Ignition Coil Test

Ignition Coil And Power Transistor Harness Inspection:

INSPECTION USING SCAN TOOL

Ignition Coil And Power Transistor:

Ignition Coil And Power Transistor Waveforms:

Wave Pattern Inspection Using an Analyzer
- Ignition coil primary signal
- [1][2]Ignition power transistor control signal

Measurement method
1. Disconnect the [1][2]ignition power transistor connector, and connect the special tool (test harness: MB991348) in between. (All terminals should be connected.)
2. Connect the analyzer special patterns pickup to [1][2]ignition power transistor unit connector terminal.

Alternate method (test harness not available)
1. Connect analyzer special patterns pickup to ECM terminals 10 for [1][2]ignition power transistor.

Examples of abnormal wave patterns

Example 1
Wave pattern during engine cranking

Cause of problem
Open-circuit in ignition primary circuit

Wave pattern characteristics
Top-right part of the build-up section cannot be seen, and voltage value is approximately 2V too low.

Example 2
Wave pattern during engine cranking

Cause of problem
Malfunction in [1][2]ignition power transistor

Wave pattern characteristics
Power voltage results when the [1][2]ignition power transistor is ON.