Actron AutoAnalyzer CP7665 - Manual (Page 9)

9
Fig. 9
2. Insert BLACK test lead into
COM test lead jack.
3. Insert RED test lead into
test lead jack.
4. Turn multimeter rotary switch
to 200
Ω
range.
Touch RED and BLACK multim-
eter leads together and view
reading on display.
Display should read typically
0.2
Ω
to 1.5
Ω
.
If display reading was greater
than 1.5
Ω
, check both ends of
test leads for bad connections.
If bad connections are found,
replace test leads.
5. Connect RED and BLACK test
l e a d s a c r o s s c o m p o n e n t
where you want to measure
resistance.
When making resistance mea-
surements, polarity is not im-
portant. The test leads just have
to be connected across the com-
ponent.
6. Turn multimeter rotary switch
to desired OHM range.
If the approximate resistance is
unknown, start at the largest OHM
range and decrease to the ap-
propriate range as required. (See
Setting the Range on page 6)
Red Black
Unknown
Resistance
1. Insert BLACK test lead into
COM test lead jack.
2. Insert RED test lead into
test lead jack.
3. Connect RED test lead to one
side of voltage source.
4. Connect BLACK test lead to other
side of voltage source.
5. Turn multimeter rotary switch
to desired voltage range.
If the approximate voltage is un-
known, start at the largest voltage
range and decrease to the appro-
priate range as required. (See
Setting the Range on page 6)
6. View reading on display.
NOTE: 200mV = 0.2V
Measuring Resistance
Resistance is measured in electrical
units called ohms (
Ω
). The digital
multimeter can measure resistance
from 0.1
Ω
to 20M
Ω
(or 20,000,000
ohms). Infinite resistance is shown
with a “1” on the left side of display
(See Setting the Range on page 6).
You can use this multimeter to do any
resistance measurement called out
in the vehicle service manual. Test-
ing ignition coils, spark plug wires,
and some engine sensors are com-
mon uses for the OHMS (
Ω
) function.
To measure Resistance (see Fig. 9):
1. Turn circuit power OFF.
To get an accurate resistance
measurement and avoid possible
damage to the digital multimeter
and electrical circuit under test,
turn off all electrical power in the
circuit where the resistance mea-
surement is being taken.