Komatsu FG25T-14:
No Fire signal to coil over plug

Hello,

I've got a gas only FG25T-14 and I think nissan k21. (I'm not hovering over it right now to know 100%, maybe 99% sure)

I'm not getting any signal for the coils to fire.

Another mech (from a dealer) came from out of town to take a look at it and we ended up swapping some things. coils, crank and cam sensors, then we swapped out the ecu (thought drivers went out) to no avail. I've checked continuity and resistance and shorts to ground on what seems to be every wire the goes from either plug on the ecu to their termination point. Everthing checked out.

There is 12+ (white/ red stripe- key on) and Ground(Black) but nothing coming in on signal wire (Green) when cranking.

I'm stumped, I would ask for a wiring diagram but there's no need anymore, I think I know where every dang wire goes.


Does anyone have any clue or heard of something similar?

I've got a nice deep hole out back of our shop and I might just loose this lift in it.

yeah...
  • Posted 1 Dec 2020 07:31
  • Modified 1 Dec 2020 07:36 by poster
  • Discussion started by JUTHURA
  • Texas, United States
-J
Showing items 1 - 2 of 2 results.
I have signal from the cam and crank, not getting fire signal to the coil over plug.

I will double check in the sensor hole as well, thank you.
  • Posted 2 Dec 2020 06:01
  • Modified 2 Dec 2020 09:20 by poster
  • Reply by JUTHURA
  • Texas, United States
-J
If you have live and earth to the crank sensor but no signal then you've either got a bad sensor( you've already changed it ) or the sensor isn't seeing a pickup from the crank
Take it out and check the physical pick up that the sensor look for
  • Posted 2 Dec 2020 05:06
  • Reply by Bobble
  • Birmingham, United Kingdom

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