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    BOBCAT T770 low voltage issue AGAIN

    UPDATE....problem solved. Bad Gateway Controller. I called Bobcat of Asheville yesterday & spoke with the service rep. I explained the issue & my thoughts on it being a bad Gateway. He agreed that seemed likely. They had a new gateway in stock & amazingly had an open slot to send their service...
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    BOBCAT T770 low voltage issue AGAIN

    Most likely from Bobcat. unless we can find one from a reputable source for a better price. Possibly even a used one. However, if it still has to go to Bobcat for programming then it wouldn't be very cost effective to purchase one other than for future diagnostic/troubleshooting issues.
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    BOBCAT T770 low voltage issue AGAIN

    So the diagnostic analyzer from Bobcat would not be able to program the new Gateway Controller? From what I've seen it can be used to update everything on the machine. Of course the current software would be required. To program a new/blank unit would require proper software as well, so if...
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    BOBCAT T770 low voltage issue AGAIN

    Ozarkag, when you say the mainframe controller, are you referring to the ECM or the Gateway Controller? I contacted isocell. Unfortunately they don't work on the two plug ECM which is the one I have, nor do they work on the Gateway. I had the ECM and Gateway controller out, checking...
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    BOBCAT T770 low voltage issue AGAIN

    Great! I'll give them a shot. I'm going to spend a bit more time on it as soon as the weather breaks. I'm learning more about the CAN communication & unless I find anything obvious I believe it very well may be the controller, as you said. I'll update when I figure something out.
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    BOBCAT T770 low voltage issue AGAIN

    Thanks for the reply, ozarkag. That's what I'm thinking. I wonder if the controller can be sent off for testing without being on the machine? I'm really far away from the nearest Bobcat dealership/service shop. It has less than 400 hours on the machine.
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    BOBCAT T770 low voltage issue AGAIN

    One other thing I noticed. Upon shut down, when the display was showing 6.8 volts, when I switched the engine off, for a brief second just before the screen went black the voltage jumped up to 10 volts . Not sure if that indicates/means anything.
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    BOBCAT T770 low voltage issue AGAIN

    Hey all. Had a similar issue with this machine a couple years ago. I eventually found a couple of issues (bad connector pins on cab harness & corroded mega-fuse connections) and up until now it's been running well. This time it's very similar except it doesn't loose all cab power. Basically, it...
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    BOBCAT T770 Switched Power Output Failure

    Understood. I believe the majority of the issue is in the three multi-pin connectors that run from main frame to the cab/controls, etc. Yesterday evening, after ANOTHER afternoon of heavy rain/T-storms, I went through them one last time. I applied dielectric grease to each individual pin, just a...
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    BOBCAT T770 Switched Power Output Failure

    I believe Txhayseed is spot on about the wire harness. It rained all night & all day today. I went up the hill to drive the Bobcat down to base so I could work on it next to the house. I figured it would take several attempts as I could only run a couple of minutes before the power loss/low...
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    BOBCAT T770 Switched Power Output Failure

    UPDATE: Well, I've made some progress but still not there. It will crank right up & run just fine, but the gauge & display show LOW SYSTEM VOLTAGE so the controls are non-functional (except after sitting overnight...bizarre. Read below for description )The alternator is charging at 14.7 on the...
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    BOBCAT T770 Switched Power Output Failure

    Txhayseed, thank you! for the information & insight. It gives me a lot more useful ideas on how to move forward now. Another thing, based on what I've learned from you about these Bobcat wiring harnesses, it may very well explain another issue that happened a month or so ago. The machine was...
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    BOBCAT T770 Switched Power Output Failure

    I'm at a loss & need some help! I will be as descriptive yet brief as possible but, it's still going to be fairly long. I hope somebody can guide me through this. 2017 Bobcat T770. Deluxe set up. About 310 hours on machine. A few weeks ago right before shut down code M7028 SWITCHED POWER OUTPUT...
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    Kubota kx121 cranks but won't start

    I've tried the 10 second on/off key/GP routine several times...no difference. Air filter is OK, have tried with AF removed as well. I'm going to remove the GP's again & instead of ohm testing will hotwire each plug to visually see if functional. This was recommended by the "tech" at the place...
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    Kubota kx121 cranks but won't start

    The service manual would at least help guide me through the hydraulics, etc. I did try the switch but it doesn't function while cranking. I disconnected the quick-release fittings to the thumb lines & it cranked better but still too slow without manipulating the blade to release pressure. There...
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    Kubota kx121 cranks but won't start

    Without the service manual (on the way, gonna be a bit) I'm just tinkering. I did get it to turn over as fast as any engine, gas or diesel I've ever heard. The new battery & rebuilt starter are super. It should have started. It was blowing rich black smoke out the exhaust. The thumb had bled...
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    Kubota kx121 cranks but won't start

    I believe you may be on to something here. I'll check into the thumb valve in the morning. The thumb is controlled with a rocker switch on the joystick. The connectors I unplugged were all to do with the hydraulics. I unplugged four one at a time that were connected to valves and/or solenoids on...
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    Kubota kx121 cranks but won't start

    After I checked the fuel shutoff solenoid today (it was 2 wire not 3 but I tried it unplugged anyway, no go) I checked for an aux like you posted. I couldn't find anything that would indicate that could be it. I do recall though, last week upon first attempt to crank after installing battery...
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    Kubota kx121 cranks but won't start

    It shuts off with the key. I installed the rebuilt starter today & same issue. It reminds me of an automotive engine with the timing too far advanced...if I had to describe it. I charged the battery prior to attempting to crank it. My digital charger states 90% capacity/FULL. I still feel that...
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    Kubota kx121 cranks but won't start

    Welder Dave, Got it on the starting fluid. I've rarely used it throughout my life anyway but my friend kept insisting & it is his machine so I finally relented. I did use it very sparingly, but no more. The priming knob is not present on this unit. It has a crimped non-movable cap where the knob...
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