Cummins N14 probelm

[mathura]

Looks as though I am always having some tough issues to deal with. This is a Cummins N14 mounted in a freight liner, called in to look at it, previous techanician claims that it was an injector harness issue, the truck was starting but missing and after he did some work on the harness the engine refuse to start. He ordered another ECM and same probelm.

When checked with insite there is a 254 and 422 active fault codes with both ecm. I tried a third ecm and same probelm, I ran the diagnostics procedures according to T&R manual and found nothing wrong with harness for the 254 code. I even replaced the wire to fuel solenoid but the 254 code remains active and engine would not start.I did not attempt to troubleshoot the 422, what am I missing

Your suggestions please, this is a celect plus ecm.

Need some help here

[je69]

hello dk friends, hi mathura take off tha wire from the fuel solenoide and put a wire wiht a fuse 15 amp from the batery pos to fuel solenoide to make sure tha fuel solenoide its on short if its on short replace tha fuel solenoide, or try to star tha engine god look friend

[mathura]

hello dk friends, hi mathura take off tha wire from the fuel solenoide and put a wire wiht a fuse 15 amp from the batery pos to fuel solenoide to make sure tha fuel solenoide its on short if its on short replace tha fuel solenoide, or try to star tha engine god look friend

I even tried a bypass to the solenoid by removing the ecm wire from it and supplying it with another power but no luck.

[Poptest]

Check if other loads are connected to the solenoid terminal and /or to pin 16 of actuator harness.

Check solenoid resistance and check if positive terminal is short circuit to ground.... replace solenoid if bad.

[mathura]

Check if other loads are connected to the solenoid terminal and /or to pin 16 of actuator harness.

Check solenoid resistance and check if positive terminal is short circuit to ground.... replace solenoid if bad.

Checked for other loads on pin 16 and it is supplying only solenoid, even replaced the wire from pin 16 to the solenoid.
The solenoid resistance is 14ohms with no signs of shorting to ground.

Checked all pins on actuator plug to see if it is shorting to pin 16 and this proves ok.

I am not sure what next to do at this time.

[pbateman]

Hey Dk friends been a day or so. Mathura i ran into this issue once and I found that the wiring on the coolant sensor plug was reversed. Don't know if this will help but you may check there. Also I would look at the data link back bone there is usally a resistor in the harness should be 120 ohms. It almost sounds like to me there is a ground issue and the thing there is being able to find it. I'm not all that familiar with the freightliner wiring as we deal with petes and kw's. so my friend hope this helps I know what your going through freightliners are a pain when it comes to their wiring.

[pbateman]

mathura forgot to mention the 422 is the coolant sensor and the only reason I found this out was someone had changed the plug at one time and reversed all the wires. so this may be causing your issue with the fuel solenoid. just a thought. hope this info helps also.

[mathura]

mathura forgot to mention the 422 is the coolant sensor and the only reason I found this out was someone had changed the plug at one time and reversed all the wires. so this may be causing your issue with the fuel solenoid. just a thought. hope this info helps also.

Thanks pbateman
At least I now have something to work with, I was planning on getting rid of the coolant level fault and then see what happens
I will let you know my findings

Thanks again

[MoShCaKe]

Mathura did you beat that problem?

I had that problem before aswell, with both fuel sol.

just completely replaced unswitched power supply from batteries to ECM and never had the problem again

[mathura]

Mathura did you beat that problem?

I had that problem before aswell, with both fuel sol.

just completely replaced unswitched power supply from batteries to ECM and never had the problem again

Did not get time to visit the job its some distance away, will let you know how it goes. Thanks for sharing your expierence MoShcake