Actron Advance Timing Light CP7528 - Manual (Page 11)

MEASURING ENGINE RPM
(Digital Timing Light Only)
1. Press and Release Button Until RPM Indicator Lights.
If engine is not running or #1 spark plug is not firing, timing light
display will flash, indicating that no signal is being received.
Always follow test procedures in vehicle service manual or Vehicle
Emission Control Information Label. Instructions given here are for
reference only.
IMPORTANT
10