Greetings Fellas. Working on this JLG 450aj and whenever the foot pedal is pressed it stalls out. I've read around some existing threads on similar machines and it doesn't seem like a solutions ever found. So I thought I would make this thread and see what we can come up with in 2020. The info I have to work with right now is that the governor appears to be working. There is power at the pedal, from what i am told. If power is added manually at the basket controls, with machine not running it seems to trigger some kind of relay, you hear a click...and then all power is lost for as long as it decides to stay out, could be 10 minutes, could be till the next day. If the common ground is removed from the foot pedal, depressing it will leave the engine running but now nothing works at the basket controls. That is all the info I have to go off currently, anyone have any ideas on how to narrow this down?
Do you by chance have a JLG Analyzer tool? You might be able to see if the foot pedal is interfering with another circuit. I have had a few instances where the main harness has gotten damaged. Typically occurs right at the platform, where it rotates. Either pinches it or repeated flexing damages the wires. It can happen at any pivot point though. Have you tried pinning out the harness from the ground module to the platform module? Continuity on each wire as well as for possible cross-continuity from an internal short in the harness?
Thanks for the response. We don't have a diagnostic tool but maybe that is on the horizon. I've replayed your info/suggestions to a friend and gave him a link to this thread. I'll report back if we find anything. Thanks.
check the voltage in the basket before and after you step on the foot pedal. That's always a good step 1 on these machines.
What engine ?