Description
The ecm constantly generates 5 v power from the battery voltages supplied to the +b (batt) terminal to operate the microprocessor. The ecm also provides this power to the sensors through the vc output circuit.

When the vc circuit is short-circuited, the microprocessor in the ecm and sensors that are supplied with power through the vc circuit are inactivated because the power is not supplied from the vc circuit. Under this condition, the system does not start up and the mil does not illuminate even if the system malfunctions.
Hint:
Under normal conditions, the mil is illuminated for several seconds when the ignition switch is first turned on. The mil goes off when the engine is started.
Wiring diagram

Inspection procedure
Ok: mil lights up












Standard resistance (check for short)


Ecm power source circuit
Fuel pump control circuitAudio settings
Settings are available for adjusting the radio operation, cover
art, etc.
Screen for audio settings
Press the “setup” button.
Select “audio” on the “setup” screen.
Number of radio presets
select the number of radio
preset stations.
Display cover art on/off
Auto ...
Circuit inspection
A description of the main areas of each circuit inspection
is below.
Item
Description
description
The major role, operation of the circuit and its component parts are
explained.
Dtc no., Dtc detection condition, trouble area
Indicates the diagnostic trouble cod ...
Air conditioning control panel does not operate
Description
This circuit consists of the air conditioning control and the air
conditioning amplifier. When the air
conditioning control is operated, signals are transmitted to the air
conditioning amplifier through the lin
communication system.
If the lin communication system malfunctions, ...