, select the following menu items: D

Page 662 of 4323

TOYOTA SEQUOIA 2001 Service Repair Manual 0.02 inch orifice clogged
Pressure sensor low outputP043E
P043FP0441 P0451 P0452 P0453 P0455 P0456 P2419P2401
P2402
0.02 inch orifice high±flow
Pressure sensor stuck
Pressure sensor noise
Gross leak

Page 663 of 4323

TOYOTA SEQUOIA 2001 Service Repair Manual A23474
Purge VSV
(Vacuum Switching Valve)
EVAP Hose
(To Throttle Body)
EVAP Hose
(From Canister) Location of EVAP (Evaporative Emission) system:Vent ValveCanister
Pressure Sensor
Vacuum Pump
Purge Li

Page 664 of 4323

TOYOTA SEQUOIA 2001 Service Repair Manual A23669
EVAP Purge Flow:
Canister Purge VSV
(ON)
Vacuum Pump (OFF)Air Filter Fuel Tank fuel tank cap
To Intake Manifold
Pump Module
Pressure Sensor0.02 Inch Orifice
Vent Valve (OFF)
ECM
Soak Timer
Refu

A23669
EVAP Purge Flow:
Canister Purge VSV
(ON)
Vacuum Pump (OFF)Air Filter Fuel Tank fuel tank cap
To Intake Manifold
Pump Module
Pressure Sensor0.02 Inch Orifice
Vent Valve (OFF)
ECM
Soak Timer
Refueling Valve
To Atmosphere
DI±462
± DIAGNOSTICSENGINE
656 Author: Date:
2005 SEQUOIA (RM1146U)
Key±off monitor
This monitor checks for EVAP (Evaporative Emission) system leaks and pump module malfunctions. The
monitor starts 5 hours*
after the ignition switch is turned OFF. More than 5 hours are required to allow enough
time for the fuel to cool down to stabilize the Fuel Tank Pressure (FTP), thus making the EVAP system moni-
tor more accurate.
The electric vacuum pump creates negative pressure (vacuum) in the EVAP system and the pressure is
measured. Finally, the ECM monitors for leaks from the EVAP system, and malfunctions in both the pump
module and purge VSV, based on the EVAP pressure.
HINT:
*:If the engine coolant temperature is not below 35C 5 hours after the ignition switch is turned off, the moni-
tor check starts 2 hours later. If it is still not below 35C 7 hours after the ignition switch is turned off, the
monitor check starts 2.5 hours later.
Purge flow monitor
The purge flow monitor consists of the two monitors. The 1st monitor is always conducted every time and
the 2nd monitor is activated if necessary.
The 1st monitor
While the engine is running and the purge VSV (Vacuum Switching Valve) is ON (open), the ECM
monitors the purge flow by measuring the EVAP pressure change. If negative pressure is not
created, the ECM begins the 2nd monitor.
The 2nd monitor
The vent valve is turned ON (closed) and the EVAP pressure is then measured. If the variation
in the pressure is less than 0.5 kpa (3.75 mmHg), the ECM interprets this as the purge VSV being
stuck closed, and illuminates the MIL and sets DTC P0441 (2 trip detection logic).
Atmospheric pressure check:
In order to ensure reliable malfunction detection, the variation between the atmospheric pressures, before
and after conduction of the purge flow monitor, is measured by the ECM.

Load next 8 pages

Page: < prev 1-10 ... 625-632 633-640 641-648 649-656 657-664 665-672 673-680 681-688 689-696 ... 4328 next >

fuel additives weight hood release snow chains immobilizer length