Just bought a 2006 CAT 248B with high flow XPS option. My problem is this... I have 3 sets of hydraulic connectors, one set really small I assume for very small items, then 2 larger with one a little bigger than the other. I have a grapple bucket I hooked up to the fittings it fit, which were the larger ones (but not the largest) and I get no action from the controller. There are 2 buttons on the right controller and a thumb jog wheel switch. From my understanding the jog wheel is what operates that aux circuit however it does NOTHING, I can push the buttons next to it up and down and the machine bogs I can tell its making hydraulic pressure but its not operating the circuit i need. I am assuming its running the small set of fittings maybe? I am new to cat and have tried all different button configs to get that circuit to work. I have checked all the fuses as well. I think maybe I am just doing something wrong? Or maybe the actual jog wheel switch is bad.... Can anyone point me in the right direction? The fittings are on very top elec connection, under that male and female very small fittings, then under that the largest set ( I assume is high flow) then the almost as big as the high flow set on the bottom, which is the size I need to connect to with any of my grapple buckets.
See if the attached is any assistance. Also if you don't have an Operation & Maintenance Manual it would be good to get hold of one. A lot of info that you might need including this extract here. Can be downloaded from Cat in pdf form for around $50, or look for Cat Publication SEBU7731 online.
After reading that pdf file closely I have a better understanding of it I am pretty sure my issue is I need to press hydraulic switch under park brake switch to the left for standard hydraulic and it will work, it must be set on high flow (right direction) me where as there are no elec connections to the high flow plug it won’t give flow. I can’t wait to try tomorrow.... I could have sworn I tried moving every switch but maybe I missed that order. I’ll report back thanks!
To engage High Flow on an attachment that does not have an electrical connector will require a jumper plug installed in the electrical connector at the end of the lift arms. This creates the required input into the machine ECM to activate the HF. Need a Serial Number to identify the correct Part Number of jumper.
I’m not looking to engage high flow. I’m looking to use standard flow connections for my grapple buckets. I am aware of the electrical jumper or plug for high flow tools. I am pretty sure my issue is in the thumb roller proportional switch. I’m headed to shop now to try switching the connections from the b aux circuit which works properly with the other buttons next to proportional thumb roller to the a aux circuit which should allow me to operate that circuit with on off momentary switches which is how old bobcat works anyways. If I am able to swap connections and it works that will verify my thumb wheel is junk. I took handle apart and the thumb switch it has a magnetic sensor that looks to be broken and was full of all kinds of crap. Apparently I cannot buy just the switch they make you buy the entire handle to the tune of $800... I will exhaust all options before doing that
Update: As I said in my last reply, I switched the plugs for the solenoids for circuit a and b and confirmed its either the wiring or the actual variable thumb wheel thats bad because the circuit I need to work does in deed work now with the right hand side buttons next to the thumb wheel. And the other circuit that was controlled by the buttons now doesn't operate with the thumb wheel. This is fine for now or maybe ever as the grapple works fine with the buttons to open and close. I am sure when I need to use high flow attachments I will most likely want the variable control over the on/off momentary actions of the switches. I also have a low flow brush mower that runs 15gpm that I should be able to operate now as well, I am pretty sure I can set that circuit to hold on for the brush mower so I don't have to hold the button the entire time. If anyone knows of a way to get a new switch only that I can wire in that would be awesome. Its a 4 wire POWER, GOUND, SIGNAL, and CALIBRATION are their use in the schematics. I can't see me dropping $800 for an entire new joystick handle just because of a switch. As I said it seems to have a sensor with a magnet and the little circular magnet appears to be broken as if it was a full circle and it is only 1/2 circle now so the sensor isnt picking it up. Thanks for the quick help guys. I also purchased a pdf manual online for $39 which helped me get an idea of the system and how it works
You can check the function of those rare earth magnet switches. Your multimeter just needs to be able to read duty cycles. I don't spend a lot of time trying to diagnose the switches anymore. Just about any time I encounter a UFO problem on a cat with one of those I have taken to just replacing the handle. I actually cannot remember a single time in the last dozen years that that has ever backfired on me. But my clients priority is to get it fixed correctly and promptly, not cheaply. That being said; I would love to find a source for replacement thumb wheels. I have a corner in my tool room filled with cat joysticks that I label the specific failure on just to use as diagnostic tools on the next one. It would make my day to be able to save a client three to twelve hundred dollars by being able to resurrect one.
Congratulations on being one of those who do. 99% of queries related to High Flow are from folks who have no idea that the electrics need to be jumpered before the HF will engage on attachments without an electrical connection.
Nige I have the same problem, my serial number is *CAT0248BJSCL00969* can you help me? thanks in advance
Like post #4 here? CAT 287B high flow not engaging Hi I'm having problems getting my high flow circuit to work on my CAT 287B. Tested solenoids, checked wiring from solenoids to ecm. Checked fuses, power and ground. If someone by chance has a wire schematic and test procedures would greatly appreciate it. It has a ground force tree saw... HeavyEquipmentForums