Mazda 1996 626, Руководство по обслуживанию

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FUNDAMENTAL TROUBLESHOOTING
FINDING SHORT CIRCUITS
Shorts occur between the power (positive) and ground (negative) sides of a circuit. Therefore, finding a
short circuit requires determining how the circuit is routed.
Circuits Not Connected to Control Module
Battery
(positive Ignlllon switch
terminal)
Main
(use
Short (fe’
Relay
Fuse
iort(B]i JShort(A)
f " ^3 \ / k 1
\ ......
Short :
(D)
r -
Short(C)
^ __
/ ' --
M o lo r^T O
J
Therm o­
switch
Example
Short location
Short (A)
Short (B)
Short (C)
Short (D)
Indication
Fuse melts.
Main fuse melts.
The motor operates regard­
less of whether the ther­
moswitch is on or off when
the ignition switch is on.
The fuse is not melted.
The main fuse melts when
the ignition switch and ther­
moswitch are on and the
relay is operating.
Finding short circuits
Test light
1. Remove the fuse and
main fuse of the circuit.
2. Disconnect all connec­
tors of electrical compo­
nents in the circuit.
3. Attach a voltmeter or
test light to the fuse box
and reconnect each con­
nector, beginning near­
est the power source.
Check for voltage or see
if the test light turns on
as the connectors are
connected.
A short has occurred where the volt­
meter reads OV or the test light does not
turn on.
Circuits Connected to Control Module
Ignition switch
Fuse
Solenoid
A
Short
( B ) ^
(
^
mi
0
,
1
r - 4 I Sh° n ‘ E>
(D) r l : ;r^L
Switch
A
\ f
Sensor
Example
Short location
Short (A)
Short (B)
Short (C)
Short (D)
Short (E)
Indication
Fuse melts.
Solenoid A operates normally
when the ignition switch is on,
but switch A is off.
The CM transistor burns out
when the ignition switch is
turned on.
The CM thinks the switch is
on because the same condi­
tions exist when the switch is
on.
The CM thinks the sensor has
OQ because the same condi­
tions exist as when there is no
resistance.
If the CM is equipped with a
on-board diagnostic function,
a diagnostic trouble code will
be output.
Finding short circuits
m i
T e s t light
1. Remove the fuse and main
fuse of the circuit.
2. Disconnect ail connectors of
electrical components in the
circuit.
3. Attach a voltmeter or test
light to the fuse box and
reconnect each connector,
beginning nearest the power
source.
4. Check for voltage or see if
the test light turns on as the
connectors are connected.
A short has occurred where the voltmeter
reads OV or the test light does not turn on.
CM
1. Attach the test light or volt­
meter to the CM connector
and switch/sensor connector.
2. Check for voltage or see if
the test light turns on.
A short has occurred where the voltmeter
reads OV or the test light does not turn on.
G I-2 0