First, thank you to those of you who gave suggestions about fuel lift pump. I did put in a universal pump. Bled system, started motor, and system light came on as well as what I think must be the collision alarm (single tone, loud alarm) and hydraulics won't work. No idea what happened. Only two wires in the area of the fuel pump were the two to the fuel pump. Nothing else was touched. Everything worked before the fuel lift pump wires broke. I am totally baffled. Coincidence? Murphy? Or did I do it somehow? Any first step ideas? ( I did not disconnect the battery when I hooked up the new pump - I'm confessing to transgressions that may be irrelevant - but worried that that may have screwed up something
Disconnect the fuel pump from the wiring harness and run it direct from the battery with a separate fuse. Then see what it does. Are you sure it was an electric fuel pump that you took out?
Thanks for the reply. Yes, electric in-line pump one red wire, one black. Will try your suggestion. Any suggestion on size of fuse for this?
15 or 20 will be fine. It's just for testing purposes.
OK. Will try it and let you know how that works.
Finally got a chance to do what you suggested. Other calamities plus a bad case of frustration procrastination. Nothing changed. System light still on and single tone alarm. Did get a troubleshooting list from Hitachi manual, so will do my best to work through that. If you have any other ideas, I'd welcome them.
Maybe an electrical connector got bumped/pulled enough that it's not connecting anymore?
Cab impact safety system?
Would the cab impact safety system be the same as the collision prevention system? I'm having a hard time deciphering the Hitachi manual; it does give a troubleshooting "tree" but terminology is vague for a novice. Under the Collision Prevention System section - and symptoms do sound like that would be the system in question - it refers to a system failure indicator, which I'm assuming is the system light on the dash - and if it is on (IT IS ON) with the engine running then to go to to a diagnosis by buzzer and indicators. It says that if there is a constant sound (AFTER STARTING THE MOTOR OURS COMES ON - GOES OFF AFTER A COUPLE OF SECONDS - COMES BACK ON AND STAYS ON) which I am interpreting as a constant sound as it does not go off after that lapse of a second or so - then to check the "system deactivation indicator" (elsewhere there is a reference to a controller and controller LED) This I take it, is an LED that is viewable with a mirror under the operator's seat. (THE RED LED BLINKS) Again, here is my confusion. They say if the indicator is off (LED, under the seat) then it's a failure in the Angle Sensor circuit. So that option as a diagnosis is shot, I guess. Elsewhere in the "tree" it says that if the indicator is blinking, then its a failure in the controller - but the preliminary steps don't match our situation but that's the only reference to a blinking indicator. Boy am I confused. It's a head scratcher. Delmer, checked every electrical connector we could find. Checked fuses, too.
I think so... it's basically supposed to prevent you from slamming into the cab with the bucket when the offset boom is shifted left.
Just to fill you in. Four guys, all w/ excavator experience, were here yesterday. One of the times the excavator was started, it started to gain some functions blade, some bucket movement, some arm movement. Then the alarm went off for a bit and there was more function. After several restarts and partial function, during which the alarm came back on and on some starts the hydraulic functions were lost again. They didn't think it was the brain/controller. One guy (previous owner) thinks it's some flukey electrical connection. One guy say he thinks the fuel pump - in-line universal one - is causing it. That's where we stand now. The other two guys? One just shook his head and the other decided to just drink beer Any thought on the opinions?
I'm guessing bad angle sensor somewhere, or a wiring issue in the harnesses for that system.