I just purchased a Kamotsu PC300LC-6. Machine has some electrical issues. after running for a short time the engine will be running at full throttle and shut down and bounce back and forth like the high idle is lost. It will run abit longer and then do it again. today it completely shut down and wouldn't restart. I waited a while and still wouldnt start. I wiggled the key switch hard and it started. Also while in error mode on the monitor Im only getting 101 and 102 errors which i dont believe to be any of the issues. While in monitor mode i am not getting the engine to read RPM under code 10, or pump pressure under 11 and 12 mode. I only see a readout on code 1. Could i have a bad monitor or more electrical issues? Could this be a bad speed sensor?
you might need to check with the fuse arrangement ,make sure they are all in good shape ,before continuing to inspect the engine governor motor, the governor motor angle sensor might cause that issue or the engine pump controller issue
Do you have an operation and maintenance manual? Have you thought of getting a service manual? The codes 101 and 102 just mean the battery has gone dead or been disconnected in the past. You can check the speed sensor with an ohm meter. They either short through, short to ground or have infinite resistance. If the speed sensor is bad, you should check the oil level in the damper case. The level plug is on the damper case below the pump. I've seen them over full and hot enough to discolor the paint on the damper case. This is the biggest reason speed sensors go bad. As I recall the pressure sensors are on the control valve inlets from the hydraulic pump. You can check them with the ohm meter as well. They also short through or have an open circuit. The governor control motor could be bad but usually when that happens they just freeze up. You can disconnect the harness connectors at the motor and check the movement of the linkages. There should be a slight resistance to movement. Make sure to disconnect the motor because moving it will induce a current that will go back to the computer and possibly damage it. The biggest issue I've had with throttle control motors on Komatsu excavators is with the wiring at the motor and at the harness connectors. Two common issues are the harness connector hangers and the muffler having a hole in it and blowing hot exhaust on the wiring and the motor itself. If the connector are not reinstalled on the hangers properly, the wiring can rub against the hanger cutting away the insulation and shorting out. The muffler issue speaks for itself. Good Luck!
The fact that it cooperated again with key wiggling suggests to me a possible problem with the ignition switch, do you have a service manual? I recently had to replace the switch in my machine and was able to confirm with a multimeter using specs given in my service manual. If you don’t have a manual, you’ll do yourself a huge favour by getting one.
I tend to find out what is wrong before buying parts. Why tear the console apart for something that more than likely was just a coincidence. I cost's only labor time to check items that are more than likely to be a problem. A key switch is very likely over $100 US and you are more likely as not to mess something up tearing the console apart trying to replace it if you haven't done it before.
That’s what I said... I didn’t say replace the switch, I said get specs from a service manual and test it with a multimeter. And frankly getting at the switch is far from an invasive procedure, if you can’t handle that then you’re going to have trouble fixing pretty much anything.
Keep in mind that many of the people posting here are exactly as you describe.
John refresh my memory. One of the dash 6 models 200/220 or 300 had a problem with the harness coming out of the clamp by the engine and it would short out.
I think it was both the Dash 5 and D6 PC200 and 220 on the two harness connectors for the governor throttle motor. The connectors were right under the muffler on the outlet side of it. Water would go down the stack and rot out the bottom of the muffler from the inside and then blow hot exhaust on the wiring and the connectors.
This is exactly why I pass up commenting on many posts in this forum.