KNOVA KN 8056, Manual

Multimeter Basic Testing

7

1. Set the rotary switch to RPMx10.
2. As prompted at the LCD connect terminal,

    insert the red test lead into the      terminal

    and the black one into the COM terminal. Select

    an appropriate number of cylinders. Connect the

   ends to be tested as illustrated.

• If

 a DIS ignition system without any distributor

   board is used in the automobile, connect the red

   test lead probe to the TACH (tachometer) signal

   line (which is connected to the computer DIS

   module of the automotive engine). Refer to the

   automotive servicing manual for the specific

   position.

• If

 an ignition system with a distributor board is

   used in the automobile, connect the red test lead

  probe to the primary negative end of the ignition

  coil. (Refer to the automotive servicing manual for

  the specific position.)
3. Connect the black test lead probe to the good

    ground terminal of the automobile.
4. Upon the start of the engine or during its

    operation, test the rotation speed of the engine

    and read the displayed value from the display.

    The actual rotation speed of the automobile to

    be tested should be equal to the displayed

    value multiplied by 10. For example, the actual 

    rotation speed of the engine of the automobile

    should be 2000 RPM (200 x 10) if the displayed

    value is 200 and the multimeter is set at the

    6CYL (6 cylinders) notch.

Under any testing circumstances, the display of

the meter holds the testing result as soon as the

HOLD is pressed down. When the HOLD is

pressed once more, the testing result held in the

display of the meter will be unlocked immediately

and the meter randomly shows the current testing

result.

Diagnosis of Automotive Troubles

The digital multimeter is a tool for the very effective

diagnosis of the troubles with the electronic

systems of the automobile. This part gives a

special introduction as to how the multimeter is

used to diagnose any trouble with a fuse, switch,

solenoid, relay, starting and charging systems,

ignition system, fuel system and engine sensor.

A. Fuse Testing: Check the fuse to see if it

    is blown out.

1. Set the rotary switch to 200

Ω

.

2. As prompted at the LCD connect terminal,

    insert the red test lead into the 

Ω

 terminal and

    the black one into the COM terminal.
3. Short circuit the red and black test lead probes,

    when the reading of the meter should be

    displayed between 0.2

Ω

 and 0.5

Ω

 If it is more

    than 0.5

Ω

, check the test leads to see whether

    they are well connected.
4. Connect the red and black test lead probes in

    parallel to the two ends of the fuse, when the

    reading of the multimeter should be displayed

H. Data Holding

    less than 10

Ω

, indicating that the fuse is good. 

    When the display is overload “1”, it is shown

    that the fuse has been blown out.

• It must

 be replaced with a fuse of the same type

   and size.

B. Switch Testing: Check the switch to see if 

     it can work correctly.

1. The same as in Items 1 to 3 (Fuse Testing).
2. Connect the black test lead probe to one end

    of the switch and the red one to another end.

    When the switch is connected, the reading of 

    the meter should be displayed less than 10

Ω

.

    When the switch is cut off, overload “1” should

    be displayed as the reading of the meter.

C. Solenoid or Relay Testing

1. The same as in Items 1 to 3 (Fuse Testing).
2. Connect the red and black test lead probes in

    parallel to the two end of a solenoid or relay.

    The impedance of most of solenoids or relay

    coils is less than 200

Ω

.

    (See the details in the automotive manual.)

• Check to see if there is any damaged coil. Even 

   if the coil is found satisfactory, the solenoid or

   relay may still be damaged. The relay may be

   welded or worn due to the frequent sparking of

   the contacts. The solenoid may be stuck when

   the coil is in an on-position. Therefore some

   potential problems cannot be found in testing.

D. Starting/Charging System Testing

The on-off package of the engine starting system

consists of a battery, engine starting button,

solenoid and relay starting buttons, lead

connections and lines. During the operation of the

engine, the charging system keeps the battery 

charged. This system consists of an AC generator,

voltage calibrator, lead connections and circuits. 

The multimeter is an effective tool for the checking

of these systems.
1. Load-Free Battery Testing Before testing the

    starting/charging system, test the battery to see

    if it is fully charged.
   (1) Set the rotary switch to 20 VDC.
   (2) As prompted at the LCD connect terminal,

         insert the red test lead into the V terminal and 

        the black one into the COM terminal.
   (3) Turn off the ignition switch.
   (4) Turn on the driving lights for 10 sec. to

        release charges from the battery.
   (5) Connect the black test lead probe to the

        negative pole of the battery and the red one

        to the positive pole of the battery.

        Measurement Operation(13)
2. The testing results are shown in contrast as

    follows and if the battery is less than 100%,

    please use it after charging it.

          • Both ends of a general solenoid or relay

are connected with diodes.

WARNING