Hi all, have a CAT 420E IT serial CAT0420ECPHC01054. Customer called saying that the self leveling feature on the bucket stopped working, I had assumed that he meant the "return to dig" feature. This machine has a single magnet switch on the right side, attached to an arm that goes about halfway up the cylinder. It doesn't have the roller switch and long armer that travels all the way up tp the cab. Anyway, this switch has 2 lights on it. One that I assume is power in was on and the other stayed off, no matter how near or far the magnet got to it. The magnet itself was busted up a bit, but I pulled it off the arm and the switch would not light up with it directly on it, nor with one of my stronger magnets. 3 wires going into it, tested for a change in continuity while bringing the magnet to/from the switch and got no change. Definitely have power going into it, as the "power" light comes on and I'm getting 13v at it. I assumed the switch was bad and am gonna replace the busted up magnet too. Waiting on parts to get in. Just wondering if this is the only sensor/mechanism that would have to do with controlling the "auto-level" or "return to dig" function on this machine. No other bars like the 420D has? I know the solenoid/connectors can go bad, just didnt wanna climb into the snow and test it under the machine until I get a new switch or at least learn if I am testing this switch properly? Anyone think that I am not attacking the issue correctly and have any tips? Thanks in advance!
You need an electrical schematic. Check your message inbox. The way those position sensors work is that the green light indicates the switch assembly is powered up and when the magnet passes close to it the yellow (I think) light also lights up to show that the switch has changed state. "When the magnet reaches the switch assembly it causes the switch to close. This allows current to flow through the electric circuit to the solenoid. The activated bucket positioner solenoid pulls the detent roller away from the tilt control lever. A spring in the pilot control valve moves the tilt control lever to the HOLD position. The bucket then stops at the correct angle for digging."
Okay, cool. If so, then I was assuming correctly. I has assumed it was a normally open switch, which is why I was getting power into it and not out of it. No matter how close I bring the magnet to the switch, it doesn't close it. I tested this with continuity also, incase the 2nd light was broken or something. Has 3 wires going into it. Assumed black was ground, 1 wire has 13v and the other wire has nothing. I had thought the magnet being broken was the issue, but I can't get it to change state with other magnets directly on it. Although, I did find out that on the harness side, 2 of the 3 wires have continuity to ground. So I'm wondering if that is wrong and one of them is pinched/cut and grounding out when its not supposed to be. An electrical schematic would be awesome. Checking messages now, thank you!