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Electrical issues: Komatsu WB140 S/N F1000 range

morpheos137 · 2025-01-16 02:13

I had my backhoe sitting for several months last summer. Apparently mice got in the cab and under the hood and chewed the wiring harness / individual wires. I spliced and patched all the chewed sections I could find in the dash, side console, anf under the hood. However I am still getting blown fuses...and the most problematic symptom, is on occasion the machine dies suddenly while using the backhoe, particularly when swinging side to side. This is strange to me because there is no electric wiring in the backhoe arm. Maybe one of the swing cylinders or hoses to the cylinder is brushing against damaged wires under the cab. Maybe what's happening is the fuel shut off solenoid on the pump is shorting and closing while running. The machine seems to die quickly almost instantly and won't restart after because usually but not always a fuse is blown. Either fuel shut off/start enabling/instrument panel fuse. Anything else to look out for when trouble shooting?

Replies1
  1. #1HarleyHappy2025-01-16 08:11

    Just gonna have to find the damage and repair. Does it blow a fuse every time or do you have to wait for a circuit breaker to reset. Either way, it sounds like a direct short to ground. I‘m assuming that while it is swinging, somewhere a wire is moving by a hydraulic line or possibly the frame itself. Troubleshooting a wiring issue, is one of the most bang head things to do but when it’s found, generally you just start yelling and arguing with yourself.