Komatsu FG25ST-14:
no spark,

serial 581295 This is a 2004 k21 motor, with a no run [no spark from any coil pack) situation. I have no schematic or wire diagrams for this specific (Komatsu, 2004 lpg k21) truck, but have checked the signal wires from the crank and cam sensors back to the ECM, (assuming the ECM inputs are the same pins on other forklift brands with 2004 K21, which they sure do appear to be) and all the fuses and relays I could find. what I don't know is where the other wires in the crank sensor circuit run, (which relay, etc...) if anyone has the schematic for this model series (lpg, coil packs), and any diagrams showing where things may be, and/or a 'legend' for the relays (which one does what), I would sure appreciate the assistance.
Thanks in advance
  • Posted 14 Sep 2014 01:21
  • Discussion started by edward_t
  • South Carolina, United States
"it's not rocket surgery"
Showing items 1 - 3 of 3 results.
Hey, i am currently having the same issue as you, have you found a solution for this issue now 5 years later?
  • Posted 19 Sep 2019 07:41
  • Reply by Jniken
  • Alberta, Canada
Just to update and see if anyone has run into this.
The Accel pedal postion sensor has a 5 volt, and a 2.5 volt leg, I am seeing 5 volts on both legs.
  • Posted 1 Oct 2014 01:19
  • Reply by edward_t
  • South Carolina, United States
"it's not rocket surgery"
just to thank those who tried to help with schematics of other k21 coil pack trucks, and to bump this thread back up, as what I really could use is a diagram or schematic of this particular year and [close] size Komatsu, as Komatsu has a different layout for the relays, and the relays is what I think I need to know is which relay does what.
thanks again.
  • Posted 18 Sep 2014 20:14
  • Reply by edward_t
  • South Carolina, United States
"it's not rocket surgery"

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Fact of the week
Architect Gustave Eiffel originally submitted his design for the Eiffel Tower to Barcelona but the city rejected it for aesthetic reasons. As we know, he had more success in Paris, however, his plan was far from popular at the time.
Fact of the week
Architect Gustave Eiffel originally submitted his design for the Eiffel Tower to Barcelona but the city rejected it for aesthetic reasons. As we know, he had more success in Paris, however, his plan was far from popular at the time.