Curiosii for ever!: Car repair manuals for everyone.

Oscilloscope Test

INJECTOR

Required Special Tool:
MB991348: Test Harness




Measurement Method
1. Disconnect the injector connector, and connect the test harness special tool MB991348 in between. (All terminals should be connected.)
2. Connect the analyzer special patterns pickup to injector connector terminal 2.

Alternate method test harness not available)


1. Connect the analyzer special patterns pickup to ECM terminal 1. (When checking the number 1 cylinder.)
2. Connect the analyzer special patterns pickup to ECM terminal 14. (When checking the number 2 cylinder.)
3. Connect the analyzer special patterns pickup to ECM terminal 2. (When checking the number 3 cylinder.)
4. Connect the analyzer special patterns pickup to ECM terminal 15. (When checking the number 4 cylinder.)


1. Connect the analyzer special patterns pickup to PCM terminal 1. (When checking the number 1 cylinder.)
2. Connect the analyzer special patterns pickup to PCM terminal 9. (When checking the number 2 cylinder.)
3. Connect the analyzer special patterns pickup to PCM terminal 24. (When checking the number 3 cylinder.)
4. Connect the analyzer special patterns pickup to PCM terminal 2. (When checking the number 4 cylinder.)

Standard Wave Pattern




Observation conditions





Standard Wave Pattern

Wave Pattern Observation Points




Point A: Height of injector coil induced voltage.




Point B: Injector drive time
1. The injector drive time should be synchronized with the scan tool tester display.
2. When the engine is suddenly revved, the drive time will be greatly extended at first, but the drive time will soon return to original length.