CAT 259D - No Crank E459-2 Code

[Simon C]

While you are messing around with that C903 wire on Pins 3 & 23 you could also try proving all the powers and grounds to the Engine ECM. I see a total of 9 power wires and 7 grounds on connector J1 and I suggest that you need to check every one of them.

Totally agree as just one insufficient strength ground or positive power could end communication or more. Was wondering if @ Johnkorpita how was the computer ground tested back to the Battery Negative post and how much was the reading. Most manufacturers want less than 0.100 Millivolt loss from computer grounds to Battery Negative with big problems starting to happen by 0.300 Millivolts. Was there current flowing when this was tested. ( This is what Fluke has on their website that I printed a long ways back )
Post #55 Hunterdan had to have the computer changed but that is last effort after forsure testing all that Nige mentioned.
How much loss was there from the Battery positive to all the positve feeds of the Engine ECM is what needs to be ruled out now also. These will be higher as the voltage is in the 14 volt ballpark when running, but how much is viewed as too much is probably in the 0.5 to 0.7 volt range of loss from battery positive to ECM positives.
Interested to see what comes of these tests.
Simon C

 

[Johnkorpita]

So I checked on the schematic everything that you posted here, you did not mention Conn#23 where the power passes through to go to connector #5 Pin #27. You did mention that you tested it all the way through to the Engine ECM Power Relay Pin #86 so if that wire had current going through it would appear to be okay.
Only thing that sticks out that has not been checked is the ARC Suppressor that Nige mentioned above.

Simon C

I visually inspected connector 23 and also backprobed it and it was good. I did run power through the connector from one end to the other and it was okay.

Arc suppressor changed swapped with the other one and no change.

Good idea Nige, I will test all those powers and grounds. It may be a challenge to unpin the pins given how hard it is to get both hands on the connector in the tight workspace. Will do these tests this afternoon.

 

[Nige]

It may be a challenge to unpin the pins given how hard it is to get both hands on the connector in the tight workspace.

You may require a Deutsch connector unpinning tool or two to remove those wires.

 

[Johnkorpita]

You may require a Deutsch connector unpinning tool or two to remove those wires.

Problem Solved. btw, the harness that goes into the ECU is a molex from what i learned...so a little different than the Deutsch.

I feel slightly dumb...because it ended up being a fuse.

When i tested all the positives and grounds in the J1 Connector, the grounds were all good but there were some inconsistent and questionable things in the positive pins.

pin 1- 12v
pin 12-4.6v
pin 13-0 v
pin 33-0 v
pin 38-12v
pin 58-12v
pin 78-12v

This lead me to go backwards to find any possible fail points. As i traced the wire series 123 from pins 13 and 33 it finally lead me back to the fuse box in the cab. I pulled out the 15 amp fuse and it looked good on the eyeball test...but it failed an actual test. I replaced it and that was my problem all along. I thought i checked all those fuses...but apparently not well enough. As we all get older i suppose the eyeball test is less and less accurate and should probably be discontinued for me at this point.

Thank you so much Nige and Simon for your advice and guidance. I basically took the extremely long way around to find a bad fuse...I learned a lot along the way and hope this helps someone in the future. I have the schematic just about memorized. LOL.

I circled the fuse that failed in the attached picture.

 

[Nige]

Kudos to you for fessing up and glad that you are up and running again. On the way I'm sure you learned a good deal about your machine electronic system.

Remember that the man who never made a mistake never made anything..........

 

[Simon C]

Problem Solved. btw, the harness that goes into the ECU is a molex from what i learned...so a little different than the Deutsch.

I feel slightly dumb...because it ended up being a fuse.

When i tested all the positives and grounds in the J1 Connector, the grounds were all good but there were some inconsistent and questionable things in the positive pins.

pin 1- 12v
pin 12-4.6v
pin 13-0 v
pin 33-0 v
pin 38-12v
pin 58-12v
pin 78-12v

This lead me to go backwards to find any possible fail points. As i traced the wire series 123 from pins 13 and 33 it finally lead me back to the fuse box in the cab. I pulled out the 15 amp fuse and it looked good on the eyeball test...but it failed an actual test. I replaced it and that was my problem all along. I thought i checked all those fuses...but apparently not well enough. As we all get older i suppose the eyeball test is less and less accurate and should probably be discontinued for me at this point.

Thank you so much Nige and Simon for your advice and guidance. I basically took the extremely long way around to find a bad fuse...I learned a lot along the way and hope this helps someone in the future. I have the schematic just about memorized. LOL.

I circled the fuse that failed in the attached picture.

Glad you did not buy a computer for the blown fuse, I once was caught with a blown fuse that was good enough for a multimeter but would not run a test light. Thanks for sharing.
Simon C

 

[smifwal]

I would bet you check fuses and relays first next time something funny happens.

I just had a no crank moment with my 2021 259 and I am out of the cat warranty only have power train and hydraulic through the dealer. I was sitting right on top of the trench and had to use the head so I shut the machine off since I had to go to the outhouse. Jump back in turn the key to on wait for the beep turn to start nothing, no codes or warning lights. Checked every fuse (both sides, I have learned that is important lol) with the dummy light (didn't have the multi meter) check the relays swapped them around, even checked the magnet on the arm rest switch to see if it was still magnetized no Joy. Called a couple of the techs I know, no answer, broke down and called the field service manager to see if there was anything else I could do. He dispatched a guy and I kept tinkering, I unhooked the connector of the arm bar safety and it threw a code for that plugged it back in, code went away,I tried to start it again and boom we are back up and running, called him back and told to him to recall the tech and what he thought happened. He said that it was a fluke. There has always been a moment before it cranks and now everytime I start the machine their is that knot in my tummy that it won't start

 

[Simon C]

I would bet you check fuses and relays first next time something funny happens.

I just had a no crank moment with my 2021 259 and I am out of the cat warranty only have power train and hydraulic through the dealer. I was sitting right on top of the trench and had to use the head so I shut the machine off since I had to go to the outhouse. Jump back in turn the key to on wait for the beep turn to start nothing, no codes or warning lights. Checked every fuse (both sides, I have learned that is important lol) with the dummy light (didn't have the multi meter) check the relays swapped them around, even checked the magnet on the arm rest switch to see if it was still magnetized no Joy. Called a couple of the techs I know, no answer, broke down and called the field service manager to see if there was anything else I could do. He dispatched a guy and I kept tinkering, I unhooked the connector of the arm bar safety and it threw a code for that plugged it back in, code went away,I tried to start it again and boom we are back up and running, called him back and told to him to recall the tech and what he thought happened. He said that it was a fluke. There has always been a moment before it cranks and now everytime I start the machine their is that knot in my tummy that it won't start

Arm rest safety can be checked by unplugging the harness and running a 5 amp test bulb through the loop to see if the wiring is in satisfactory condition to handle the load. If something is weak it will manifest itself when under load. If it dies again post your serial number for someone to be able to see the exact wiring for it.
Simon C