CAT0299DLGTC00836 I have been running a CAT T9 trencher for a week with no problems. Today when I installed it back on the machine the trencher wouldn't turn. Sometimes it would turn it a quarter turn and just stop. I read there is an implement solenoid to check but I don't know where it is. Anyone know what might be wrong or where the solenoid is?
You didn’t by chance hit the switch turning off the auxiliary hydraulics did you? I can’t tell you how many times someone’s got in one of ours and couldn’t get them to work because someone had hit the switch by mistake.
Do you have deluxe monitor or basic gauges? If solenoid is bad electrically, there'll be a code in deluxe display.
Never mind...you have basic panel.
HMC. I think from memory this machine might have had that panel retrofitted. We went through that process somewhere in the OP's first ever thread - or I could be thinking of a different panel. See post #194 & following ........ HeavyEquipmentForums
There must be a short somewhere. If I hit the continuous flow button (which I have never used) it would unlock it. I has to do that a few times during the week and was able to complete the job.
Disconnect and recouple the hydraulic hoses, sounds to me like a quick coupler has an issue. Observe the hoses when you try to engage it, see if they're jumping and staying pressurized.
I am having the problem again. This time it is worse. The aux. hydraulics are not doing anything. The lines are not shaking. My best guess is there is no power to the "rolling" switch. I have an upgraded panel and no codes are thrown. I checked fuses and they look good. BTW I just did a bunch of work up front and had the hoses disconnected up front. Not sure that matters.
The aux "roller" switch has 4 wires that go into it. I assume one is constant voltage, one is ground and the other two return voltage to the ECM. I would like to test for constant voltage going into the switch but don't which wires do what.
I may be wrong but I thought I sent you an electrical schematic a long time ago when you had your first issues just after acquiring the machine Correct me if I’m wrong.
I have one and I am narrowed down to the joystick but cannot quite understand it. I'll have to go back to the shop and look at the wire colors to see if I can match them up to the schematic.
You will find that every wire has not only a colour but also a number. The number appears on the schematic and is also marked every 6” or so along the length of each wire. Match the number/colour combinations from the schematic up with what you find physically on the machine.
That's what I'm trying to do. I'm having a major dumbass moment though.
Here is the Right Hand top of the joystick
Here is the shematic
OK, I can see the issue. You need to look at the machine wiring harness connectors (1 x 6-pin, 1 x 12-pin) that are located in the armrest below the joystick for the colours and wire numbers. They are the wires that are shown on the schematic below. The short "fly leads" located on bottom side of the joystick are not shown on the schematic.
Great. Thanks. I'm not a total dumbass. So frustrating!
I'm not getting power to pin 1 "Roller Power". Not sure where to go from here.
Follow Wire #127 Orange back on the schematic and see where it comes from.? I assume that you had the key in the "ON" position when measuring the voltage.? Note: the Blue colour of Wire #127 as drawn on the schematic indicates that it should have power ONLY when the key switch is in the "ON" position. There is a table on Page 2, Grid A-4/A-5 of the electrical schematic to decode what the colours on the schematic indicate as regards the function performed by the wire. NOTE - these are NOT the same as the 2-letter acronym for wire colour.
I had it running.
Well that rules that out then........... If you follow Wire #127 back on the schematic it comes from a dedicated 10A fuse in the fuse panel marked "RH J/Stick Base". Maybe the output side of that fuse should be your next port of call.?
I'm curious what this switch does? The one with the rabbit and aux on it. I don't have the operator manual in front of me but the repair manual doesn't show it. I have pushed it both ways with no results.
10-4
Wire 127 in CH-C3 has power at the Deutsch connector under the arm rest. I checked it yesterday. Wire P984 in CH-C2 also has power.
At CH-C2 look for power on P769 YL. It is power supplied from the ECM so you will have to use wire P770 WH (Pin 2) as the ground, NOT machine frame ground. Should be 8V. What voltage did you measure in Wire 984.?
no power on p769. 13.8 volts (grounded to frame) on 984
Was that measurement made with the Aux Hydraulics "activated". I am not 100% certain but I suspect that power will only show up on P769 if the Aux Hydraulics have been requested.
I'm trying to figure out how to activate it. Is it the switch I post a picture of?
That is the 2-speed/AUX 7 control. The purpose of AUX 7 is to provide electrical power to Pin A on the loader arm connector. Push the top of the switch inwards then use the trigger on the LH joystick to control 2-speed. Push the bottom of the switch inwards then use the trigger on the LH joystick to supply electrical power to Pin A on the loader arm connector.
Got it. But is there a switch that controls the aux hydraulics I need? People have mentioned it but I don't ever remember hitting a switch?
Not that I can see. This is the best explanation I could find for engaging the AUX hydraulics. When thumb wheel (29) is moved, pilot oil is directed to the auxiliary circuit spool located in the control valve. Thumb wheel (29) is a proportional switch. Move the thumb wheel slightly for a small amount of flow to the auxiliary couplings. Move the thumb wheel further in order to obtain a higher flow to the auxiliary couplings. When a high flow work tool is detected by the ECM at the work tool electrical connector, and the thumbwheel is at 100% the switch will trigger the high flow mode giving maximum flow. Refer to "High Flow Mode" in this manual. Move the thumb wheel forward in order to increase the flow of oil to the male "Aux 2" coupling. When you move the thumb wheel (29) forward, the ECM activates a solenoid allowing pilot oil from gear pump (charge oil) to activate the AUX spool. Supply oil from the piston pump (work tool) flows through the spool to the male "Aux 2" coupling. Oil from the piston pump flows through the work tool circuit and retiurns through the female "Aux 1" coupling to the spool for the auxiliary circuit. The oil then flows from the control valve (work tool) back to the hydraulic oil tank. Move the thumb wheel backward in order to increase the flow of oil to the female "Aux 1" coupling. When you move the thumb wheel (29) backward, the ECM activates a solenoid allowing pilot oil from gear pump (charge oil) to activate the AUX spool. Supply oil from the piston pump (work tool) flows through the spool to the female "Aux 1" coupling. Oil from the piston pump flows through the work tool circuit. and returns through the male "Aux 2" coupling to the spool for the auxiliary circuit. The oil then flows from the control valve (work tool) back to the hydraulic oil tank.
Yep. That puts me back to the beginning. The thumb wheel is not getting voltage.
Try going back along P769/P770 from C-CH2 towards the ECM and look for voltage on P769 using P770 as ground. CONN 13 is one major harness connector betwee the joystick and the ECM. The schematic shows the locations of the major harness connectors. P769/P770 feed a number of functions (track motor speed sensors & ILEV cystem) not just the roller switch. I think you might have a wire break in a harness somewhere, possibly between Conn 13 and the ECM. I can see a 5-way internal splice of both wires P769 and P770 on the schematic. See Grid D-14, illustrated below.
No voltage to those wires on conn 13. Next is ECM I guess. The cab is in the air with the arm rests down and key on.
The ECM is right next to the Conn13 and it looks like it goes into J2 but I don't see P769/P770 on the schematic of J2.
P769 - Pin 56 P770 - Pin 30 Both on connector J1. I'll bet you find 8v between those two pins at the ECM with the key on - because you have no Active Diagnostic Codes for your drive motor speed sensors that are powered using 8v by the same P769/P770 wires.
How did you find that!!! You are a genius. You must have this thing printed out on a 4X8 piece of plywood.
No. much easier than that. The pdf document is searchable. Put P769 in the Adobe pdf Search Box and then click either the Search Forward or the Search Back icon. It will take you one by one to every location on the schematic that "P769" occurs. If you want to find a wire in a specific harness (e.g. Harness "C") you could for example put "P769-C141" and it would only show you that wire.
If you find power between P769 & P770 at the ECM J1, your next step should be to find whether it is wire P769 or P770 that has the problem. Disconnect ECM J1 and CONN 13 then measure the resistance of wire P769 within Harness C between the two connectors. (J1 Pin 56 and CONN 13 Pin 42) Repeat the process with wire P770. (J1 Pin 30 and CONN 13 Pin 43) It is my opinion that one of them has to be open circuit (infinite resistance). When you find which one it is you could temporarily run a wire outside the harness from J1 to CONN 13 to replace the defective wire so that you can at least power up the roller and test it.
I have no power at the ECM between P769 and P770.
Was that with ECM Connector J1 disconnected or were you measuring in the back side of the connector..? Measuring into the back side of one of those 80-pin connectors can be difficult without the correct adapters for a DMM because the pins are buried so deep inside the connector. The reason I ask is that machine power also comes into the ECM via three different piins on connector J1. Therefore if J1 was disconnected there would be no power on anything.
I measured it from the back and with it disconnected. I have many different ends on my multimeter. I used the long skinny ones. They are like needles. I got them last year when a CAT tech was out and he was using them.
Try re-connecting J1, and J2 as well if you also disconnected that one, then test again on the same two pins (30 & 56 IIRC) please.
OK. I think I did that but not sure. Will try in the morning.
3 power and two ground feeds (69, 81, 82, 84, & 85) on Connector J1. See below.
Thanks. Yeah. I was going to try that when I was checking but I didn't have the schematic to tell me which was hot.
I have power at J1 84 and 85. I have ground at 30, 81 and 82. I do not have power at 56 and 69.
You should have power as follows: - 12v between either of Pins 84 or 85 and either of Pins 81 or 82 (or machine frame ground) permanently so long as the machine battery is hooked up. 12v between Pin 69 and machine frame ground with the key ON. 8v between Pin 56 and Pin 30 with the key ON.
Correct. But I don't have power at 56 and 69. I've measured multiple times. Maybe the cab in the air has something to do with it?
It could have. TBH I’m not sure, but it doesn't seem logical. Maybe someone else can comment. The thing is that J1 Pin 69 is incoming switched power from the key. Without that Pin energized all sorts of things that are controlled by the ECM shouldn’t work. The only thing I can suggest is to go all the way back to the key switch and look for power between Wire #308 YL and machine frame ground at that point with the key in the ON position. If you have power at that point then follow 308 YL towards the ECM via CONN 12. I can see a couple of wire splices in 308, one between the key switch and CONN 12, the other between CONN 12 and the ECM.
It might if CONN 12 was disturbed when you raised the cab........ See the location on the schematic, back LH corner of the cab.
X 2 If you have no switched power into the ECM at #69 all sorts of crazy things will happen.
I didn't check those pins at the ECM again. I put the joystick back together cleared all the codes and the stupid SOB works. I put an hour on it and it works. Who knows? Probably an electrical gremlin that will keep haunting me.
Well now's the time to make sure the ECM is getting switched power on #69. Least you know what to check if it faults again. Just out of curiosity were you using these to back probe the wires on the ECM when checking for power?... Edit: the purpose for rechecking is to verify you were checking properly the first time. If it's running properly and it still has no power, your not checking it correctly. Just thoughts.
I do not have the cat probes but one that are similar. I understand what your saying but I checked 4 power pins and got power on two but no power on the other. Hard to believe I was checking them wrong but anything is possible.
Was there a long list of Codes.? Can you remember any of them or did you make a note of them.?
I didn't. Nothing that caught my eye as strange. Wheel speed sensor, 8 volt something, high coolant temp, high fuel temp?, joystick stuff, some voltage thing on cylinder 1 and 4. Most stuff I've seen over the last year except the joystick one (which is probably because it was disconnected.
Both as a result of the lack of the same 8v power supply from the ECM that feeds the joystick roller control. Probably the others are also.
It could be a bad pin in the ECM. In 2020 CAT was out and fixed one inside the ECM.
I wasn't aware that any Cat dealer was qualified (or allowed) to open up an ECM. I'll say this though. Keep an close eye on your Diagnostic Codes, especially anything to do with the 8v sensor supply, drive motor speed sensors, or ILEV (if equipped). That will be the same issue rearing its ugly head again. I noted that your machine does not have a cab according to the system, only an Open ROPS setup. If that is correct then you ought to pay specific attention to preventing moisture ingress to all the major harness connectors including those on the ECM. The Deutsch connectors that Cat use are not 100% guaranteed to be resistant to moisture.
I put dielectric grease into each one I open.
That certainly won’t hurt.
If you want to go belt & braces on electrical connectors, find some vulcanizing/amalgamating tape and once you have cleaned the connector, applied dieletric grease, and reconnected it, then wrap the outside of the connector in amalgamating tape. You can be pretty sure after that nothing wet will get in from outside. On a machine with an Open ROPS such as yours it might make sense to do this. https://www.amazon.com/GTSE-Amalgamating-Rubber-Waterproof-Repair/dp/B0859L6NYP/ref=sr_1_5?keywords=self+amalgamating+tape&qid=1649084734&sr=8-5&th=1 Be careful applying too much dielectric grease to smaller connectors, you can potentially "hydraulic" the connector and split it open when you reassemble it.
Nice. I've wanted something like that--didn't know it existed. I put about 3 hours on the machine today and got the usual wheel speed sensor warning and the 8v warning. I need to trace that down. The machine is usable but once today it took a few seconds for the aux hydraulics to kick in. Also, I bet the four wheel speed sensors I kept when I replaced are still good.