Actron CP7677 Instrucciones de operaciones descargar pdf (Pagina 12)

12

connect RED test lead to negative

side of primary ignition coil. (refer

to vehicle service manual for loca-

tion of ignition coil)

4. Connect BLACK test lead to a good

vehicle ground.

5. Turn multimeter rotary switch to

correct CYLINDER selection.

6. Measure engine RPM while engine

is cranking or running.

7. View reading on display.

• Remember to multiply display read-

ing by 10 to get actual RPM.

If display reads 200, then actual en-

gine RPM is 10 times 200 or 2000

RPM.

Measuring Dwell

Dwell measuring was extremely impor-

tant on breaker point ignition systems of

the past. It referred to the length of time,

in degrees, that the breaker points re-

mained closed, while the camshaft was

rotating. Today’s vehicles use electronic

ignition and dwell is no longer adjust-

able. Another application for dwell is in

testing the mixture control solenoid on

GM feedback carburetors.

To measure Dwell (see Fig. 15):

Ground

Black

Red

Fig. 15

Typical

Ignition

Coil

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 DWELL

signal wire.

• If measuring DWELL on breaker

point ignition systems, connect

RED test lead to negative side of

primary ignition coil. (refer to ve-

hicle service manual for location of

ignition coil)

• If measuring DWELL on GM mix-

ture control solenoids, connect

RED test lead to ground side or

computer driven side of solenoid.

(refer to vehicle service manual for

solenoid location)

• If measuring DWELL on any arbi-

trary ON/OFF device, connect RED

test lead to side of device that is

being switched ON/OFF.

4. Connect BLACK test lead to a good

vehicle ground.

5. Turn multimeter rotary switch to

correct DWELL CYLINDER posi-

tion.

6. View reading on display.

1 2 ... 7 8 9 10 11 12 13 14 15 16 17 ... 33 34

Comentarios a estos manuales

Sin comentarios