Howdy all! This is my first post and I’m hoping for some wise technical advice!
I have a 2001 FLTRSEI2 with 42k miles on it. Voltage meter reads 12vdc at idle but gets up to 14vdc at 2800 rpm. I replaced the stator as recommended by the local hd shop. No change. I’ve replaced the voltage regulator twice. No change.
I stumbled on a charging system troubleshooting procedure on the J&P Cycle website which included a voltage regulator bridge rectifier diode check. I’m including it along with my readings. I’m looking for a sanity check from anyone who knows more than to see if this makes any sense.
1. Battery Test
The battery needs to be a fully charged battery and load-tested to ensure proper readings. Standing battery Voltage should be 12.5-13.2 DCV.
Mine: 12.7 vdc
2. Charging System Voltage Test
Start motorcycle, measure DC Volts across the battery terminals (you should have a reading of approximately 13.2-15 DC Volts).
Mine: 14.1 vdc
3. Check Connections/Wires
Inspect the regulator/stator plug, and check the battery terminals for connection/corrosion. If everything seems to be in order, move on to NO. 4 below to determine if there’s a failed component.
Mine: nothing out of the ordinary noted
4. Stator Checks/Rotor Check
Each of the following tests isolate the stator and rotor. If the AC Output test fails and Resistance Check and Stator IB Test pass, then the rotor is at fault (Pull primary covers and inspect rotor for damage).
AC Output Check:
Unplug the regulator plug from the stator. Start motorcycle and change Voltmeter to AC volts.
Probe both stator wires with your meter leads. The motorcycle should be putting out approximately 18-20 ACV per 1,000 rpm. (Reading will vary depending on system, check service manual specifications)
Generic Specs:
22 amp system produces about 19-26 VAC per 1,000 rpm
32 amp system produces about 16-20 VAC per 1,000 rpm
45 amp system produces about 19-26 VAC per 1,000 rpm.
Mine: 45 amp system: 22vdc@1000 rpm; 44vdc@2000rpm
Stator Resistance Check:
Switch your multi-meter to Ohm x 1 scale. Probe each stator wire with meter leads and check resistance on meter. Resistance should be in the range of 0.1-0.5 Ohms.
Generic Specs:
22 amp system produces about 0.2 to 0.4 ohms
32 amp system produces about 0.1 to 0.2 ohms
45 amp system produces about 0.1 to 0.2 ohms
Mine: 0.1 ohm
Stator IB test or Ground Check:
Switch your multi-meter to Ohm x 1 scale.
Probe each stator wire with your positive lead on multi-meter and the negative to ground.
There should be no continuity to ground on either wire. If there is continuity to ground, your stator is shorted to ground.
Mine: infinite resistance to ground. I checked several good ground points to be sure.
5. Regulator Test:
Each of the following tests isolates the regulator only, so if any of these tests fail, the regulator is at fault.
Fwd/Reverse Bias Test/Diode Test:
This check is for testing the diode function to ensure it is regulating the AC current for the stator into DC current.
Switch multi-meter to Diode Scale.
Place your multi-meter positive lead on each AC output wire.
Place your multi-meter negative lead on the battery Charge wire.
The meter should read voltage typically around .5 volts.
Mine: infinite reading
Next, switch your multi-meter leads putting the negative lead on the AC output wires and the positive lead on the Battery Charge Wire.
The reading should be infinite.
Mine: 0.525 vdc
With your meter on the same setting, place your multi-meter positive lead on the regulator ground wire or to the regulator directly, and then place your meter negative lead on the AC output leads. The meter should read typically around .5 volts.
Mine: 0.5 vdc
Next, switch your multi-meter leads putting the negative lead on the regulator ground and the positive lead on the AC output wires.
The reading should be infinite.
Mine: infinite
So my diode check measured the exact opposite of what should have been read per this procedure. I checked to ensure my Fluke was set on diode mode and ensured the test cables were correctly in place.
The stator is fine yet I keep failing voltage regulators. In my poor defense, I have been purchasing low dollar Chinese made crap. I just don’t want to purchase a $150-$200 unit, have it do the same thing, then not be able to return it.
And to throw another wrinkle into this mess. I stumbled across a thread that discussed the difference of the stock 1-phase charging system and the 3-phase systems. In a nutshell the 1-phase systems drop to 12vdc at idle speed by design then pick up to 14 vdc when off idle. This is apparently considered normal. I have the 1-phase system
So now I feel like I’ve been chasing ghosts. Is my regulator fried based on the J&P Cycle test or is it working properly? That’s what I really want to know.