Snap-On EETA308D, Reference Manual

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8
Figure 4.
If the vehicle is DIS equipped, current flow through
each coil should be about the same. If the ignition coil
waveform has a sharp rise at the beginning of the ramp
upward, suspect shorted coil windings (refer to Figure 5).
Figure 5.
To measure amperage, measure the maximum voltage of
the waveform and use 100 mV = 1A for calculation.
Tech Note
If the ignition coil is difficult to access, it may be possible
to check the ignition coil current at the fuse box (if
applicable).
To check the ignition coil current at the fuse box:
1. Locate fuse box and remove the ignition or DIS
fuse(s).
2. Install an inline fuse harness in place of the fuse.
3. Clamp the Low Amp Current Probe around the
inline fuse harness.
3.6.4 Injector Current Measurement
Recommended Probe Setting: 20A
Note: Before taking measurements or clamping the
probe jaws around any wire, complete the Setup steps
below.
Setup
1. Use the On/Off and Range Selector switch to select
the 20A setting.
2. Perform the Low Amp Current Probe Zero
Adjustment procedure (refer to section 3.3).