I'd like to do a volume test on my injectors, and was thinking that I would activate each one by jumpering it to the battery ( about 15 seconds per injector. ) The thing is that if I understand correctly most injectors run on 5 volts as they are controlled by the ECU and was wondering if activating them like this for short times with the 12 volts from the battery is safe in general and safe for the injectors.

1 Answer 1


Backprobe the injector signal wire and use that to activate the injector. Let the ECM or relay handle the power side of things.

  • Could you explain a little bit more in depth? I have read that some injectors are activated by pulling the second pin to ground. Are you just saying hook the positive side to the ECU connector and then ground the ground side to activate it? Commented Dec 2, 2016 at 12:34
  • @RobertS.Barnes correct, most injectors now adays are grounded to activate. so create an extension if you need one off the injector power source and then you can tap the signal wire to ground.
    – Ben
    Commented Dec 2, 2016 at 12:38
  • 1
    @RobertS.Barnes - Also, when testing injectors, don't allow them to be energized for too long. The "powered on" process creates a bit of heat in the injectors. If left on too long you can damage them. I realize "too long" is subjective, but just keep your energized time to the minimum amount of time to get your testing done. Fuel going through the injectors does help keep them cool, so keep that in mind as well. Commented Dec 2, 2016 at 13:32

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