Some states have vehicle emission inspection programs which include OBD (On Board Diagnostics) checks. The OBD system monitors the operation of the emission control system.
■ If the malfunction indicator lamp comes on
The OBD system determines that a problem exists somewhere in the emission control system. Your vehicle may not pass the I/ M test and may need to be repaired. Contact your Toyota dealer to service the vehicle.
■ Your vehicle may not pass the I/M test:
● When the battery is disconnected or discharged
Readiness codes that are set during ordinary driving are erased.
Also, depending on your driving habits, the readiness codes may not be completely set.
● When the fuel tank cap is loose
The malfunction indicator lamp comes on as a temporary malfunction and your vehicle may not pass the I/M test.
■ When the malfunction indicator lamp goes off after several driving trips
The error code in the OBD system will not be cleared unless the vehicle is driven 40 or more times.
■ If your vehicle does not pass the I/M test
Contact your Toyota dealer to prepare the vehicle for re-testing.
General maintenanceInspection
INSPECTION
PROCEDURE
1. INSPECT CYLINDER HEAD SUB-ASSEMBLY
(a) Using a precision straightedge and feeler gauge, measure the warpage of the
contact surfaces where the cylinder head contacts the cylinder block sub-assembly
and manifolds.
Text in Illustration
*a
Intake S ...
System Diagram
SYSTEM DIAGRAM
Transmitting ECU (Transmitter)
Receiving ECU
Signal
Communication Method
4 wheel drive control ECU
Skid control ECU (Brake actuator assembly)
High-Low actuator fail
4WD status ...
Check For Intermittent Problems
CHECK FOR INTERMITTENT PROBLEMS
HINT:
Inspect the vehicle ECM using check mode. Intermittent problems are easier to
detect with the Techstream when the ECM is in check mode. In check mode, the ECM
uses 1 trip detection logic, which is more sensitive to malfunctions than normal
mode (default) ...