I have a D3G XL and the hydrostatic drive will only move the machine at a very very slow creep unless the throttle is wide open. The throttle or speed selector wont make any difference in speed until you give it full throttle. Once at full throttle the machine works perfectly. My local cat dealer said it could be a bad parking brake switch or the parking brake valve. I changed both and it has made no difference in how the machine operates. It has plenty of power even when it is only creeping I drove it into our loading dock and the tracks just started very slowly digging holes no problem. I also tried to see if there are any codes in the computer but i cannot retrieve any. I connected wire 1 with wire 2 in the black diagnostic connector and nothing happened at all. I was told by a member here that if you connect those 2 wires for a second it should flash the codes through a light in the dash. Anyone have any ideas?
I think your machine is okay. Hystats need full throttle to move, you control speed with drive pump. It should have a throttle cable down to a valve that will slow travel when you throttle down to prevent stalling the engine. Later Bob
Bob, these transmissions can be programmed by techs to do different things like making reverse a percentage of forward travel speed (like 150% for example) or limiting the top speeds (one tractor may have a top speed of 6.8 mph while another may have a top speed of only 4 mph depending on owner preference). He's got something wrong going on with it, cause mine would move at an engine speed barely above idle. Also, there's no mechanical governering of pump as it's all controlled by the machine's computer. If you're in a speed that's too high for the load, the computer automatically destrokes the pump until the load is reduced and then it speeds back up, like a torque converter drive would.
does it change speed when you increase the speed with your left thumb switch? does the gage respond?
The serial number is cat00d3gljmh02016. The speed does not increase with the left thumb switch unless the throttle is wide open. The gauge does respond at low rpm but the rest of the machine does not.
Pulling the codes should be the first step. let us know what codes you find. (2) Harness Code Connector (3) Service Tool Connector (ET) (4) Diagnostic Indicator The service tool connector and the harness code connector are located behind the access cover for the fuse panel. The access cover is above the cab floor on the left side of the machine To enter service mode, disconnect the machine identification plug from the harness code connector. When the control module is in the service mode the control module's diagnostics are available in order to assist with troubleshooting. A single diagnostic code is shown. The diagnostic code is on hold. Information is shown on the diagnostic indicator by flashing the indicator ON and OFF. The flashes represent a three digit number. A series of flashes represent the first digit. A one second pause follows the first digit. Another series of flashes represents the second digit. A one second pause follows the second digit. Another series of flashes represents the third digit. Count the number of flashes. The number of flashes determine each digit. A three second pause separates each three digit number. Use table 2 in order to find the correct CID. When you scroll through the diagnostic codes, the codes for all of the active diagnostic codes are shown one at a time. Ground connector contact 1 in order to scroll through the active diagnostic codes. Remove the ground from connector contact 1 in order to stop scrolling. The diagnostic code that is shown is now on hold. A code of 222 indicates that diagnostic codes are NOT active or logged. Perform the procedure that corresponds to the diagnostic codes. Clearing a diagnostic code removes the diagnostic code from the control module's memory. When a problem is corrected, it is necessary to remove the diagnostic code from the memory of the control module. The diagnostic code must be on hold in order to clear an inactive diagnostic code. The control module does not allow active diagnostic codes to be cleared. Place the diagnostic code on hold. The diagnostic code is on hold. Ground connector contact 3 in order to remove the logged diagnostic code from the control module's memory. The diagnostic indicator is extinguished after the inactive diagnostic code has been cleared. The diagnostic indicator is extinguished until you scroll through the diagnostic codes. The control module does not allow active diagnostic codes to be cleared. Repeat the procedure for any remaining diagnostic codes. Return to normal mode when you are finished by replacing the machine identification plug. A diagnostic code of 222 indicates that diagnostic codes are NOT active or logged.
Okay Don, that machine is more modern than I have worked on. Last I had much to do with had a throttle link to allow limited pump output for travel without stalling at low throttle. Computer can do more. Later Bob
Ok i was able to get the codes out, I was looking at the wrong light before. The codes are 254, 252, 244, 271, and 141. Thanks for all the help guys.
So your codes are ........ 254 (CID 1693) - Decelerator Pedal Position Sensor 252 (CID 0468) - Service Brake Pedal Position Sensor 244 (CID 0070) - Parking Brake Rocker Switch 271 (CID 1706) - Proportional Solenoid (Reverse Right Drive Pump) 141 (CID 0190) - Engine Speed Sensor Have you tried erasing them one at a time just to see if any of them are inactive..? You might be lucky and find you only have 1 or 2 active codes out of the 5 you listed.
Some are prolly old so clear them all out and see what comes back.
I will try erasing them in the morning thanks so much everyone. Should I erase one and run the machine and see if it comes back? Or should I erase them all and run it and see what comes back?
Just erase them all. If you have an active code it cannot be erased.
Try erasing each one in the order you bring it up (so first one first in other words). I'm sure you will find that some of these codes are old ones that once erased will not come back, at least not in the short term. You cannot delete a code that is Active. Erase as many as you can at one hit, you won't need to run the machine. Erasing whatever you can will leave you with a short list of codes that will not erase. These are the ones you will have to troubleshoot and fix. Once each one is fixed you can then erase it using the same procedure as before. Fixing whatever is causing the codes is most likely to be the answer to your no-drive problem.
I was able to erase all the codes the only code I have now is 222. I ran the machine a little and I am still having the same problem. I did notice that if i play with the decelerator pedal the machine will work as it should at times. Can the decelerator pedal sensor cause this problem. I checked the codes again after I ran it and i still have just 222. Should i run it more and see if the codes come back?
222 indicates you have no Active Codes, which is good news, so you have no "bad" sensors. You might still have a sensor that's out of adjustment though. My first thought would be blast the area around the pedal pivots (there are a million bushes in there, or so it seems looking at the Parts Manual) with WD40 or similar, just in case something is hanging up somewhere. Second thought would be to test the decel pedal sensor & adjust if necessary, the problem is you need Cat ET to do that unless Lee knows a way to do it without. Does the engine speed fall to between 800-900 RPM when you press the declerator pedal..? Plus I would re-do the adjustment procedure for the brake limit switch if adjusting the decel pedal sensor doesn't fix the problem. I'll e-mail you the procedures.
I do not know what the rpm is the machine does not have a tach.
All the code you had could be the cause. Some times a problems need to be seen by the ECM for a period of time before it logs the code. Recalibrating is a good idea but you have to use ET. I have fixed these machine with calibrating the joystick. Have no idea why it lost its calibration. A calibration is a good troubleshooting procedure and a machine tune up. if the speed sensor is reading incorrect, a low RPM then the ECM will destroke the drive pumps because it thinks there is too much load. Remove and clean the speed sensor. Reinstall until it touches the flywheel, then back off 1/2 turn. Its in the flywheel housing on the left side.
Just found this. Track-Type Tractor: D3G (S/N: JMH1-UP) D4G (S/N: FDC1-UP; HYD1-UP; TLX1-UP) D5G (S/N: WGB1-UP; RKG1-UP) Issues with the 189-5746 Speed Sensor Gp. The debris at the tip of the sensor can affect the signal from the sensor. The debris is caused by contact with the starter gear and the flywheel gear. The debris can accumulate at the tip of the sensor. Remove the 189-5746 Speed Sensor Gp from the engine and clean the tip of the sensor. The sensor should be checked after 1,000 hours of operation. Reinstall the sensor. Check the connection of the connector and the harness for any damage if the problem still exists. If damage is found then replace the speed sensor with a new speed sensor. (1) 189-5746 Speed Sensor Gp
Ok I am going to clean the speed sensor today, I will let you know how it works out. Thanks again for all the help.
Remember that as Lee says above, make sure to set the clearance correctly when you re-fit it by turning it until it touches the flywheel, then back out 1/2 a turn and lock the locknut.
I removed the cps sensor and the end was covered in metal shavings. I cleaned it and reinstalled it till it touched the flywheel and backed it out 1/2 turn and tightened the lock nut. The machine still acts the same way it did before. I still feel like it has something to do with the decel pedal. Seems like if it is in just the right position that the hydro will work properly. Then if you move the decel pedal slightly the hydro will slow down even though the engine rpm went up. Looks like the boss either has to buy me the cat et software or let cat come fix it.
ET software & hardware will be out of your league, believe me ....... It looks like the only option is to get a dealer service guy out to calibrate the decel pedal sensor. While he's there have him calibrate all the sensors that can be calibrated. Have you lubricated the pedal mechanism as suggested a few posts back..?
Why would you say the et programs are out of my league. I have run a lot of diagnostic equipment on cars and smaller trucks plenty. Is the cat program much different? I did lube the little linkage between the decel pedal and the sensor.
My apologies, I was referring to price & value for money (vs a technician visit) if you only have a single machine that it can be used on. The ET Communications Adpater (hardware) that is required to connect a PC to the machine via the Diagnostic Port retails at around $1500-$2000 depending on which type you purchase. To buy the ET software plus a 12-month licence so that it can be used on a single PC is about the same. If you only have 1 or 2 machines then $3000-4000 for your first year of using the ET diagnostic tool makes it pretty expensive. You can get quite a few service visits from a dealer guy for that type of money.
Lee, now what about the speed sensors on the final drives? One of mine started leaking under warranty. I was talking to the tech when he replaced it and said sometimes they go out and make the machine do funny stuff. I think he said they had to calibrate them to make the machine track straight. I think you have to take the rear belly pan off to access them, but I don't remember them being very hard to get to. Maybe just a little access plate at the rear? As far as getting the Cat dealer to repair it, take it to their shop. Their travel and service call rates should be against the law. I am only being serious...
Well I have finally had some time to devote to this machine again. I still feel that the problem is in the decel pedal sensor but i cannot prove it. I took the machine to cat and showed the mechanic what it was doing. Then they call a few days later and say there is nothing wrong with the machine we can come pick it up. I went there and showed another mechanic what it is doing and he said he has never seen one do that. They said there are no codes in the computer so they don't know what to fix. They said the only thing they can do is start throwing parts at it but that it will get expensive. Is there any cat tech service that I can call and get them to tell my cat dealer what to do? The service manager was trying to tell me that if it was a sensor that it would show a code because they done just lose calibration they are either good or bad. I know they don't really know what they are doing and in the end it is gonna cost me money for them to learn on my machine.
Ask the dealer Service Mananger to have his Technical Communicator submit a request in the Caterpillar DSN system describing the problem symptoms and listing everything that has been done to the machine so far (like cleaning/adjusting the sensor for example). This system is a storehouse of information from all over the world, cross your fingers that someone else somewhere in the world has had the same problem at sometime and called for help. Whatever the solution to the problem was the info regarding the fix will be in the DSN Database. I just got a fix today on an Cat 854K from DSN and the answer to my question came back in less than 4 hours because another machine somewhere had done the same thing and the fix was there in DSN. All we had to do was apply it.
Pull the sensor one more time to check for metal fragments (it only takes a jit to throw this off) and peek in at the hall effect rotor. Make sure it is not coated with gunk, mud or rust. Good luck. Ron
I worked on a D4G half a year ago, same simptoms and problems. Went through all the calibrations, tests and so on. Nothing fixed it. I ended up swapping the decel pedal sensor with one I had it my toolbox, and it solved the problem. Not saying its going to solve yours but it may be worth a shot.
I can not do any more work to it now because it is at the cat dealer now. I will let you guys know how I make out with it if I can ever get them to call me back. I have left messages and they dont return phone calls they were supposed to call me monday with what they found but that didnt happen. Thanks for all the help.
Thank you all for the help cat finally fixed it and I picked it up yesterday and it seems to be working fine now. They said the recalibrated everything and now it works as it should. They would not tell me what specifically was out of calibration but either way it is working now.
Hey nige having same problem would like procedure for brake limit switch
I'm having what seems like the same problem with a D3G I just bought. Cleaned the flywheel sensor today and no change. 06 model with 3700hr s/n BYR01487 Any thoughts?
Try pulling the Diagnostic Codes on it. See post #6 on page 1 for the "how to". Report back what you find.
Will do, Thanks
124 241 244 246 251 252 254 261 Here are the codes that showed up. Is there any codes #124? The only one that seemed odd but that is what I thought it showed.
After reading through this post again, I see where I need to clear all of the code I can. I will clear out what I can in the morning. And post what I find. Do I need to run it after I clear the codes or just start it up? To see what comes back.
There are two types of Code, Active & Logged. Active is there right now, Logged was there once but is not there now. Logged Codes you can clear, Active ones you cannot clear until you fix them (which turns them into Logged). You should not need to start up or run the machine after clearing the Logged Codes, simply turn the key on. Then re-check the remaining codes that are showing and ensure that they are all Active. You may need to re-check the 241 because it is not on the Code List....... Everything else that you have corresponds to the drive system one way or another.
Ok cleared out the codes, and now all I get is the 222 code. Meaning no active codes right? Is it necessary to place the plug back on the test point to check for more codes?
No. The fact that you have 222 indicates that there are no Codes in the Monitor. If you want to double check you can refit the Harness Code Plug, turn off the Master Switch for a few minutes, then power up the machine and re-check. I would be surprised if anything changed TBH. In your first post you said you'd just bought the tractor. Are you familiar with all the controls, especially the variable speed controls.? Do you have an Operation and Maintenance Manual for it.? You can download an O&M Manual from Cat for less than $50.
Yes I did just buy the tractor. I am familiar with the operations of it. The variable speed works just as it should, when it gets to full throttle. It is doing the same thing as the gentlemen described in first post. Does calibration have to be done by a cat dealer? I called them today and it is going to be around two weeks before they can get to me. How many calibrations is there in the drive system? Is this something I can do, Or does it have to be done through the dealer?
Unless anyone else says different it appears to me as though the calibrations require a laptop loaded with Cat ET software. That’s a dealer job unfortunately.
Ok thank you Nige! I will wait on Cat to check it out.
Back to the subject of a manual. You can download one from Cat for less than $50. It contains a lot of useful operation & maintenance information. Probably the best investment you could ever make, even if you are familiar with the operation of the tractor.
I finally got a chance to take it by the dealer and had them calibrate it. The calibration fixed it. Thank you Nige for the help!