Toyota 1KZ-TE Repair Manual page 12

BACK TO CHAPTER INDEX
HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS
GENERAL INFORMATION
A large number of ECU controlled systems are used in the HILUX, 4RUNNER and LAND CRUISER/LAND
CRUISER PRADO. In general, the ECU controlled system is considered to be a very intricate system requir-
ing a high level of technical knowledge and expert skill to troubleshoot. However, the fact is that if you pro-
ceed to inspect the circuits one by one, troubleshooting of these systems is not complex. If you have ade-
quate understanding of the system and a basic knowledge of electricity, accurate diagnosis and necessary
repair can be performed to locate and fix the problem. This manual is designed through emphasis of the
above standpoint to help service technicians perform accurate and effective troubleshooting, and is com-
piled for the following major ECU controlled systems:
The troubleshooting procedure and how to make use of it are described on the following pages.
Engine
FOR USING HAND- -HELD TESTER
Before using the tester, the tester's operator manual should be read thoroughly.
S
If the tester cannot communicate with ECU controlled systems when you have connected the cable
S
of the tester to DLC3, turned the ignition switch ON and operated the tester, there is a problem on the
vehicle side or tester side.
(1) If communication is normal when the tester is connected to another vehicle, inspect the diagnosis
data link line (Busline) or ECU power circuit of the vehicle.
(2) If communication is still not possible when the tester is connected to another vehicle, the problem
is probably in the tester itself, so perform the Self Test procedures outline in the Tester Operator's
Manual.
1KZ- -TE ENGINE SUP (RM790E)
INTRODUCTION
System
1KZ-TE
- - HOW TO TROUBLESHOOT ECU CONTROLLED
SYSTEMS
PAGES FROM SUPPLEMENT
BACK TO MODEL INDEX
IN- -9
IN005- -34
Page
DI- -1