Got some blunt feedback from a master tech about my fuel injector testing

At a Cummins workshop in Portland last month, an old-timer told me I was wasting time using a multimeter instead of a breakout box. I switched to a box on my next 6.7L job and found a voltage drop in 10 minutes that I'd been chasing for an hour. Any of you guys use a breakout box for injector circuits or stick with the meter?

2 comments

2 Comments

thomas_young16d ago

Breakout box is definitely the move for modern common rail stuff, but what nobody talks about is how voltage drop testing itself can be a trap if you don't know the exact specs for that circuit. Multimeter is fine for simple on/off checks but injector drivers use super fast pulses that a basic meter just averages out and misses the real problem. Once you see the waveform on a scope with a breakout box, you're not guessing anymore.

betty_scott1816d ago

Portland? I mean, that old-timer at the Cummins shop really called you out like that? Idk, I'd be a little embarrassed if someone told me I was wasting time with a multimeter after chasing a problem for an hour. Maybe it's just me but a breakout box sounds like a serious upgrade if it cuts the time down that much.