have you been able to clear the code with the pedal dance, at all? (with this code, should be able to clear the code, even if you have not fixed the problem, and not have it return until you turn the motor over at least 2 revolutions, so until you hit the starter, the code would be cleared, returning after the crank sensor sees #1 cylinder 2 times or the cam sensor sees each of it's cylinders twice).

what is the valve lash clearance? would it be contributing to the 27 code? thanks

I have seen some that have an ODBII connector under the dash. That is also a possibility.

getting your hands on this program won't happen unless you are a dealer tech.
as for clearing the code there are 3 ways you can try to do it
-call a dealer tech to come out and clear it for you
-try the pedal dance trick
-unhook the battery for 30 mins or more

if the code persists then there is still a problem that needs to be resolved.

OK edward t and rcav8ter and swoop. how can i get my hands on the computer programing on all these mit,cat,ni, ko, yale and hy. W/O BEING AN OEM. I'M an independent. plz. help.

search this site's forum archive for "pedal dance", you will find the instructions on clearing codes without the laptop, on these trucks.
you may have set the "major code" function, but it will clear with the pedal dance, as long as what ever set the code is fixed, AND the code is not related to a foot pedal's operation.
You are correct about the seat switch, (especially if it can go in forward or reverse gear, without someone on the seat).

yes dash lights are flashing. hour meter flashing hours and code e-27. how to reset w/o computer. or is something else wrong? by the way the seat switch is unhooked but hydraulics work when not on seat. must be cross wired some where?

If the dash lights are still flashing then it is an active code. Are the hrs being displayed followed by the e-27?

OK STATUS update. i called the customer just to make sure problem hadn't solved it's self nope still problem. so he allowed me a 3hr. window to repair. on the phone. so i drove there, found #4 and #3 coil packs arcing out at the head of each pack. so now unit has 4ct new coil packs. runs like it should except still flashing code 27 and dash lights are flashing off and on. then customer comes out and says closing early today. i just looked at him with those **** off mechanic eyes. and said i'll be back to get code off. i tried the pedal dance and my obd2 reader codes wont clear any ideas? i also removed each coil pack wires to see if it changed operation each one did.

I would also check the valve lash as the unit has 6500 hrs and original plugs. Possible tight valve. With 6500 hrs, this tells me the maintanence on this unit was an oil change and grease its whole life.

My bad guys. hours are 6287. and the had original plugs.

if another coil pack has gone bad, I would try and convince the customer to go for the full set, as this is most likely a high hour truck that had not had the spark plugs changed for very many hours.
These crank and cam sensors, are they new or from a good running k21-k25 motor? these days, I would want to test them in a truck that ran before I trusted them for a 120 mile each way drive. just lately, I have seen a truck that ran OK but had a crank sensor that set a cam sensor error about 1 time in every 20 or 30 starts. it did not have any effect on the operation and it became a historical code the next start cycle.

Check cranks sensor pins and make sure one has not been bent when reconnected. The plug should be fine.

OK so I'm taking 4 CT COIL packs. 4ct. Nissan Spark plugs. 22401-FU42A. ONE Cam sensor. One crank sensor. if another coil is bad should i replace all 3 used coil packs. a plug isn't going to go bad in 2 days is it.?

I second what edward stated.