Mitsubishi MM40SR

[Fordzilla]

Hi all,

I have read some of the posts from years back that talk about the Grey Market MM30, MM40, and MM50. Hoping someone can help me. I am getting error code E-22 on the interference display. I have tried everything to make it go away, chased wires, removed sensors and put back on but still it stops the boom extension and retraction completely. Can still track and rotate, also can move bucket back and forth but can't use the boom.
I do know that the red button under the seat temporarily disables the interference box, but that is only good for however long you want to listen to the beep and when you shut off and restart you have to press it again.
I have tried disconnecting the sensors, but still doesn't work. So hoping someone might know of a way to just bypass the monitor permanently (I have never used it yet)? Cut a wire or two? Jump a wire or two?

Any help would be greatly appreciated.

 

[Fordzilla]

So, I did some measuring with a Multi-Meter today. And it looks like the position sensors on the boom have a dynamic resistance range around 1500-2000 ohms (and more depending on how far). Point is, I wonder if I was to install some resistors with say 2000ohms resistance at each of the sensors if it would satisfy the Logic to "Think" everything was good. Although the digital display wouldn't know how high the boom was, it would prevent it from erroring and disabling the boom?
Thoughts anyone?

(Although this is like a ghost town in here and it doesn't seem like anyone is actually listening).

 

[Fordzilla]

Ok, as I talk to myself here in this thread, maybe it will help someone else down the road. Installed 2Kohm resistors into each of the 3 sensor wiring connectors and disconnected sensor. Unfortunately no progress as it just changed the error code from an E-22 to an E-21.
I get E-22 with 1 or more sensors disconnected (without resistors), and then get E-22 with sensors connected. but only E-21 with resistors only. So, no progress, unless I am installing the wrong resistors.

 

[Tags]

I believe people are "listening" I think the problem is not many people have any helpful suggestions since it is a rare machine. As you must have searched around you've probably found that this is a common problem. At least it seems that way to me, almost any post I read about an MM something or other seems to never get a solution, or at least not one somebody wants to share....

 

[Tags]

Try checking this post out....https://www.heavyequipmentforums.com/threads/cat-mm55sr-excavator.14252/page-2#post-709836

 

[Fordzilla]

I believe people are "listening" I think the problem is not many people have any helpful suggestions since it is a rare machine. As you must have searched around you've probably found that this is a common problem. At least it seems that way to me, almost any post I read about an MM something or other seems to never get a solution, or at least not one somebody wants to share....

Oh I know, was just trying to be funny. There seemed to be a lot of discussion in a few other threads on this site a year or so ago. I was hoping to see if some of those knowledgeable people might chime in.
I did post on those threads as well but nothing yet either. :-(

 

[Fordzilla]

Try checking this post out....https://www.heavyequipmentforums.com/threads/cat-mm55sr-excavator.14252/page-2#post-709836

Yup, read everything I could find before I started my own. Even replied on two or three others on here

 

[Tags]

That's a bummer...hopefully someone
chimes in. It would seem to me that someone with some kind of knowledge of the operating system would be able to bypass it…

 

[Fordzilla]

Just wish I knew what e-22 was. I belive e-21 is supposed to be wring issue to potentiometers

 

[Fordzilla]

Ok, here goes. I fixed it! (Or should I say over-road it)

Step 1 (pictures 1 & 2)
- Unscrew top of console, and you will find 2 screws that attach the monitor to the front of the console. Unscrew monitor controller so it is free.
- Disconnect the two wire harness connectors from the monitor controller and feed out of the console so you have the monitor controller removed from the console completely

Step 2 (Picture 3)
- Unscrew the back of the monitor and find the two small red wires that lead around the circuit board to the front. This is the speaker for the horrible beeping noise, disconnect the connector and put the back back on the monitor controller.

 

[Fordzilla]

Step 3 (Picture 4)
- Open the panel under the seat and remove the 4 10mm bolts that hold the fuse panel and buttons on. On the back of the red button will be 2 wires that override the Monitor Controller. Be careful how you pull on the panel as it has bare 12V wires on the back and they can short out on anything metal while you are maneuvering it.

Step 4 (Picture 5 & 6)
- Cut the two wires between the connector and the button, Take the two wires that go to the wiring harness (not the stubs that are remaining on the back of the button) and strip and twist together. I recommend putting a wire clamp and/or electrical tape on this so that it doesn't short out sometime down the road. Put the panel back on with the 4 bolts.

 

[Fordzilla]

Step 5

- Re-Connect the Monitor Controller to the wiring harness in the console. If you push the monitor controller to the forward most position inside the console, you can actually get the top back on properly. If you are unable to fit it in the right place then you will have to feed the wiring harnesses back through the front of the console, reconnect the connections, and attach it back on the front of the console with the original two screws. If you do this however you will have to stare at flashing 8888 every time you use your machine. I would probably suggest you put black tape or something over the display if this is the route you choose.

 

[Fordzilla]

Here are some photos of my machine, it is a Mitsubishi MM40SR.

 

[Tags]

Glad to see you sorted it out! I'm sure someone down the line is going to really appreciate the steps you detailed on how to keep her going.

 

[Fordzilla]

Glad to see you sorted it out! I'm sure someone down the line is going to really appreciate the steps you detailed on how to keep her going.

I was busy trying to figure out how to fix it and override the system when I realized that it already has an override, so why not just take advantage of it

 

[Jemuel]

Hi there, new guy here. I have a MM55SR that the CPU light comes on at console and when I try to move boom in or out. which means the boom does not move. Question is my console is a little different than the 40 could your fix work on my machine. Thanks

 

[Fordzilla]

Hi there, new guy here. I have a MM55SR that the CPU light comes on at console and when I try to move boom in or out. which means the boom does not move. Question is my console is a little different than the 40 could your fix work on my machine. Thanks

I don't know. I would suggest trying the button under the seat first? The reason I took the computer apart was because it was beeping from pushing the button. I also never used anything on it so figured it was best to just get it out of the way. Good luck and let us know how it works out!

 

[Jemuel]

I never had the beep after pushing button. everything works still except the in and out. I have a email out to the folks that have the retro setup. no answer yet to see how expensive that is.

 

[peter squire mm30sr]

Hi all,

I have read some of the posts from years back that talk about the Grey Market MM30, MM40, and MM50. Hoping someone can help me. I am getting error code E-22 on the interference display. I have tried everything to make it go away, chased wires, removed sensors and put back on but still it stops the boom extension and retraction completely. Can still track and rotate, also can move bucket back and forth but can't use the boom.
I do know that the red button under the seat temporarily disables the interference box, but that is only good for however long you want to listen to the beep and when you shut off and restart you have to press it again.
I have tried disconnecting the sensors, but still doesn't work. So hoping someone might know of a way to just bypass the monitor permanently (I have never used it yet)? Cut a wire or two? Jump a wire or two?

Any help would be greatly appreciated.

please can you send me your email or mine is peter_squire@hotmail.com

 

[JDC21]

In dire need of schematic for Mitsubishi 55 SR. Any help will be appreciated !