Bobcat 753 G series LIFT TILT electrical issue PLEASE HELP

[benjaminind]

OH my goodness. I have a 753G machine with Key start on right and display on left. The lift, and tilt functions are not working. THe machine has foot pedals and they are locked! Sometimes when I start the machine it will display a code 18-07 (open circuit on spool lock solenoid), AND 02-17 (Hydraulic filter problem???? still not sure). Sometimes it will start and display no codes - all solid lights after hitting green button but no tilt or lift and pedals are still locked. I have applied 12v to the spool lock solenoids and they work and the pedals move. I have tested the harness when I turn the key and press green button and DO NOT have 12v coming from the harness. Does the signal come from the controller or does it go through a fusebox? I have traced some of the wires but do not want to destroy the loom at the moment if not needed. Does the controller have to get certain signals from other solenoids before it sends signals to the lock spools? What would the BCIS be checking in order to provide a code 18-07 and why might it come and go but the signal not be sent to unlock the spools? The lap bar and parking brake seam to operate correctly based off the display and lights when one or the other is operated. ANy help at this point would be great. All fuses and relays appear to be good. I am stuck and believing it is a controller problem but want to be sure.

 

[Tazza]

I replied to your other post about this.
The controller seems to be working detecting the safety devices are engaged, but not sending the unlock voltage. I don't know if that power wire goes to through a fuse or not, but if it did and it was bad, it would give an open coil code every time as the circuit would be open.
It really could be the computer, but a very expensive device to just try and hope it was the casue.

 

[benjaminind]

I replied to your other post about this.
The controller seems to be working detecting the safety devices are engaged, but not sending the unlock voltage. I don't know if that power wire goes to through a fuse or not, but if it did and it was bad, it would give an open coil code every time as the circuit would be open.
It really could be the computer, but a very expensive device to just try and hope it was the casue.

First off thank you so much for getting back with me. I'm getting a code 18 - 07. I believe that is the open circuit for the spool lock. I do not see any wiring problems but also do not want to cut the entire Loom away. Do you know if the controller would still see a code if it was not sending the signal out? Also do you know where that signal comes from on the computer so that I could test The Wire right after the controller. When I called bobcat and talk to them they seem to think the locks pools could still be the problem but I just don't see how when they never get power sent to them. What they told me is the controller could see it at the open circuit even if resistance was good and the solenoids operated. Does that make sense to you?

 

[Tazza]

First off thank you so much for getting back with me. I'm getting a code 18 - 07. I believe that is the open circuit for the spool lock. I do not see any wiring problems but also do not want to cut the entire Loom away. Do you know if the controller would still see a code if it was not sending the signal out? Also do you know where that signal comes from on the computer so that I could test The Wire right after the controller. When I called bobcat and talk to them they seem to think the locks pools could still be the problem but I just don't see how when they never get power sent to them. What they told me is the controller could see it at the open circuit even if resistance was good and the solenoids operated. Does that make sense to you?

Sorry, i don't know what wires to check.
As you tested them and they open, the solenoids must still be good, or so i'd think.
If they were bad, i'd think you'd get the same code every time. You have checked for voltage at the solenoids and the computer isn't sending any power there...

 

[BC873G]

First off thank you so much for getting back with me. I'm getting a code 18 - 07. I believe that is the open circuit for the spool lock. I do not see any wiring problems but also do not want to cut the entire Loom away. Do you know if the controller would still see a code if it was not sending the signal out? Also do you know where that signal comes from on the computer so that I could test The Wire right after the controller. When I called bobcat and talk to them they seem to think the locks pools could still be the problem but I just don't see how when they never get power sent to them. What they told me is the controller could see it at the open circuit even if resistance was good and the solenoids operated. Does that make sense to you?

Benjamin, if you can add an email address to your profile or post one here I can send you some additional information out of service manual that might help.

 

[Southland]

I have same issue. But it's code 18-06, short to ground unless I unplug both coils then 18-05. Short to battery. I replaced coils even though they pulled in with 12 v. They didn't ohm out as they should. Any ideas?

 

[isoscell]

Hi, maybe your controller is defective. please contact us for troubleshooting instructions, visit our website www.isoscell.com