Ignition Coil Primary
2017 Chevrolet Silverado 1500 · 5.3L V8 EcoTec3 L83
Sensor Type
inductive
Waveform Type
dc-variable
Location
Individual coil-on-plug assemblies mounted directly on each spark plug, top of cylinder heads
Pins
2-pin connector
Idle Frequency
16.67 Hz
Timebase
10ms/div
Voltage Scale
50V/div
Trigger
12V, falling edge
Wiring
Pink/Black (ignition feed from fuse), Gray or specific cylinder control wire (PCM driver)
Expected Voltage Range
At Idle
0V to 14V
At Higher RPM
0V to 14V
Expected Pattern
Initial 14V battery voltage, drops to near 0V during dwell (coil saturation), sharp spike to 200-350V at coil cut-off, followed by damped oscillations before returning to battery voltage
Known-Good Waveform
Clean square dwell period of 2-4ms at idle with battery voltage dropping cleanly to near 0V, followed by sharp inductive kick to 200-350V lasting 1-2ms with 3-5 damped oscillations. Current limiting should show flat bottom during dwell period indicating proper coil saturation.
Common Failure Patterns
Low voltage spike under 150V or extended dwell time over 6ms
Cause: Weak or failing coil with increased resistance, reduced inductance
Erratic dwell time or missing firing events
Cause: Failed PCM coil driver transistor or corroded connector at coil
Diagnostic Tips
L83 EcoTec3 coils are known for internal breakdown causing misfires under load. Compare dwell time and voltage spike across all 8 cylinders - they should be within 10% of each other. Check for oil contamination in spark plug wells which damages coil boots.
Related Diagnostic Trouble Codes
P0351P0352P0353P0354
Always confirm waveform data with your vehicle's OEM service manual before diagnosing.
Free, no signup. View all waveforms for this vehicle