Caterpillar 257 ECM

[buytheplace]

My cat skid steer bombed out yesterday. The parking brake light started flashing on and off. Cannot turn it off so the machine won't move. The hydraulics do still work however, which is puzzling. Towed to the dealer today. They say the ECM needs replacement, a $700 plus repair. Any advice?? Is this logical?? How do I know that it isn't a simple brake control switch?? Help!! Thanks

 

[Fishfiles]

Quote : "Any advice??" --------Reply : "trade it in !" ----------I am really not up on the Cat 257 electrical system , the parking light flashing it could be tring to tell you something , the Bobcat flash is a marse code , dot -dash , you can count the flashes and look to the manuel and it tells you what could be wrong , I would think your problem is a sensor , switch , relay , solinoid , coil or the wiring in between

 

[19road_runner68]

I'm not a CAT. mechanic, but I do turn wrenches in the automotive field. After working on car electronics for over 10 years now, I wouldn't doubt thier findings. I'm loooking at the cat. service manual for a 257 and the brake control switch does run through the E.C.M. If it was me, I would check the wires from the switch to the ECM for an area of wiring that may have rubbed through, and now the wires are touching the frame of the tractor. This is called a short to ground. If that's not the problem, I would jump the switch with a fused jumper wire and look for results. If that doesn't work, I would run power to the park brake solenoid to make it work, eliminating the computer all together. that doesn't fix anything but it should get you working again.