My skid steer I purchased has no hydraulics. I have pilot pressure around 1000psi. Cooling fan will not spin as well. All couplings and shafts are good. I need a picture of the pump lines and connections to verify they are correct. It is a 2014 227D. Fuses and relays in the cab and underneath are good any help would be appreciated.
To find the appropriate information a Serial Number is required. Question: Have you cut open the hydraulic filter to check for the presence of debris in it.? that might be a good first step.
I cut the filter no debris. Serial is FMT00336.
I do not have a manual for this skid but I need to get one to verify pressures. I think 1000psi charge is way too high, but I’m unsure how to adjust it given there are two adjustment screws on the compensator. My other bobcat skid steer only has one.
Also can you elaborate a bit on "no hydraulics". Are you referring to implement operation, the hydrostatic drive system, or both.?
Both, I was testing the wrong port for charge pressure that would be implement pressure at 1000psi.
Here's the pressure taps and testing.
And the lines illustration for the pumps. Charge pump failure maybe.?
I’m believing so but I don’t see any metal in the filter at all. Fan is not spinning as well
Took the charge pump off band checked vanes. Previous owner must have changed the fluid or put a new filter in to fool me…♂️
Vanes are worn housing is worn out.
Thank you for all the help Nige, I will post back when I get the new one installed if everything starts working.
Bugger. Double bugger even.
I got this skid steer for a good deal so I won’t complain. 2014 277D state maintained vehicle with 3100hrs for $23k.
No go fan spins now have about 400psi of charge pressure but no implement controls or movement. How do you test the interlock solenoids outside of the cab?
Not sure what you are referring to. Post a photo of what you are looking at maybe.?
One is implement shutoff the other is 2speed.
If you'd said that in the first place........ Implement pilot solenoid 7.70 ± 0.39 ohms 2-speed solenoid 4.72 ± 0.24 ohms.
Thank you.
Too bad they aren’t in that electrical schematic you sent me
I’m going to have to print it off and go through and right the resistances down on the schematic.
I’ve got no pilot pressure on the implement manifold. Don’t think that will effect the hydrostatic function but it still has no hydraulic functions.
Am I able to test charge pressure at the sos port on the fan?
No. Refer back to Post #7 on Page 1 for pressure tap locations. Charge pressure is for the hystat system.
I figured. I have charge pressure at the pump but nothing on the Hystat system. Looking at the hydraulic schematic I found a stuck solenoid for X7 but no charge pressure at the tap on hystat. My fan seems extremely slow as well do you think a bad fan motor could cause this issue?
If you are not finding sufficient pressure compared to spec at 1 or more test points I would hazard a guess that the fan motor is a symptom of the low pressure rather than the cause of it.
If I pressurize the filter out line with air I get bubbling in the cooler and tank. I believe a valve or solenoid must be stuck somewhere allowing the air to go to the case. I pulled the relief valve and verified it is clean along with the x7 solenoid that was stuck but now moving. Can’t build pressure if it’s going somewhere right?lol
The fan comes directly off the new charge pump.
Collapsed line maybe?
Changed the fluid today and strainer in the tank. Oil looks like it mixed with something could be water intrusion. Somewhat milky but deeper brown lots of air bubbles.
Plugged off ports on hystat. Still no charge pressure to the gauge anyone have some insight?
To bring this thread out of the archives I have fixed the loss of charge pressure. I hade a final drive rotating assembly that rapidly disassembled itself. I put 2 new final drives in from Texas final drives and it moves now speed sensors have power and work but I still get codes for them even after running for a bit. The tracks start at different times and one is slower than the other maybe it just needs a calibration now. The implement shutoff solenoid will not actuate. I can actuate it manually with a test box and I have checked the wiring back to the ECM. I do have a new warning for auxiliary lever #1 voltage above normal but I don’t think it should effect the operation of the right joystick. The code present is 2204-3.
See attached. You will need a multimeter that measures duty cycle.
Thank you. I will follow the steps but I’m thinking ECM given the implement shutoff solenoid won’t actuate as well. I would think it would still work even with the roller switch being faulty.
After following the procedure in step 4 I’m getting infinite resistance or no continuity at all to all terminations in J1 and J2 is this normal?
Yes. You are looking for a minimum resistance of 5000 ohms (or preferably open circuit) to confirm that the sensor signal wire P996-GN is not shorted to any of the other wires in the harness between the sensor and the large ECM plugs J1 & J2. This is why the procedure instructs you to measure the resistance between P996-GN and each of the other wires in J1/J2 in turn . So from a quick look at the schematic you probably have well over 100 wires to test individually. OL measured between P996-GN and all the other wires in the harness at connectors J1/J2 indicates the sensor has failed and should be replaced.
I thought it was just to the wires in the schematic for everything from the RH joystick so total of about 9 wires, if it is all of them then I will check again.Crazy to think it was fine until I got the drives put in it failed. The reason I am thinking ECM is new sensors in the final drives still don’t work and I have codes for 1 and 2 on both sides as well and they all connect on J1. If there is another short somewhere in the harness I wonder how they would associate to those wires given all the wiring is off the back of the cab straight to the ECM and not through the rest of the machine. Unless maybe it’s where they all junction together to tie into J1. Looks like it’s going to be a long day for me
I can’t thank you enough for all the help Nige they should just call this forum ask Nige because it seems like you’re the only man with all the right answers. Thank you.
A few posts back you said the only Code you had was 2204-3........... So you also have 2685, 2686, 2687, & 2688 but with what suffix. -02, -08, etc..? I assume they are all the same.
Basically if a wire or wires has rubbed on P996 somewhere inside the harness and created a short it could be any one of them. That's why you have to test each one in turn to P996.
Current active codes are 2687-8, 2688-8, 2685-8, 2686-8, and 2204-3.
New sensors on both final drives.
Just got done checking all wires in the connectors and no continuity on any of them to P996
Attached the troubleshooting for all the speed sensors -8. Read through them carefully. You will find a lot of the steps are common between (maybe) all four sensors but certainly the two sensors on each side. Remember that there are two speed sensors in a common body with a common power supply and ground.
Sensor wires are good so either both sensors and auxiliary are bad or the ECM is bad.
I have seen ECMs go bad but it is very unusual in later-model D-Series machines (not so unusual in earlier models because they were installed under the floor). You said you fitted two new speed sensors - genuine OEM or "will-fit".? I wonder if your snazzy new drives are not playing well with the speed sensors.?
New OEM
In that case the question regarding the new drive motors still applies.
I’m going to give them a call and see what they have to say.
I’ve verified the drives are not the issue with a test bench and a scope meter. Verified all wiring no shorts anywhere on the 8V circuits. I have checked the schematic and the association of both the roller and speed sensors is the ECM. I believe the problem is the ECM. I have checked all wiring to the 8V system down to all sensors and returns. There is a pressure sensor on the lift lines that isn’t showing continuity across any of the terminations inside but I don’t believe the ECM would ignore anything else because of it. I can pull the ecm and open it up to check but I am pretty sure it is the culprit. Thanks for the help Nige.
Should I be getting continuity to ground on the machine to the 8V return side? Has good continuity to ground even though it says it’s ground it only ties back to the ecm I’m wondering if the 8v return side is grounded at the plugs I get 8v between yellow and white and yellow to ground on the frame.
I'm not sure TBH. I always considered it a return wire to the ECM for the 8v supply, which is produced internally within the ECM. At the connector under the joystick you should measure 8 ± 0.5 volts between Pins 1 & 2 (P769-YL & P770 -WH). Then if you switch your multimeter to Duty Cycle and measure between Pins 2 & 3 (P770-WH & P996-GN) you should get 50% duty cycle with the roller in the centre position, close to 0% with it rolled all the way one way, and close to 100% with it rolled the other way. All other measurements mean nothing.
I am getting 141.6ohms of resistance between P769 and P770 when applying probes to the backside of the ecm connector on pin 56 and all sensors on sensor returns.
I’m getting 99.8% in center when connected. I got a new handle and took both of them to the test bench and they read correctly at 50 in the middle 98 rolled up and 23 down. They both do the same thing when connected. I still haven’t pulled the ecm. Left side speed sensor reads 698.4 ohms of resistance between pins 32 and the connector P770 so I believe that is one problem but with it disconnected I still have an issue.
Almost as if there is a failed triac in the ecm.
Bad ground in the harness was the issue to the ecm all sensor issues fixed. No alarms but the right joystick has no function. Hydraulics not locked out door switch, lap bar and seat works.
Lockout solenoid works actuates and charges the manifold
Want to bet against having another harness fault somewhere.?
Most likely, I’m going through the schematic now. On the screen I can see in service menu the full function of the right hand joystick axis both x and y in all directions. No lockout lights or any alarms so my bets is it’s another ground or wire broken. Given I can see the axis functions on the screen I can rule out the joystick it is most likely the solenoid circuits or a lockout function that isn’t lighting up a light.
I bought some very small probes that work excellent in the solenoids and connectors without disassembling anything it’s made it a lot easier. CAT ET is on the way.
I’m getting 5Vdc on all solenoids at 100% actuation. Are the solenoids proportional? Maybe just needing calibration? Even at 5V you would think it would have some movement.
I may have mentioned this before but a 2-3A test light can be very useful in proving continuity in a wire. Sometimes a multimeter can indicate continuity but putting a decent current through the wire can produce a somewhat different result.
Given it’s a 12V pwm shouldn’t I have 12V instead of 5? That voltage reference should be sent from the ecm but for some reason it’s 5Vdc
Which solenoids specifically are you referring to.? If you can also give the wire numbers that feed them so much the better.
Implement manifold solenoids. The auxiliary works with the roller switch but the others do not function. With a DMM I’m seeing 5.06Vdc.
Those solenoids are proportional (not PWM, that refers to signals not operation, the schematic is wrongly labelled which is not unusual it seems for Cat's electrical dept.) but will also work when full-fat 12v is applied to them. That's basically the test of whether or not they work. Have you tried that.? Also check the wire H802 - common return for all 6 solenoids. I would suggest to load test it with a test light rather than simply check continuity with a DMM.
I’ve tested them out of the manifold with 12V and they work. Won’t be the last time cat schematics send me down a wrong path. Will be testing more later today
Found several stuck spools in the manifold. I have new ones installed but pressure settings look off for the implement system. Does anyone have a setup procedure for a load sensing standard flow pump? I have an implement T&A file but it still doesn’t say anything on how to adjust the load sense and main relief valve.
I have everything installed and working but with the new speed sensors I am getting E568-2, E569-2, E570-2 and E571-2 when operating the machine in the opposite direction the sensors are stating it’s moving.Checked all sensors for water and contaminants still and they are clean. I don’t know why it will throw codes in the opposite direction it is moving before it activates the parking brake.
Attached the troubleshooting procedure for unexpected motor speed. Try looking at the joystick position sensor duty cycle for all Front/Rear and left/right signals. Do they change smoothly from 50% in the centre up and down to 10/90% depending on which way you move the stick.
Joystick is smooth through to 100% and -100%. RPMs of the left and right motors are showing negatives while running they will read zero at stop and run whatever rpm for awhile then drop to a negative number and activate the alarm. I’m pulling the sensors again but it’s unknown why. I did have metal shavings on the right side speed sensor the last time I pulled it and cleaned it. Should there be metal in there or are these new final drives bad?
I’m still in doubt as regards one or both of your replacement non-OEM final drives TBH. And no there should not be metal shavings on the sensor, unless the drive is in the process of suffering a mechanical hernia.
That’s what I’m thinking I’ll pull them and if it has anything on there I’ll get ahold of the final drive company again.
Is there supposed to be shims on the sensor. I found mine has worn a spot on the end it has to be coming in contact with the ring inside.
There are no shims, at least not by design. If the tip of the sensor is coming into contact with the tone ring then either something would appear to be wrong inside or possibly the case is incorrectly machined allowing the sensor to sit too deep. Is it just one sensor or both that are worn at the end.?