Toyota 2004 CELICA, Electric Troubleshooting Manual

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2004 CELICA (EWD538U)
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HOW TO USE THIS MANUAL B
This manual provides information on the electrical circuits installed on vehicles by
dividing them into a circuit for each system.
The actual wiring of each system circuit is shown from the point where the power
source is received from the battery as far as each ground point. (All circuit
diagrams are shown with the switches in the OFF position.)
When troubleshooting any problem, first understand the operation of the circuit
where the problem was detected (see System Circuit section), the power source
supplying power to that circuit (see Power Source section), and the ground points
(see Ground Point section). See the System Outline to understand the circuit
operation.
When the circuit operation is understood, begin troubleshooting of the problem
circuit to isolate the cause. Use Relay Location and Electrical Wiring Routing
sections to find each part, junction block and wiring harness connectors, wiring
harness and wiring harness connectors, splice points, and ground points of each
system circuit. Internal wiring for each junction block is also provided for better
understanding of connection within a junction block.
Wiring related to each system is indicated in each system circuit by arrows
(from__, to__). When overall connections are required, see the Overall Electrical
Wiring Diagram at the end of this manual.