Bobcatg 753 auxiliary control

[WK Carlson]

The auxiliary solenoids are only getting power to one of them, figured it was the switch in the joystick and installed a new one only to have the same problem. I have 8.5 volts to the one that works and nothing the other. My next step is checking all connections but am thinking its probably the solid state controller box. Any thoughts on what else could be the issue before I dish out another large chunk of cash?

 

[WK Carlson]

Well I went to the Bobcat dealer and found them to be at least 2 months out so that wont work.
I decided to make a slight rewire on the auxiliary hydraulics. Ended up cutting the power wire at the working solenoid and put a 3-way switch in the cab so now the toggle that works is poweriing both solenoids. Not real handy but I can use the grapple, I just have to flip the switch between solenoids either in or out. This will work until I can schedule an appointment for the proper repair.
Thanks,

 

[reaperman]

Clever idea

 

[dynapl]

Well I went to the Bobcat dealer and found them to be at least 2 months out so that wont work.
I decided to make a slight rewire on the auxiliary hydraulics. Ended up cutting the power wire at the working solenoid and put a 3-way switch in the cab so now the toggle that works is poweriing both solenoids. Not real handy but I can use the grapple, I just have to flip the switch between solenoids either in or out. This will work until I can schedule an appointment for the proper repair.
Thanks,

Hi, I'm currently trying to troubleshoot my axiliary hydraulics which are not working. Would you be able to snap a photo where you were measuring voltage and where did you wire into the solenoids?

 

[WK Carlson]

I measured the voltage from the connector at each solenoid from each pin to ground. only one had voltage of around 8.5 V. This is the wire that I spliced into for my 3-way switch work around. Ran the switched wire to the dark screw on the switch and the other two back to connect one each to the solenoids. Kinka clumsy but it did allow me to complete the projects I had before winter. I used a regular house wiring 3-way switch then taped it up so no shorting out. Then taped it to the cross arm for a little easier access for switching between grapple open and closing. Unfortunately, I did not take any pictures of the work. Hoping to get it into a bobcat dealer this winter to replace the ACS control panel at least thats what I think its called.
That should get it back to operating as normal.

 

[rblinton]

Huh... I have exactly the same issue and have bought the switch for the same temporary solution (but not yet installed). I also replaced the hand control ($500+ yikes!) which did nothing. (Anyone want to buy a used R-hand control for a 753 G Series?)

The issue started years ago when my Bobcat had some major electric failure resulting in a service call where the mechanic replaced my main controller with a used one that is not an exact but close enough fit for my serial number. That got my Bobcat running but not fixed, and is how I've been operating it since. Only one "side" of the aux hydraulics now works. The mechanic suggested replacing the complete wiring harness but that's not how I usually like to solve issues and I have not done that. I've got the wiring schematic and checked continuity for all connections coming out of the R-hand control to the main controller then to the solenoids and they all look good. I'd like to find a way to test the main controller itself.

Good luck with your repair. I'll be following your posts...

 

[WK Carlson]

Huh... I have exactly the same issue and have bought the switch for the same temporary solution (but not yet installed). I also replaced the hand control ($500+ yikes!) which did nothing. (Anyone want to buy a used R-hand control for a 753 G Series?)

The issue started years ago when my Bobcat had some major electric failure resulting in a service call where the mechanic replaced my main controller with a used one that is not an exact but close enough fit for my serial number. That got my Bobcat running but not fixed, and is how I've been operating it since. Only one "side" of the aux hydraulics now works. The mechanic suggested replacing the complete wiring harness but that's not how I usually like to solve issues and I have not done that. I've got the wiring schematic and checked continuity for all connections coming out of the R-hand control to the main controller then to the solenoids and they all look good. I'd like to find a way to test the main controller itself.

Good luck with your repair. I'll be following your posts...

Well I replaced the right hand control also thinking the toggle switch was bad. Had the same result so I too have a good RH control. I checked all my wires and connections and do believe the problem is with the main control box.
From what I read it has to be changed and adjusted by the dealership or service center

 

[WK Carlson]

Well I replaced the right hand control also thinking the toggle switch was bad. Had the same result so I too have a good RH control. I checked all my wires and connections and do believe the problem is with the main control box.
From what I read it has to be changed and adjusted by the dealership or service center

Not really happy about that because it's going to be expensive. I think the control box or ACS I think it's called runs around $1,800 or so. So I'm a little nervous on what the total cost will be.

 

[dynapl]

I measured the voltage from the connector at each solenoid from each pin to ground. only one had voltage of around 8.5 V. This is the wire that I spliced into for my 3-way switch work around. Ran the switched wire to the dark screw on the switch and the other two back to connect one each to the solenoids. Kinka clumsy but it did allow me to complete the projects I had before winter. I used a regular house wiring 3-way switch then taped it up so no shorting out. Then taped it to the cross arm for a little easier access for switching between grapple open and closing. Unfortunately, I did not take any pictures of the work. Hoping to get it into a bobcat dealer this winter to replace the ACS control panel at least thats what I think its called.
That should get it back to operating as normal.

Thank you for sharing the information. I got hit by COVID that I thought was just the flu and got my whole fam sick. This combined with the swift onset of winter in Chicago, created a situation where I was not particularly enthusiastic about delving into troubleshooting the issue. I'm looking for some break in the weather i.e. above 40F to get back to it. I'll post my findings here.

 

[polishpete]

maybe the valve is stuck

 

[oiu789]

Did you find out any more?

 

[mibh1]

maybe the valve is stuck

How would one test for that?

 

[rblinton]

How would one test for that?

Swap the connections to the two solenoids. If the one that was not working now works, then it's not the solenoid or valve that has failed. In my case I was connecting a grapple which would only close. After swapping the connections it would only open, therefore my issue is farther up the line - hence why I need to check my controller.

 

[richmond802]

Swap the connections to the two solenoids. If the one that was not working now works, then it's not the solenoid or valve that has failed. In my case I was connecting a grapple which would only close. After swapping the connections it would only open, therefore my issue is farther up the line - hence why I need to check my controller.

I'm having the same exact issue with my grapple. I need to switching the connections to the solenoids apparently to see if that's my problem.

 

[Rumrunner439]

Well I went to the Bobcat dealer and found them to be at least 2 months out so that wont work.
I decided to make a slight rewire on the auxiliary hydraulics. Ended up cutting the power wire at the working solenoid and put a 3-way switch in the cab so now the toggle that works is poweriing both solenoids. Not real handy but I can use the grapple, I just have to flip the switch between solenoids either in or out. This will work until I can schedule an appointment for the proper repair.
Thanks,

So the Auxiliary solinoids are the 10v ones on top? I wish you had taken a few pictures. I have zero working for my Auxiliary and can't use my grapple right now. My controller aka computer is bad. I bypassed it for now, powered the boom, bucket solinoid and a start switch and energize the alternator so it charges. But I need to do like you did until I get my new main controller. Mine is also the 753g model.

 

[WK Carlson]

If I get my unit back into the shop I'll take some pictures of what I did. As for testing I did exactly what a few of the posts had mentioned. Swaped the solenoid connection wires and thats how I got to where I'm at. With Christmas coming the shop has turned into a display and wreath making area for my wife, won't be moving anything till that's done with.