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650J halts going over bumps

Browfurrow83

Active Member
Joined
Feb 26, 2024
Messages
32
Location
Ontario
Serial 109143
Speeds in the mid 2s the crawler briefly comes to a stop--throwing the operator forward or back--happens more often in reverse when going faster--and resumes with no code.
New TCU relay<it would not move at all with a CAN failure code this error was here before that but it has gotten worse since
Both tracks affected it still goes straight
Parking brake switch checks out it seems that it would make you cycle to neutral to resume when I tested it
Transmission filter light when starting goes out when it warms up it was a cold day
Does anything about this jump out at anybody?
 

mg2361

Senior Member
Joined
Jul 5, 2016
Messages
6,790
Location
Pennsylvania
Occupation
Equipment Mechanic
and resumes with no code
You checked this on the TCU itself, and not the monitor, correct?

Sounds like a wiring issue and that the jolt of the bump is breaking a connection.

Try turning the anti-stall off. If the issue goes away check the engine speed sensing circuit/wiring. If the issue remains, maybe run separate power and ground wires to the TCU to see if that resolves the issue.
 

Steve Austin

Senior Member
Joined
Nov 27, 2016
Messages
412
Location
Tullahoma TN
Had this problem years ago machine would come to an abrupt sudden stop. Inspect the wiring harness under the floor plate. Do not remember the exact location there was a very small bare spot in the harness contacting ground at times. Inspect carefully where harness may be laying against pump housing brackets ETC. It only takes a very very small bare spot to kill the 5 volt power to the sensors.
 

Browfurrow83

Active Member
Joined
Feb 26, 2024
Messages
32
Location
Ontario
You checked this on the TCU itself, and not the monitor, correct?

Sounds like a wiring issue and that the jolt of the bump is breaking a connection.

Try turning the anti-stall off. If the issue goes away check the engine speed sensing circuit/wiring. If the issue remains, maybe run separate power and ground wires to the TCU to see if that resolves the issue.
Go a chance to go back for a while today.
TCU had codes of
F3P5
FP93
F393
F3X1
F359
AI'd these nothing really jumped out from the results
Ran a Jumper from the large wires in the fuse panel to a back-probe at the red wire in the leftmost plug of TCU did 2 laps around field without detecting the same problem at up to 3 speed. Tried the same running from wire P12 at the fuse panel did not have the same but it is hard to know if the back-probe is making good contact
 

Browfurrow83

Active Member
Joined
Feb 26, 2024
Messages
32
Location
Ontario
Does it have a seat safety switch that would affect it if interrupted?? Maybe needs a fatter operator?
And on that note, I have had more than one machine with cab/rops mounts shot and the cab sat a little lower crushing the harness.
They look Ok I am not seeing pinching. A white wire V-something-maybe 07 that goes to the fuse panel has been replaced because it rubbed through on the floor pan.
 
Last edited:

Browfurrow83

Active Member
Joined
Feb 26, 2024
Messages
32
Location
Ontario
Had to leave today. I plan when I get back to continue to trace P12 wire back from the 10 amp fuse--because bypassing P12 did not seem to work--12V power did seem to work. The laps around the field without failure could have been a fluke so confirm that power works I guess.
 

Browfurrow83

Active Member
Joined
Feb 26, 2024
Messages
32
Location
Ontario
Did pop the cover off of the TCU clean dry and unburnt in there cleaned ground-strap to fender

CAN Measures 120 ohm with the TCU end terminating resistor unplugged likewise at the engine end. 60 ohm back-probing with both in.
You checked this on the TCU itself, and not the monitor, correct?

Sounds like a wiring issue and that the jolt of the bump is breaking a connection.

Try turning the anti-stall off. If the issue goes away check the engine speed sensing circuit/wiring. If the issue remains, maybe run separate power and ground wires to the TCU to see if that resolves the issue.
I was checking the wrong one.
 

mg2361

Senior Member
Joined
Jul 5, 2016
Messages
6,790
Location
Pennsylvania
Occupation
Equipment Mechanic
The F3P5 might be an issue. F393 would be related. Both of which could be related to an intermittent electrical connection.

Check your messages.
 
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