When I start the machine it won’t swing immediately it’ll try to swing but the swing brake isn’t releasing. I can run the stick in and out and it’ll swing or wait a minute or so and Itll swing this was the only error code and it’s active so does that mean one of the pressure switches on the pump is going bad. I’m not thinking it’s a wiring issue because it will straighten right up and I know there’s like four of those sensors on the pump. Any idea which one is which I can’t figure it out by the drawing, thanks in advance.
Just unplug each sensor one at a time and the screen will alert you which is which If your lucky it may just need some brake cleaner on the plug
Ok I’ll checkin it out. Does it need to be running or can I just have it powered up q the key
Key on only Or have it running Doesn’t matter which way you chose Either way the screen will tell you
Well I finally got back to using the machine it’s been a while and I’ve kinda forgot about the pressure sensor issue. It started out same way. Crank it up and it won’t swing. If you let it warm up until it idles down it will swing without issue. I walks it over to the work place start loading the dump truck. Works fine first 2 Truck loads. Then it starts acting up. While swinging the motor sounds like it derates and it’s Fixin to put the swing brake on and stop. Or while binging the arm in while digging about half way in you hear the motor derate as well and it’s in won’t swing mode. When this happens in either function I can boom out slightly and it goes away. Motor revs up and continues to work normal. Sometimes it’s more frequent. I can make it work just by hearing the motor derate and bumping the arm out function I’ll post a pic of the abnormality screen from yesterday. Where do I start. Sorry it’s kinda hard to read.thanks for looking.
Ok now this one ! Went this mornin and started checking it out. There are 3 pump pressure switches on the pump. If you’re looking at the pumps from the rear they’re on the left side one front and one rear. The other one is on the right side. Two on the left side. The one closest to the motor on the left side wasn’t plugged in all the way. I pushed it in and had the screen on abnormal electric view key switch on motor not running. It went haywire. The whole list went to havin a red E on it. I ran the machine and it was still messing up. U could sit there and watch th faults change from red E status back to non fault and not touch anything so I went back down there looking for a chaffed wire etc. one small harness has wires coming out of it for the 2 sensor on the left side of pump. They were both kinda bent hard. I wiggle them and bend them around a litlle. Go back in cab and only one now with and E is the pump pressure switch. But all of the functions are working properly. I ran it for maybe 5 min. So that could change. It’s raining. Simon working today. Maybe it bad spot in that part of harness idk. Sorry for the long post
Went from screen in left to screen in middle when I pushed plug in all the way to the screen on the right whe I wiggled the wires. It’s very difficult when you’re working by yourself to monitor what’s going on on the screen while you’re trying to troubleshoot it down below
Is the wiring oil soaked?
No sir. At least not in the pump cabinet area. I haven’t traced it back to look at it anywhere else
I did a little more digging and looks like I haven’t even located the pump pressure sensor. I was looking at the LS and EPC valves on the pump. Those were the only places I saw electrical connections. I’ll go back and see what I can find maybe they’re on the bottom side I didn’t look there. I do know what I’m lookin for now.
On the older models, Dash 5 and 6, the pressure sensors were at the inlets to the main control valves.
Ok that’s where I’m gonna look. I saw a video and it looked like that may be the location but it wasn’t a good shot at all and it was in a foreign language. I was just waiting for it to quit raining here where I could go look.
Yes they are in the backside of the control valve. I have a 1100 page manual in my files and I found them! Wohoo now maybe there’s a loose connection etc at least I know where to look. The manual is very technical and I’m on lower scale if all that lol. Thanks
I started working on Komatsu machines in 1986 and it took me about five years of going through their service manuals before I finally caught on to their engineer speak. Keep at it and the lingo will rub off on you. It helps a lot of the time to have the manual with you as you work on the machine. Even then more than once I've had to call it a day and compile all the stuff I had done and sleep on it. I'd have a different perspective the next morning.
I went out the casino was excited that I might find the issue at least I knew where to start lol but it was so muddy my shoes were 5 pound a piece w clay. I wasn’t gonna chance tryin to climb up on top of it. Maybe today I can look at it.
The schematic is intense for someone not use to it. I can't look at it now but could look at it at end of day maybe. How many hours on the unit as big hours do point towards wire degradation and rub throughs. It may be simple, it may not. Simon C
Well, I appreciate any help fosho! I went out there this morning and located the front and rear pump sensors on the back side of the control valve and the front pump sensor was not Plugged in all the way I pushed it in, went and checked the screen on the abnormality Electric section and the red E went away on the pump sensor. It seems to walk better than it did and everything is working, but it keeps adding and taking away the red E status on the other functions. I mean, they’ll all come on for a minute and then they’ll all go away by doing nothing just sitting here watching the screen. I don’t know if it’s trying to reset but I played with it for about 20 minutes and it just going back-and-forth, but everything is working except for the auto idle sometimes it does not want to come off high engine and go back to auto idle I checked all the levers nothing seems to be touching. That would keep it from going back to Auto Idle. Here’s a screen where all the red E’s are lit up a screen where one red E is lit up and a screen, where all of them are gone all within one minute oh and it has 7813 hours on it
And this is while running, but no functions being activated just sitting still
So with multiple things happening at once I would be having a look at cab to frame ground, frame to battery ground, possibly a connector that has gotten wet a few too many times. I am headed off to a Dentist shortly, will try to look at schematic and manual to see if something stands out as obvious. If you run the tracks at high speed does anything happen on that front. Will check into later. Simon C
Think I would be testing the harness to those sensors as it must of rained cause you have dirty boots you said. Could be something wrong in harness but would require loading wires with current to test from computer output to sensor plugs. Not sure if you know how to do. Simon C
Oh yes, it’s definitely rained. Machine is basically been sitting for about five months and been doing work to it often and on new pins and bushings, etc. but almost seemed like a rat chewed the wire somewhere. I don’t know. I’m gonna have to clean it a little bit more on some of them harness areas so I could see but the Pump Center, Ford and front and revert front and rear pump is not showing faults anymore and the other ones weren’t showing faults until I plugged in that one harness on the pump it wasn’t plugged in all all the way when I plugged it in it went haywire so somethings going on there no doubt, but I’m gonna have to have help to do all that right now. I don’t have anybody to help me and I did just try out the all three modes on the traveler work fine, low medium and high and it travels so much better now with that without the pump sensor fault before it was like struggling and low to turn now it turns like a dream.
All those sensor are on pilot manifold block that should be somewhere behind the cab or next to the main control valve. You will see all those number 4 pilot hoses connecting to it on one side and another set connected to the other side going to the main control valve spool ends.
Tenfo I pushed on all of them today all had good connections.
I need to clean up some more spots where the harness goes through and inspect it. There’s 12 sides to ever hose wire and panel when you start pressure washing it hehe
Did a fast look at my Dash 8 manual and if I am correct is the serial number group after yours. You have lots of ground connections to test at lots of the solenoids. Check SEN00244-05 Pg 26 to check Lock Lever Switch. Check the PPC Lock Solenoid Check the Diode Array Go to SEN00244-05 PG 92 and more testing SEN00245-04 Pg 52-57 is about swing testing---There is a lot to it. Could be some rusty grounds. Any greenish connections in your battery box. Some simple things to check before the hired hands show up. Simon C
Ok thanks I’ll see what I can find tomorrow or maybe Saturday. The battery box is pretty clean.
Just read one of my replies. I was trying to say the front and rear pump pressure sensors aren’t showing fault anymore since I pushed the connector in all the way. All the fault with red E’s started coming and going when I pushed in one of the connectors to the 3 coils in the side of the pump. That’s when everything went haywire. When I go back out there I’m gonna start by unplugging that connection and make sure it’s not full of water or debris. Idk. I wasn’t like real loose but it wasn’t making all the way. Just strange prior to that only had rear pump pressure sensor withe the red E status but I was have issues it’s very hard to trouble shoot by yourself. Maybe I can find someone to give me a hand next day or so
And I don’t know that pushing that connector in to make a better contact, have anything to do with everything going haywire because it was not showing an open circuit prior to that. And now I remember it could’ve been when I was moving the wires around lookin for anything. Idk. Again it’s very difficult to be on both ends of the machine at once if I had somebody looking at the screen while I was at least juggling wires or connections or something like that would really help but it is what it is and I’ll see what I find out.
Very peculiar that there was suddenly soo many Red E's . Kind of points to a connection problem of some sort. I seem to recall I believe I sent you the manual from 300001-up before but your machine was for serial numbers below. Think you had one of those manuals also, I dont have but clean and dry all the connectors you find there and maybe disconnect the batteries and see what comes up again with a helper is my suggestion. Simon C
Yes, I have two manuals and one of them is definitely like yours cause I went in there and looked at the pages you were talking about. They’re very similar, but yeah that’s what I’m gonna do is. I’m gonna clean and dry everything because actually yesterday pretty much all the ready’s had disappeared and I was just getting one here and there and then I washed the machine because I thought I had an oil leak by the motor. I had someone replaced the valve cover gases cause it was leaking oil and like I said, the machine hadn’t been run in a while really but when I was using it on Tuesday, I noticed oil on the bottom of the cover underneath the motor, but it was watery looking so anyway it looked like it could’ve been coming from the hoses coming from the oil cooler. I washed all that real good and then while I was at it, I washed down all those connections on the valve bank just cleaning everything in general and started it up and I didn’t have an oil leak that was just residual oil and from where the rain had gotten into there, but then it seemed like it was acting up again more than it was when everything was wet so it could very well be just a bunch of wet connections let’s hope so lol I appreciate you taking the time to try and help me do this
Well thought I had it. Started it up went to abnormality screen all clear of redE’s swing it around so I could get to pump. Pulled apart the V17 connector the was suspect sure enough it was wet. I cleaned it out w brake clean and air. Put it back together crunk her up auto idle started workin correctly so started working the functions wasn’t long till the engine slowed down while swinging in new I wa about to lock up. Stopped looked at monitor and here we go all boom functions back to E status. F & R pump sensors still good to go. They have had any more issues. What doesn’t make sense is the only boom functions that give an issue are swing L&R and Arm or stick in And the Atm in doesn’t stop of slow down but the motor will slow down not because it goes to AI it’s while your running higher rpm. Same as the swing by the swing will apply the brake and lock up. When this happens with either function if you hit arm out function it immediately Revs higher and carries on normally. Even though the E status shows up next to all the functions on the screen the others have never given a Problem and even when they have the E status it’s only every once in a while that it gives an issue. Very strange.
Cleaning out all those connectors is a good start. How about all the small grounds I seen on the schematic coming off those solenoids. My guess is that they could go to a common ground. Have you metered the cab to chassis ground and the frame to battery negative ground. If you are not exactly sure how I can PM you the simple enough to do instructions. I was also wondering about that pilot lock solenoid if there could be a problem there. There sure is a lot of junk that could be the problem, without firing off a parts cannon only to find out it still doesn't work. Simon C
Yes I’d like to clean all the connectors on the control valve as well. I haven’t checked any of the grounds yet. Not quite sure how to check as you described. Pm would be great. Thanks
I you have a book go to the cook book section for each code and follow the directions. The cook book will list a code and then it will list possible causes and direct you to do certain tests. Look for the commonality of problems in the cook book and work from that. Right now you are just looking for ghosts.
With all those sensors lighting up at same time it’s gotta be a harness or ground issue I would think. Or possibly pump controller. But not gonna throw parts at it. If I can find some help I'll get back at it.
I pulled all the connectors apart on the pump and any around the valve bank I could get to. Had 1 on the pump and two on top of the valve banks that were wet inside. Sprayed them down with brake clean and blew them out with air. Last week was able to run it 4 days loading dump truck it was all day but only few minutes at a time. Anyway I’ve put 6 hrs on it and it’s been working great. All the E’s have disappeared!! I still want to clean it better than it is and look around. I don’t like a dirty machine especially when you have to wrench on it lol
Poor power in and out of a computer reading sensor will cause lots of problems, with nothing wrong with sensor. Once all clean it could be good until a real problem arrives. And this has mean't no service calls yet. If machine ran for 4 hours straight the shear heat of all the components would help dry thing out also. Simon C