Actron AutoTroubleShooter CP7677 - Manual (Page 19)

19
Ignition System Testing
The ignition system is responsible for providing the spark that ignites the fuel in the cylinder.
Ignition system components that the digital multimeter can test are the primary and
secondary ignition coil resistance, spark plug wire resistance, hall effect switches/sensors,
reluctance pick-up coil sensors, and the switching action of the primary ignition coil.
Ignition Coil Testing
This test measures the resistance of the
primary and secondary of an ignition
c o i l . T h i s t e s t c a n b e u s e d f o r
distributorless ignition systems (DIS)
provided the primary and secondary ig-
nition coil terminals are easily acces-
sible.
Test Procedure:
1. If engine is HOT let it COOL down
before proceeding.
2. Disconnect ignition coil from ig-
nition system.
3. Insert BLACK test lead into COM
test lead jack (see Fig. 24).
7. Connect test leads.
• Connect RED test lead to primary
ignition coil positive (+) terminal.
• Connect BLACK test lead to primary
ignition coil negative (-) terminal.
• Refer to vehicle service manual for
location of primary ignition coil ter-
minals.
8. View reading on display.
Subtract test lead resistance found
in Step 6 from above reading.
9. If vehicle is DIS, repeat Steps 7
and 8 for remaining ignition coils.
Typical Cylindrical
Ignition Coil
Black Red
Primary
Coil
Secondary
Coil
Fig. 25
Typical Cylindrical
Ignition Coil
Black
Secondary
Coil
Primary
Coil
Red
4. Insert RED test
l e a d i n t o
test
lead jack.
5. Turn multimeter
rotary switch to
200
Ω
range.
6. Touch RED and
BLACK multim-
e t e r l e a d s t o -
gether and view
reading on dis-
play.
10. Test Results - Pri-
mary Coil
• Typical resistance
range of primary
ignition coils is 0.3
- 2.0
Ω
.
• Refer to vehicle
service manual
for your vehicles
resistance range.
11. Turn multimeter
rotary switch to
200K
Ω
range (see
Fig. 25).
Fig. 24