With my 2012 Heritage Softail Classic, my battery was dying on the road twice a few days ago. I bought a new battery, but I was told that my bike cutting out could be the regulator (much bigger issue....?). I need to catch this early.
My question is: how do I tell if my regulator is the part of the bigger problem? If it keeps stalling with the new battery? Any other clues to consider before the regulator goes?

 

Start here and follow the testing sequence. Then report back with your findings.

Also check your main fuse & ignition switch.





BATTERY, ELECTRICAL & CHARGING ISSUES:

A good quality Volt Ohm Meter will serve you well and they are not that expensive.

This should help you out and explain the procedure in a manner that is understandable.

See:

https://www.hdforums.com/forum/elect...sting-1-a.html

https://www.hdforums.com/forum/elect...sting-2-a.html

NOTE:
The above information, while credible, is worth what you paid for it and should not be considered gospel.
Do due diligence, research and have a H-D Field Service Manual before working on your bike.
You will probably have many opinions and suggestions presented; make sure you research the person providing the helpful information as there are some who provide good information that is useful and some who speak out of other orifices with gibberish. You will figure out this quickly.



1. Make sure the battery is charged good with a battery maintainer or battery charger.
2. Let battery sit for a couple of hours and see what the static voltage is, should be 12.4 VDC or above.
3. Then see what the voltage drops to when starting - should be above 9 VDC, if it drops lower the battery may be bad or you have too much current being pulled by the starter.
4. Get the battery load tested to see what the current Cold Cranking Amps (CCA) are and compare to the CCA listed on the battery or on line battery specs for that battery.
5. If your volts when charging are 13.7 then your charging system should be okay.
6. Check all battery connections and grounds both at the battery, frame, and starter.


Harley Davidson Charging System description and testing

Description:

The charging system consists of 3 major parts:

1- An Alternator that generates single phase or three phase alternating current, (AC).

The Alternator has 2 parts:

Rotor:
Attached to the primary side of the crankshaft. The Rotor has a series of permanent magnets and rotates around the Stator at engine speed.

Stator:

Attached to the crank case and has a series of wound wire coils. The Rotor fits over the stationary stator. As the Rotor spins around the Stator the rotating magnetic fields induce Alternating Current in the stationary coils. The Stator’s coils are arraigned so the AC output is either single or three phase.

2- Voltage Regulator, (VR), rectifies the Alternating Current, (AC), from the Stator to Direct Current,(DC), and limits the voltage output to a value close to 14.5 V DC.

3- Battery, a 12V rechargeable storage device used to supply power to the bikes electrical circuits.

As shown in the schematic the charging system includes insulated conductors and connectors carrying current from the stator to the VR through the main fuse to the starter and on to the battery positive. The VR negative lead and the battery negative lead are both connected to Chassis ground.

This system can be checked with a few easy tests using a digital or analog Volt–Ohm Meter.

Testing:

Connectors and cables should be checked and cleaned first. Loose and corroded connectors, terminals and grounds can cause high resistance, impeding current flow. Check cables for broken or rubbed insulation and check continuity to make sure the conductor is not broken inside the insulation.

Coating connectors with dielectric grease will keep moisture out and reduce corrosion.

Use the schematics in the HD Electrical Diagnostic or Service manual to determine the location of additional connectors.

Battery testing:

First check and clean battery terminals, Battery cables and ground connections. To check cables, disconnect one end and Ohm out, wiggle while testing. Cables can and will corrode and the evidence can be concealed under the insulation.

If you are unsure of the battery’s condition charge it fully and take it to an auto parts store and have it load tested.

Voltmeter test:

Connect voltmeter positive to positive terminal on battery and voltmeter negative to battery negative terminal.

12.7 v = 100% charge

12.6 v = 75%

12.3 v = 50%

12.0 v = 25%

11.8 v = 0%

Watch the battery voltage when you start the bike, if a fully charged battery falls below 9.6 volts it’s time to replace it.

If a well charged battery runs down if the bike sits for a short time perform a current draw test. Set your meter to read 10 amps current. Pull your main fuse and insert the meter leads. Here’s a list of components and what current they will draw in milli amps, 1/1000 of an amp) from the 2015 manual:

LHCM 0.5

RHCM 0.5

Speedometer/ IM 0.5

Regulator 1.0

ABS 1.0

BCM 1.0

ECM 1.0

Security Siren 20.0

Radio 0.5

Amplifier 0.5

CB Module 0.5

If the Battery passes all tests check the charging system.

Charging System Testing:

Volt meter set to DCV 20V scale or higher.

With the bike in neutral and voltmeter attached to the battery, start the engine and rev to 3,000 rpm. If the voltage measures 13V – 14.7V the charging system is operating properly. If less than 13V test the Stator first. If Greater than 15.5V test the Voltage Regulator.

Stator testing

Turn the bike off and disconnect the Stator from the Voltage Regulator.

Testing a 3 phase Stator, (A single phase stator is tested in the same manner but the plug will only have 2 sockets).

The end of the connector from the stator has 3 sockets. Set your meter to ohms and connect one lead to the battery negative. With the other lead make contact with the conductors inside each socket. You are checking for a grounded coil winding, each socket should show an open circuit to ground, no continuity.

Now take both meter leads and check resistance between each of the three sockets, 1-2, 2-3 and 1-3. The resistance should be 0.1 – 0.3 ohm.

Next check the Stator’s AC output. Set the meter to ACV 100V scale. With the Stator unplugged from the VR and the bike in neutral, start the bike. Run the bike at 2,000 rpm and check the Stator output between sockets 1-2, 2-3 and 1-3. The voltage should read approximately 32-46 Volts AC, for the 50 amp Stator. Stators with other Amp ratings will be similar.

If the Stator continuity tests to ground and Phase to Phase are good but the output is not the Rotor may be bad.

One other indication that the stator may be bad is if your primary oil smells like a burnt circuit board.

Voltage Regulator Testing

Voltage readings of 15.5V and higher:

Test wire from VR negative to battery negative, if less than 0.5 ohm replace Voltage Regulator. If resistance is more than 0.5 ohm check ground connection for corrosion and wire for damage.
If the output is less than 13V from the Voltage Regulator to the battery and the Stator output is good, disconnect the output cable from the VR to the Battery. Check continuity between the Voltage Regulator Positive wire and the battery Positive and the negative wire and battery negative. Repair or replace cable if needed. If the cables are good and the Stator tested well replace the Voltage Regulator.

 

Thank you CoolBreeze for the very detailed explanation!!! I will certainly follow your advice and directions.