Operator was grading a road, engine died, was able to restart, and died again, towed out of the road and now it is a crank no start. Any information appreciated, thinking it is either fuel supply, oil delivery issue, or electrical malfunction? Cat 140M SN: CAT0140MCB9D02755
Any Codes up on it.? Have you looked at the low pressure fuel system to confirm that at least fuel is getting to the FIP.?
Took a ride down there this afternoon, pulled the fuel line at the engine, no fuel, backtracked to pump no signal from ECM. Plugged into machine, and it is not showing an engine ECM for the C7. Codes for engine ECM, and Data Link, photos atached. Verified power 24volt power at engine power circuit breaker. I was told by operator that the engine circuit breaker popped, and when he reset it he thought he herd snapping in the ECM before it popped the circuit breaker again, I cannot replicate the issue, and the circuit breaker has not popped for me and has power on both sides.
Both you guys have far more experience than I. I did learn this from my limited time with M1 mosheeens... If cranking amperage pulled the voltage too low, it would crank just fine but not have enough voltage to get the PCM to send fuel.
By any chance did you get close enough to the engine ECM to take a whiff of it.? If it has fried something internally then there is a good chance you ought to be able to detect a smell of burned electronics externally. Attached the troubleshooting for both datalinks which should give you some direction. The 590-9 abnormal update rate diagnostic is part of the one for the CDL. There is an attached explanation of the 590-9. If you would like a complete electrical schematic just ask.
My first impression when I opened up the access doors was electrical smell, my plan is to verify power on pins 48/52/53 and key on pin 70. Verify ground on 61,63,65. I have a schematic from Cat, however when I print it the back ground location numbers cover the wiring, if anyone knows how to change that it would be appreciated, our local staples store closed and they knew how to handle this, I asked a buddy to print them and this is what I got back.
It looks like you may have downloaded a schematic in collage form that is designed to print on multiple letter-sized pages then be "stitched" together. Try this one. TBH I always prefer to look at the schematic on a laptop rather than a paper copy.
I am looking over the trouble shooting guides that you sent, looking them over they are for a C9, assuming the protocal would be the same if I have a C7
They were based on your machine Serial Number. AFAIK the C7 and C9 are the same engine family so the procedures should work. If in doubt check wire numbers/colours against the electrical schematic for the machine and use them in preference to the “generic” numbers quoted on the troubleshooting guides. Again AFAIK but the wire numbers & colours for both the CAN and CAT datalinks are the same whatever machine they are installed in.
Thank you very much, I did just that, cross referenced the numbers I had with the schematic. Appreciate the help, machine is dead in the median of the road, so hopefully I am on track for a repair here.
So.....I verified ECM power on pins 48/52/53/55 and key on power pin 70, then ground on pin 61/63/65. I then for fun just ran the Can Data link test and cam back as 125 ohms between the pin 50 and 34, which apparently indicates one of the terminating resistors is missing.
Found part of the problem, ECM definitly toasted, New from Cat $2500 Hopefully this helps someone in the future.
I guess the $64k question now is whether it fried itself due to an internal defect or an external wiring problem. I hope it was the former
Good question, also this is what we found where we believe the CAN network terminating resistor should be.
Should be easy enough to figure out what it is. What are the wire colours coming into the RH side of that 2-pin connector and can you see any numbers on them.? You may have to slide the protective sheath back a bit to find them, should be printed every 6" or so along the wires.
Green and Yellow
Looks like it could be CAN wires. Can you seen F711 and F712 printed on them.?
Nope. Someone has bypassed an A/C pressure switch. Before you go chasing ghosts with your Can network, did you have the batteries isolated when you measured the resistance between pins 50 and 34?
Thanks for the heads up, yes that makes alot of sense. I shut the master switch off before testing the CAN network ohm reading.
They should be here. And here They will manifest themselves disguised as a 3 pin Deutsch blanking plug. Only by close examination shall ye know them, for their posterior sphincter shalt take on the form of crimson india-rubber. A standard blanking plug will have white plastic pins rudely inserted thereupon.
Always when someone shortcuts the system in these computer-controlled Cats, they cause a F##k up down the track. Back 2011 we had a 637G with an intermittently non-operating cushion hitch. The downtime hours & $$$$ spent, trying to isolate the fault over 6 months was unbelievable. I jumped on & drove it for a couple of hours. It worked 75-80% of the time. I told the owner I felt it was an intermittent electrical fault. I removed the panel on the front of the cab where the fuses were & found a wire, the operator had "hot-wired" into the system for a sound system. I disconnected it & ran the wire, fused, direct off a battery. The operator got a "tune up"! We should have "sent him down the road between two suitcases" Problem solved.