KAL EQUIP KAL 3840 User Manual

Page 57

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1. Connect the capacitive type ignition secondary probe to the CH A input terminal.

2. Connect the Inductive Pickup to the COM/TRIGGER input terminals and connect the COM input of the test tool to

vehicle ground by using a Ground Lead (black) in order to avoid electrical shock before clamping the capacitive
secondary pickup and the inductive pickup on the ignition wires.

NOTE

The Induct ive Pickup must be used to synchronize triggering bet ween the spark
plug wire signal and the coil secondary signal clamped by the capacitive secondary
probe.

3. Clip the secondary probe to the coil secondary lead wire and clamp the pickup probe on the spark plug wire close

to the spark plug.
IMPORTANT : Signals from individual spark plug wires are useful only for triggering. Ignition Peak Voltage, Burn

Voltage, and Burn Time measurements may not be accurate, if the signal is taken on the spark
plug side of the distributor, due to the rotor spark gap. For accurate measurements, use the coil
secondary signal before the distributor.

NOTE

I f you want to test S ECONDA RY IG NI TION SI NGLE , press t o highlight
SINGLE and SECONDARY IGNITION PARADE, press to highlight PARADE.

4. With the Key On, Engine Running (KOER), use the throttle to accelerate and decelerate the engine or drive the

vehicle as needed to make the driveability problem or misfire occur.

5. Make sure that the amplitude, frequency, shape and pulse width are all consistent from cylinder to cylinder. Look

for abnormalities in the section of the waveform that corresponds to specific components.

• Reference Waveform

VEHICLE INFORMATIONS

YEAR

: 1984

MAKE

: Mercedes-Benz

MODEL

: 380 SE

ENGINE

: 3.8 L

FUELSYS : CIS Fuel Injection
PCM_PIN : CH A to the Coil wire
STATUS

: KOER (Key On Running)

RPM

: Idle

ENG_TMP : Operating Temperature
VACUUM : 19.5 In. Hg
MILEAGE : 18575

6-63

Look closely to see that the pulse width (dwell) changes when engine load and RPM
changes.

FIRE = 9.20 kV
BURN = 7.42 V
DUR =2.39 ms
OF CYL 1

arc-over or

ignition voltage

spark or burn

voltage

ign. coil begins

charging here

Burn line

• Symptoms

No or hard starts, stalls, misfires, hesitation, poor fuel economy

• Test Procedure

NOTE

A Capacitive type ignition secondary probe must be used t o t est the ignition
secondary circuit.
Connecting the CH A or CH B leads directly to an ignition secondary circuit can
cause severe damage to the instrument or even personal injury.

Connect the test leads as displayed by the test tool’s HELP (Test Procedure) and shown in Figure below.

6-62

Firing lines should be equal. A short line
indicates low resistance in the wire. A high
line indicates high resistance in the wire

Firing lines clearly displayed
for easy comparison

Available voltage
should be about 10 kV
on a conventional ignition
system and even greater
with an electronic system

Spark lines can be viewed side-by-side
for ease of comparison

Cylinders are displayed in firing order

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