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John Deere 35C backup alarm won’t quit

digger242j ยท 2018-11-17 07:48

I spend a lot of time on a John Deere 35C mini ex. Normally, when travelling either direction, the backup alarm should sound. When there are multiple pieces of equipment moving around, it becomes part of the background noise. Last week, as I was digging, I began to notice a backup alarm while I was digging. Eventually, I asked the laborer, "Is that this machine?" He said, "Yeah. It sounds every time you swing." I paid a little better attention to it then, and found that to be true. Pretty soon, it was sounding any time I used any function. Now sometimes it even continues when the machine isn't doing anything. My concern is not so much that it's annoying, but that it might indicate some other problem. I don't know what specific mechanism activates it, but I can imagine that there's a switch in there somewhere that closes when it senses the hydraulic pressure in the travel circuit. Could this constant sounding of the alarm be a symptom of something like a leak in the swivel that's allowing the pressure of *any* function to activate the alarm? Thanks in advance for any insights...

Replies9
  1. #1mg23612018-11-18 05:57

    There are 2 switches in the propel in the propel pilot controller under your feet. They send a signal to propel alarm controller. The controller turns the alarm on. It may sound simple but make sure one of your travel levers is not partially sticking and not returning completely to neutral. It can turn on the alarm before the machine actually moves.

  2. #2digger242j2018-11-18 07:16

    I haven't noticed any stickiness in the travel levers, but I'll take a look at that. Thanks.

  3. #3Natman2018-11-21 22:29

    The first thing I did to my Kubota U-25S was to put inline a switch to defeat the travel alarm. Then I clearly labeled it as such "travel alarm defeat switch". I just found the beeper, and put the switch in the hot lead to it. I consider myself an adult, and competent enough to remember to turn it on IF and WHEN I'm working around others. Working on my own property, by myself, no thanks. I also have a backup alarm defeat switch on my 30 ton boom truck, no need to subject my rural neighbors (1/4 mile away) to it when I bring it up to my home shop for an oil change and back it in the shop on a Sunday morning! On any job site it's always ON for sure, I just don't feel the need for those things when working at home.

  4. #4digger242j2018-11-21 23:25

    There is a button to make it stop, labeled "S10 Propel Alarm Cancel switch" in the schematic mg2361 posted, and it works to stop the alarm, but only until you stop moving the machine. Start moving again, and it starts beeping again. In this case, it starts beeping again as soon as you use any function, and it's just not practical to keep pushing it while trying to dig. I did check the travel levers and there is no stickiness apparent in either one, in either direction. Back to the schematic--I see the "B16 Right Propel Pressure Sensor", and "B15 Left Propel Pressure Sensor". That leads me to believe that my original suspicion is a possibility. Something must be providing pressure to one or both of those switches when any hydraulic function is used, mustn't it?

  5. #5Tones2018-11-22 06:29

    Digger, the simplest diagnostic tool for issues like this is wire cutters.

  6. #6digger242j2018-11-22 08:46

    Well, if it's an electrical issue, wire cutters might be the simplest remedy, but a hydraulic issue seems like it'd be a whole lot more expensive, and to fix that, wire cutters aren't going to cut it... (Pun intended.)

  7. #7crane operator2018-11-22 08:57

    I would think if you are getting pressure at all to the "travel" circuit or any other function bleed by, you are going to start to see it in the machine. That is to say, you'd see the tracks start to jump when you are doing some other function, or you will have bleed by from one function to another or functions running slowly because they are bleeding by to return to tank. That's been my experience with crane hydraulic swivels when they start to go bad. The only way you are going to figure out the issue is to get out a electrical tester, and do a little trouble shooting, find out if the travel solenoids are sending out the bad signal, or if the controller is bad, or you have a backfeeding issue from something else and its showing up by making the travel alarm go off.

  8. #8mg23612018-11-23 05:51

    If you use a volt meter back probe the center wire (should be terminal 2) on the pressure switches to see which one is turning on the alarm (if it is turning on the alarm). Plug a gauge in place of the pressure switch to see if there is actually pressure there activating them. That would eliminate hydraulics or not.

  9. #9245dlc2018-11-23 08:27

    Just find the alarm itself there should be a clip that plugs in to it. Unplug it problem solved. Also pull up your floor mats and clean out around the foot pedals we work in mud quite often cleaning ditches and other mucky work and often have to pull up the mats to keep crud from building up under and around the pedals.