Mazda MX-5 1990 Workshop Manual page 591

OUTLINE
T
OUTLINE
HOW TO USE THIS SECTION
Information regarding removal and installation of electrical equipment is given in SECTION S.
Understanding will be easier if this section is used in conjuncti'on with the WIRING DIAGRAMS.
1.4W or 3.4W
05UOTX-273
69G1SX-003
63U1SX-OOS
ELECTRICAL TROUBLESHOOTING TOOLS
Test Light
9MUOTX-008
The test light, as shown in the figure, uses a 12V bulb. The
two leads should be connected to probes. The test light is used
for simple voltage checks and to check for open circuits.
Caution
• When checking a control unit, never use a bulb over
3.4W.
Jumper Wire
The jumper wire is used for testing by short-circuiting switch
terminals and for verifying the condition of ground connections.
Caution
• Do not connect the jumper wire between a power
source line and body ground because this may
cause burning or other damage to harnesses or
electronic components.
Voltmeter
The DC voltmeter is used for measuring circuit voltage. A volt-
meter with a range of 15V or more is used by connecting the
positive (
+ )
probe (red lead) to the point where voltage is to
be measured and the negative (-) probe (black lead) to the
body ground.
Ohmmeter
The ohmmeter is used to measure the resistance between two
points in a circuit, and is also used to check for continuity and
diagnosis of short circuits.
Caution
• Do not attempt to connect the ohmmeter to any cir-
cuit to which voltage is applied because this may
burn or otherwise damage the ohmmeter.
T-9