Cat d4g won't move

[Bluetop Man]

The problem is resolved: The steering module went inoperable, locking up all machine track movement. At the same time, the ECM calibrations were apparently erased. Installed new steering module, flashed data to the ECM and re-calibrated. So far, so good. The CAT man had to work on this one, apparently this was an odd failure. Lucky for me, the CAT man discovered the factory installed ECM could reprogram in lieu of a new one, saving $1875 dollars US up front. On the back end, this one took a little longer. Don't know the total damages yet. Thanks to all for their contributions to this thread.

 

[Nige]

Nice to know that it appears to be fixed. None of us here likes suggesting calling the CAT man because we know what it costs simply to get him into his service truck. However sometimes there is no other way.

 

[Seans problems]

Blue top or Nige, I have a D5C lgp and it seems like the parking brake stays on. the light goes off after the dead man switch is pressed. it will try to go forward but locks up and if you try to steer either direction it wont even act like it's trying to engage. Do you guys have any ideas of whats going on?

 

[Nige]

A good start would be a Serial Number.

 

[Seans problems]

Sorry, I'll get the hang of this sometime. 6CS1142 is the serial I have.

 

[Seans problems]

5XK29878, is the serial on this one, model 3046.

Sorry, it was wrong on the list I looked at.

 

[Nige]

First one 6CS1142 is the machine, 5XK29878 is the engine.

When you say "it will try to go forward but locks up", just exactly how far does the tractor move in either the forward or reverse direction before it "locks up"..?
Does it make any nasty noises when it's doing that..?

 

[Seans problems]

The pump engages but is dead headed in forward and reverse. Left or right though the pump doesn’t engage.

 

[Nige]

Do the tracks move at all, even if it’s only just a jerk..?

 

[Seans problems]

They don't move at all.

 

[Nige]

Is the low brake pressure indicator lit..?
It almost sounds as though the parking brake is not releasing even though the indicator light on the panel indicates that it is.
Have you checked the 20A fuse for the brake solenoid and if the fuse is OK, checked the solenoid itself..? The resistance of the solenoid coil is supposed to be 8.15±0.6 ohms.

 

[Seans problems]

The light is not on and I checked the resistance of the solenoid, it's steady at 7.6. That's .7 so I'll start by finding the part number for that. Thank you for your time and help.

 

[Seans problems]

.9 I good math

 

[Nige]

Just because the resistance of the solenoid coil is correct doesn't necessarily mean that the valve it controls is working correctly. That's possibly your next point to check.

Another question. Did the problem start suddenly or has it been slowly getting worse over time until the point at which the tractor won'tr move..?

 

[Shimmy1]

I think you meant to type 0.55?? Which is close, but not out of spec. How fussy are these coils Nige?

 

[Seans problems]

The operator said for the last two months it has been doing this. He called on monday and explained it to me. how do I go about checking the valve it controls?

 

[Nige]

I think you meant to type 0.55?? Which is close, but not out of spec. How fussy are these coils Nige?

Sorry, no idea. But anything that was outside the permitted spec range of 7-55-8.75 ohms would have me changing it. Considering the spec is only around 8 ohms, ±0.6 ohms is almost ±10% so it's a fairly broad range. A lot would depend on the accuracy of the multimeter measuring the resistance I'd guess.

 

[Seans problems]

Okay, Thanks again for the help on this.

 

[Seans problems]

Hey guys, Thanks again for all the help. I bought a handy little DC voltage tester and then put power to the solenoid. The shuttle was only just budging when power was put to it. I swapped the solenoid and the valve because that's how they shipped/sold it to me. for my 2000 d5c-LPG dozer The part number was "160-7203" and the name was "Valve GP brake solenoid".

Thank you and merry Christmas.

 

[Nige]

Good to hear you got it fixed. That 160-7203 Valve is the one that controls the parking brake, if that won't release the tractor's going nowhere fast ..........