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Troubleshooting Power Bob-Tach not working
- Thread starter willie59
- Start date
crewchief888
Senior Member
ive been reading trying to follow along...
at first it sounds like you might have a bad aux coil, but you mention you changed the RH handle assy, are you sure you have the wires in the proper place in the connector?
the RH paddle switch is a PWM (pulse width modulation) checking voltage at the aux coil you will see variable voltage depending on the paddle position. 2-8 v is about normal, 10v is MAX you should see.
are you probing both wires at the connector, or are you using a seperate ground?
:drinkup
Hi crewchief888 thanks for chiming in,
I checked both coiles, they both have a 2 wire going to them, I forget the color, but I checked the ohms and i think they were around 4ohm, I checked at the plug from the new right hand controller, and when I replaced it I'm 99% sure that I put everything back the way it was, I bought the machine used so I'm not sure if anyone else has switched anything but I wouldn't see why someone would do that, the controller was rusted in place and looked like it was never replace and I don't have a diagram. If someone has color to PIN number I can verify it is correct.
Now, I checked the coils also by putting the front one on the back, and vise versa and also ohms , and also reversing the plugs for them, and when I ise the right hand "trigger" it will open when on front coil, or if I switch coils it will close the bucket, leading me to believe that the coils and valves are working.
When I checked voltage at the plug, with ground hooked to the battery.
I think the first pin was 12v, 2nd ground, than I think it skips a hole and the 4th, is white with red stripe, it had about 4v, with out touching anythin, when I moved the thumb switch to the left the voltage went up to about 6.6 volts, move it to the right and the voltage went down to about 2.2. But, at the coil, I could not get a reading with the trigger or the thumb switch, I'm assuming this is where the pulse width modulation come into play. I'm not sure and this is where I'm stuck..
Also, the left rocker switch did show that 2 of the wires in the plug were 12v, and the right hand rocker showed voltage but I don't recall the colors of wire or pins since I was mostly look for power from the thumb switch to control aux 4in1 bucket
Can I ask where the main board or logic board is kept, maybe it goes to there and I need to check it
Thank you
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crewchief888
Senior Member
try checking for voltage with both probes at the aux connector, you may have a bad ground.
in the RH handle has both 12v and 8v systems 8v is only used for the PWM paddle switch. theres no direct connection between the handle and the aux coils. everything routes through the bobcat controller.
controller is typically on the RH side, inside frame. there are 2 different versions it may have 4 connectors or 2 connectors.
the old 4 connector versions werent as reliable as the later 4 connector and even later 2 connector versions.
old 4 connector controller had a black heat sink sticking out of one end, the later version is slightly smaller in overall dimensions, and does not have the heat sink.
if the controller is bad, they have to be programmed by a bobcat dealer with service software.
:drinkup
I have the 2 wire, at the coils, by coil you mean solenoid, correct? I believe it's a 2003 model, from what I was told.
The controller board, on the right side, is that looking at the machine? I see a black plastic box on the right side looking at it, sitting on the machine it's on the left, under left buttocks!! Opposite side of the aux solenoids.
What is the 2 wire plug for on the aux hydro control, not sure proper name but where the 2 solenoids are, down towards the bottom, I cont get to it because of all the hydrolic lines above it, about 4.
It's dark and I've been using the machine as is but I'll try to check tomorrow for the ground, that would be nice but would baffle me because the trigger works, but any things worth a try. Alsofrom my understanding, that if it were the controller, that I would most likely get 3 beeps upon powering on the machine..
Also I read that I can try reading the voltage by using the hertz setting on my fluke multimeter. Will try that also
Thank you, I really appreciate it!!
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Ok, so I got it apart again, I checked the resistance on the new controller thumb switch, white with red strip, to the white with black strip, against the old controller, resistance is exactly the same on both the old and new, installed, right hand aux controller thumb slide, center switch, that's suppose to open and close the bucket.
I found a schematic, it's wire 4340 that goes to white w red stripped wire, I traced it to the main control box, it is good, also check to see if it was grounded, it is not! I check the ground wires at the connection there for the right controller, unplugged, the white wire with black strip is ground.
Correct me if I'm wrong or there is anything else I can try but i think it's looking like the controller.
05sprcrw
Well-Known Member
This is my first post after buying a used S300 a few months back I joined up and have read a ton on here to help me out along the way.
I had a power bobtach that was leaking and I replaced a few o rings after grinding down a 7/8 extra deep well impact socket I was able to remove the stem with the valve in the loader with ease and it would slide over the stem to protect it, but the valve still leaked. I ended up pulling the valve only to find that it had a crack that ran through all the ports and 3/4's of the way around the entire body. I ended up having purchasing a new valve and installing it. A couple things I wanted to add to what was already said by the gurus are, I found it easier to cut a piece of 5/16 allen wrench about a 1/2" long then slide it into the back of my ratchet wrench to take the valve body bolts loose this really made it much easier then a 1/4 turn at a time with the allen wrench alone. I also found that if I loosened the a/c compressor and pushed it as close to the motor as I good it gave me a lot more room to work.
I had a power bobtach that was leaking and I replaced a few o rings after grinding down a 7/8 extra deep well impact socket I was able to remove the stem with the valve in the loader with ease and it would slide over the stem to protect it, but the valve still leaked. I ended up pulling the valve only to find that it had a crack that ran through all the ports and 3/4's of the way around the entire body. I ended up having purchasing a new valve and installing it. A couple things I wanted to add to what was already said by the gurus are, I found it easier to cut a piece of 5/16 allen wrench about a 1/2" long then slide it into the back of my ratchet wrench to take the valve body bolts loose this really made it much easier then a 1/4 turn at a time with the allen wrench alone. I also found that if I loosened the a/c compressor and pushed it as close to the motor as I good it gave me a lot more room to work.
smokeydave
Member
I am also having issues with power bob tach not working on a S 185 I have been checking and have found 2 issues first no power at center terminal on switch ( all fuses good ) I am assuming that there is a seperate fuse for bob tach . Well I jumped power to the center of the switch and now I get a sound of a hydraulic pump working but no action at the bob tach cyl. where does the power come from to the switch ? Am I correct in assuming that it is fused in the panel infront of the seat? that is a minor issue as I can supply power to the switch easier than I can trace down a broken wire. but I am wondering why no fluid to the bob tach cyl when I can hear the pump whine as if it were having to pump. ( I removed the hydraulic lines from the bob tach cyl and you can move the levers by hand ) so I don't have any thing stuck there. any help I can get would be appreciated.
crewchief888
Senior Member
there is no separate fuse for the PBT
check the PBT cylinder rod, maybe it's bent.
check the PBT cylinder rod, maybe it's bent.
smokeydave
Member
I checked the cyl by disconecting the hyd lines and raising the levers manually ( with them hooked to the cyl so I was pulling the cyl in and out as I raised the levers ) All worked smoothly I wonder if I have a messed up spool valve and when I try to energize the solenoid coils it only moves the valve part way and never opens up the port going to the hose and no fluid can flow
smokeydave
Member
Am I correct in assuming that the power bob tach circuit is 12 volts battery power not a PWM power ?
crewchief888
Senior Member
its 12 v
i would verify that you have voltage to the coils when the switch is rockered in both directions
my best guess is the valve itself is not working.
i would verify that you have voltage to the coils when the switch is rockered in both directions
my best guess is the valve itself is not working.
Mitch619911
New Member
Our bobcat t300 spits out “high flow error ON” and if we check the computer it says something about wire 4460 is getting a voltage when unexpected.
Wire 4460 is a wire that goes from the fuel conn to the J1 or J2 connection but we can’t find the plug called fuel conn, we did find J1/2 on the left panel left of the foot.
We also can’t even find our bobtach valve system? It’s hidden very well!! Anyone know about this error? Our bobtach is currently not working.
Wire 4460 is a wire that goes from the fuel conn to the J1 or J2 connection but we can’t find the plug called fuel conn, we did find J1/2 on the left panel left of the foot.
We also can’t even find our bobtach valve system? It’s hidden very well!! Anyone know about this error? Our bobtach is currently not working.
I have a new S630. My bobtach switch will raise (unhook) but will not lower (connect). I took the bucket off this morning to put the forks on it and now it will not lock into place. I cant get a Bobcat field service guy out here until next Tuesday which simply isnt going to cut it for me. Where is a good place to look? Ive pulled all fuses, I jumped power to the switch harness and still nothing.
DD
DD
crewchief888
Senior Member
you may have a bad coil, or it way be unplugged. PBT & fuel harness is connected on the LH side of the engine, in front of the battery. easiest temporary "fix" is disconnect and remove the cylinder, tie the hoses to the front step, disconnect and cap the lines at the RH upright
I removed the hydraulic lines from the cylinder, placed a drip pan under the cylinder and manually attached the bucket. Then replaced the hoses to the cylinder. It worked to at least get the bucket on. I just have to keep it on there until Bobcat can get a tech out there. Its all under warranty so I dont want to go spending a bunch of time messing with it.you may have a bad coil, or it way be unplugged. PBT & fuel harness is connected on the LH side of the engine, in front of the battery. easiest temporary "fix" is disconnect and remove the cylinder, tie the hoses to the front step, disconnect and cap the lines at the RH upright
Hi All, I have bobcat s650. Power Bob-Tach quit working. I checked the switch with a tester and switch is working. there is no power coming to a switch. I couldn't detect any power just some 0.014 volt. I also checked fuses but couldn't allocate fuse for Bob-Tach in a cabin fuse box(please see attached image) . Any ideas where are the fuses are for Bob-Tach ? Thank you!
Attachments
Chase10
New Member
@willie59
First off, your write-up is amazing. I’m in my infancy of ownership of a used 2012 A300. I like it a lot and the all-wheel-steering is incredible. I am very mechanically inclined and learn on-the-go very well. I have already replaced some ram seals and o-rings, knowing I would have to since I bought a leaky machine. The power Bob-Tach is a nice feature, but has recently stopped functioning. I’m stuck with my attachment on, and I’d really like to figure this out without cracking the hydraulic lines on the cylinder.
I have power at the switch, roughly 13 volts.
The motor doesn’t seem to take load when the switch is actuated, though the system has always required me to throttle-up to get any movement out of the PBT system. (Maybe was a sign of early failure)
The PBT hydraulic doesn’t move in either direction, though I would likely only notice if it were to open.
I have the cab up and some access panels pulled, and I’m trying to narrow down which coils actuate the PBT. What should I be looking for, as far as the actual coils as well as voltage to the coils? What kind of resistance is acceptable? Is there anything that controls the PBT system other than the switch (does it run through the computer or is it direct wire)?
Are there any fuses or relays tied to the PBT circuit AFTER the switch, but BEFORE the coil? (Would explain why I have power to the switch.)
Last thing, and I hope it isn’t a deal-breaker for anyone with knowledge, advice or expertise: some of the wires were chewed through by mice. I’m a low-voltage technician by trade and I have been able to trace all of the wires I have found to be damaged and repaired them.
Any help, advice, questions, comments, concerns, or donations are welcome. You guys are all awesome and thanks for being there for everyone!
First off, your write-up is amazing. I’m in my infancy of ownership of a used 2012 A300. I like it a lot and the all-wheel-steering is incredible. I am very mechanically inclined and learn on-the-go very well. I have already replaced some ram seals and o-rings, knowing I would have to since I bought a leaky machine. The power Bob-Tach is a nice feature, but has recently stopped functioning. I’m stuck with my attachment on, and I’d really like to figure this out without cracking the hydraulic lines on the cylinder.
I have power at the switch, roughly 13 volts.
The motor doesn’t seem to take load when the switch is actuated, though the system has always required me to throttle-up to get any movement out of the PBT system. (Maybe was a sign of early failure)
The PBT hydraulic doesn’t move in either direction, though I would likely only notice if it were to open.
I have the cab up and some access panels pulled, and I’m trying to narrow down which coils actuate the PBT. What should I be looking for, as far as the actual coils as well as voltage to the coils? What kind of resistance is acceptable? Is there anything that controls the PBT system other than the switch (does it run through the computer or is it direct wire)?
Are there any fuses or relays tied to the PBT circuit AFTER the switch, but BEFORE the coil? (Would explain why I have power to the switch.)
Last thing, and I hope it isn’t a deal-breaker for anyone with knowledge, advice or expertise: some of the wires were chewed through by mice. I’m a low-voltage technician by trade and I have been able to trace all of the wires I have found to be damaged and repaired them.
Any help, advice, questions, comments, concerns, or donations are welcome. You guys are all awesome and thanks for being there for everyone!
crewchief888
Senior Member
PBT COILS ARE ON THE pbt VALVE. valve is the square block mounted to the hyd pump on the engine side of the pump