INDEX
Cover Page
Index
Safety Information
Specifications
Meter Identification
Basic Tests
Setting Range Position
AC/DC Voltage
Measuring DC Amps/Milliamps
Continuity Open Circuit Test
Diode Test
Engine RPM
Measuring Dwell
Battery/Starting/Charging
No Load Battery Test
Cranking Battery Load Test
Finding Excessive Current Draw
Charging System Voltage
Engine Sensors Tests
Throttle/EGR Valve Position, Air Flow
Manifold Absolute Pres. MAP Sensor
Barometric Pressure BARO Sensor
Oxygen Position Sensor
O2 Sensor Circuit
SAFETY INFORMATION
WARNING!
To avoid possible electric shock or personal injury, and
to avoid possible damage to the Meter or to the
equipment under test, adhere to the following rules:
1. Before using the Meter inspect the case. Do not
use the Meter if it is damaged or the case (or part of the
case) is removed. Look for cracks or missing plastic.
Pay attention to the insulation around the connectors.
2. Inspect the test leads for damaged insulation or
exposed metal. Check the test leads for continuity.
3. Do not apply more than the rated voltage, as
marked on the Meter, between the terminals or
between any terminal and grounding.
4. The rotary switch should be placed in the right
position and no any changeover of range shall be
made during measurement is conducted to prevent
damage of the Meter.
5. When the Meter working at an effective voltage
over 60V in DC or 30V rms in AC, special care should
be taken for there is danger of electric shock.
6. Use the proper terminals, function, and range for
your measurements.
7. Do not use or store the Meter in an environment of
high temperature, humidity, explosive, inflammable and
strong magnetic field. The performance of the Meter
pg. 1
Mass Air Flow MAF Sensor
pg. 2
pg. 3
pg. 3
Fuse/Switch/Solenoid Tests
pg. 3
Fuses/Switches
pg. 3
pg. 3
Ignition System Tests
pg. 3
Distributor Cap/Rotor Resistance
pg. 3
Variable Reluctance Sensor
pg. 4
Crankshaft Timing Sensor
pg. 4
pg. 4
Ignition Coil
pg. 4
pg. 5
Ignition Wires
Fuel System Tests
pg. 5
pg. 5
C3 Meter Control Solenoid
pg. 5
pg. 5
Injector Test
pg. 5
Injector Wiring Harness Test
pg. 6
pg. 6
Maintenance & Troubleshooting
pg. 6
Overrange Indication
pg. 6
Zero Adjustment
pg. 6
Automatic Polarity
pg. 7
Alligator Clip Adapters
pg. 7
Low Battery
pg. 8
Battery Replacement
pg. 8
Fuse Replacement
pg. 8
may deteriorate after dampened.
8. When using the test leads, keep your fingers
behind the finger guards.
9. Replace the battery as soon as the battery
indicator appears. With a low battery, the Meter
might produce false readings that can lead to electric
shock and personal injury.
10. Remove the connection between the testing leads
and the circuit being tested, and turn the Meter power
off before opening the Meter case.
11. When servicing the Meter, use only the same
model number or identical electrical specifications
replacement parts.
12. The internal circuit of the Meter shall not be altered
at will to avoid damage of the Meter and any accident.
13. Soft cloth and mild detergent should be used to clean
the surface of the Meter when servicing. No abrasive and
solvent should be used to prevent the surface of the
Meter from corrosion, damage and accident.
14. The Meter is suitable for indoor use.
15. Turn the Meter power off when it is not in use and
take out the battery when not using for a long time.
Constantly check the battery as it may leak when it has
been using for some time, replace the battery as soon as
leaking appears. A leaking battery will damage the Meter.
pg. 9
pg. 9
pg. 10
pg. 10
pg. 10
pg. 11
pg. 11
pg. 11
pg. 11
pg. 11
pg. 12
pg. 12
pg. 13
pg. 13
pg. 13
pg. 13
pg. 14
pg. 14
pg. 14
pg. 15
pg. 15
pg. 15
pg. 15
pg. 15
pg. 15
pg. 15
pg. 15
pg. 16
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