And this would surprise you, it being a Gen II and all?
But seriously, Don...something definitely whacky goin' on in the electrical system to have such wildly different readings between the OEM harness and a straight shot from the RR to the battery.
Keep up the detective work. You're gettin' closer.
Oooh, I knew the cheap shot gen2 comment was coming, so I put on my condom and got fluffed for yah Howie! Let's see, who was out front on the 17 mpg instantaneous, the ignition switch, deer strike, altitude sickness, and now low charging? It's a bitch being a leader,
See updated comments below..
Good job and thanks for sharing. Mine used to show 14.1 on datel up until 2 years ago. This spring I replaced the battery and no joy. I see low to mid 13's like yours did. It still runs OK so I haven't got serious about diag, but I'll be watching this thread.
I'm sure Alan or Fred had you check, but have you done a voltage drop test between the RR and battery? Maybe I'm calling it the wrong thing. I'm not saying to measure volts at each spot to see the difference. You put one lead on the RR wire at the RR and the other on the battery. Do this on both the pos. and neg, side. With the meter set on volts you should see 0 ideally, less than 1 volt is OK. This test is checking the condition of the wiring between the 2 points. If the wiring is poor, or too small then voltage will go threw the gage that you have hooked up in parallel. If all is OK no volts or very little will go threw the gage.
From the results you got bypassing the harness that says that volts would be going threw the gage in the test. now you can do the same test, but do it on every leg or part of the pos. side to find the culprit. You can check every connector and piece of wire this way.
RR, you're on the right track. I've done voltage drop tests and resistance checks across both legs of the charging circuit. Resistance says 0, voltage drop indicates not. Just like Prof IonBeam said. Trust the Prof, trust me.
Tonight I tested the ground leg by removing it from the battery and placing it on the frame in various locations - near the steering head and way back on the stupid swing arm. Great output - note the 'external harness or EH, in place).
I then removed wiring from all but one connector near the main fuse to check crimps, corrosion, etc. All looked great. Even tried to connect RR + to wiring near main fuse but had no way to connect with the large lug up there.. So scrap that test.
Maybe the connector at RR output? Cut if off, crimped two female connectors (no solder, but good clean crimp), and yes, the VDC a battery improved, very much so... but not to same level as direct connection to battery from RR.
This, me thinks, is the big clue. Any slight resistance... will cause voltage drop. Even the difference between a freshly crimped connector and one soldered. The OEM has several crimped connectors along the path. When I see guys on Ebay and Jim at Eastern Beaver selling kits that go from RR direct to battery with inline fuse, with kits for numerous bikes, that tells me something.
At this point, I say screw it. I'm done trying to find the smoking gun. I'll post up another thread asking if anyone has spider harness and check local dealer, just to see if my theory that somewhere, there is another junction, not listed in FSM schematic, just like my 61 Chevy did to me.. Bastids..
Another thought is that many times new, fresh, perfect as can be production looms decay with time. Marginally built to save $$, soon enough the decay and issues arise. Just like the FI harness on a 6-cyl Jeep Cherokee I once owned. Not a single root cause, but multiples leading to the aggregate.
Other thoughts, observations..
What a wonderful learning experience this has been! I actually understand how permanent magnet load shedding alternators work.
I learned the wiring harness for a gen 2 FJR,and every page of FSM wiring schematic. :blink:
I learned Professor Ionbeam is always right.. :huh:
I learned that 14.2 volts on a gen 2 FJR is possible at the battery, 14.1 with HID's, fans on, hi beams on is possible. :yahoo:
I learned that my stock regulator has higher Vdc output, runs cooler at idle and hotter than upgraded RR at 5k rpm and heavy load.
Conversely, the upgraded RR runs hotter across all loads and rpms, and has marginally better current output.
I learned the upgrade RR uses Mosfets, not diodes like the OEM RR, and will shutdown rather than burn out if design parameters are exceeded.
I learned the OEM FH012AA has been updated with a FH020AA.
I learned
taking videos of the testing process is invaluable - reviewing the videos later proves testing technique and discerned values.
I learned I can get absolutely KrZy with diagnosing problems.
Questions I still have -
What does it mean when Professor IonBeam says "Given a bike with it's history",
and KaitsDad says "You're now my favorite FJR problem child. :huh: "