Bill. You've made some wrong assumptions here and have multiple issues. You presumed that the two traces that were bridged caused power to be sent to the deck making it work all the time. In reality, my guess is that instead, the opposite is happening. Power to the radio and amp functions probably resided on a trace that was either weak or broken. The previous owner or repair tech decided that the easiest way to restore power to the amp was to bridge those two power traces; one to the amp/radio and the other to the deck. The bridged solder pads was likely done to restore power to the amp/radio, not to power the deck. Now that the bridged solder pads are restored, you should backtrace by manually following the board with a DMM to ensure that you don't have a nearly broken wire, bad solder connection, bad trace, etc. That is the power rail and needs full voltage. The deck appearing to fix itself when you desoldered the bridged connection was probably a coincidence. Normally, the deck receives full power at all times anyhow. The motor switching is all done at the deck and not at the main PCB. Just a bit of warning: You can check poor connection by either checking resistance (non-powered) or voltage (while powered up). The problem is that if a connection remains with a hair thin trace, a resistance check might show continuity since the current going to/from the meter is very small. However, with a large current draw, the connection might fail to provide full voltage due to inability to supply the required current. In this case, you may have to check using voltage function since it's a more reliable indicator of the quality of a trace under load. I can't tell you the exact problem spot where the failure is occuring. But it's how I would work this issue. The rest is up to you. Also suggest you aggressively clean/check the function selector switch. It's internal contacts might've failed.
Service manuals are rarely ever helpful with mechanical deck issues so that's something you just need to work through on your own. You are the one with it, and the one that gets to watch the action of all the gears, levers, etc. I think Docs may be pointing you in the right direction with the lever and if I recall, I also had to work that area a bit to make sure the gear and lever were properly aligned. I suggest you remove the lever and make sure that it's not binding. It needs to float freely and don't use grease either since while it reduces wear, will add drag to a lever that is very sensitive to any sort of drag. But I'm just guessing. My big ben is already reassembled and put away so I can't be of much help. Bad memory and all, you understand.
Traces don't bridge themselves for no reason. Somebody did this as a redneck way of "fixing" something. Just remember that in 98% of the boomboxes, decks "always" receive power 100% of the time. So it wasn't likely done to jury rig the deck which already had power.
