Testing The Charging System
- Thread starter glider.
- Start date
J
Jack Klarich
Guest
Testing for shorts to ground
The best way to test for shorts to ground is with a 12-volt test light. Sometimes an ohms meter will not pick up a short to ground. The light test is better.
Using a standard automotive test light, connect the ground clip to a good ground. Test the light by touching the probe to something positive such as the positive battery terminal. The light should light indicating you have a good ground. Now you are ready to start the test.
Unplug the regulator from the stator and start the motor. Probe each stator pin with the test light one at a time. If the bulb lights when connected between any of the stator plug pins and ground the stator is shorted and needs to be replaced.
If you get proper AC voltage and the stator is not grounded (no light) the stator and rotor are good. At this point you can assume the problem is either a bad connection between the regulator and the battery or the regulator is bad. Try This
I need help please!!
This summer I had an electrical gremlins attack. A 40 year certified Harley Davidson mechanic is working on the bike.
Starting this year:
Over the winter the original battery was replaced with HD.
May- the crankcase position sensor went bad (replaced)
When I picked up the bike and during a short ride the "low Battery light" and engine light came on and off in about 2 minute increments until I got it home.
Mechanic replaced stator/regulator and checked all grounds. Voltage checks were good. Putting out 12.8 at idle and 14.4 at rpm.
I picked the bike up and had ridden about 40 minutes when the lights came back on.
Returned bike to mechanic and he said regulator was toasted. He put new stator, new regulator and replaced the battery with a new battery as it wouldn't accept a charge past 11 volts. He thought the battery was the original issue at this time.
Picked bike up and rode about 45 minutes when the lights came on again. Regulator was cold to the touch when I made it home indicating it was fried again.
I'm open to any ideas....please
This summer I had an electrical gremlins attack. A 40 year certified Harley Davidson mechanic is working on the bike.
Starting this year:
Over the winter the original battery was replaced with HD.
May- the crankcase position sensor went bad (replaced)
When I picked up the bike and during a short ride the "low Battery light" and engine light came on and off in about 2 minute increments until I got it home.
Mechanic replaced stator/regulator and checked all grounds. Voltage checks were good. Putting out 12.8 at idle and 14.4 at rpm.
I picked the bike up and had ridden about 40 minutes when the lights came back on.
Returned bike to mechanic and he said regulator was toasted. He put new stator, new regulator and replaced the battery with a new battery as it wouldn't accept a charge past 11 volts. He thought the battery was the original issue at this time.
Picked bike up and rode about 45 minutes when the lights came on again. Regulator was cold to the touch when I made it home indicating it was fried again.
I'm open to any ideas....please
Just a quick tip. If you are near Harbor Freight, many times they have coupons, and offer a free DMM (Digital Multi-Meter), which is suitable for most basic electrical tests you may need to use.
Volts (electrical pressure), just bridge the test leads to your connections (use caution not to allow either lead to contact).
Ohms (electrical resistance) just make sure no power is active in circuit to be measured (DMM internal battery provides source).
Current (electrical volume) is for low current use (10 amps max. typically) so it's use is limited and putting meter in series means all energy is directed through the instrument so use caution here too. :hii
Volts (electrical pressure), just bridge the test leads to your connections (use caution not to allow either lead to contact).
Ohms (electrical resistance) just make sure no power is active in circuit to be measured (DMM internal battery provides source).
Current (electrical volume) is for low current use (10 amps max. typically) so it's use is limited and putting meter in series means all energy is directed through the instrument so use caution here too. :hii
jimbo bones
New Member
I have a 03 roadking flhpi that had a bad reg. and I replaced it. it is charging now but im getting 18v at higher rpm.lights go bright and flashers come on . sometimes it will show low fuil when full and want idle or it will idle to high. whats up with this.also speedo quit working
J
Jack Klarich
Guest
18 volts is way too high for voltage, check the voltage at the battery with a known good meter before you proceed
Guythunder
Member
Re: Bad Reulator Or Not
I have been having this charging problem on my 1991 Fat Boy. I have a volt meter from Kuryakyn on my bike to show me if my charging system is working right. But in the last few days while ridding the meter would go all the way over in the red saying that there is a problem with the system, But it wont do this all the time. Will a Regulator do this sometimes good and some bad.? I have done all of the other testing that needed to be done and everything else checks fine, I had the meter in the red today and while it was there I checked the volts coming from the regulator to the breaker and it was putting out 19 volts, But then later when the meter was in the green again where it should run I tested the volts at the breaker again and it was 14 volts. So I would think that it is the regulator with a intermediate problem.
I have been having this charging problem on my 1991 Fat Boy. I have a volt meter from Kuryakyn on my bike to show me if my charging system is working right. But in the last few days while ridding the meter would go all the way over in the red saying that there is a problem with the system, But it wont do this all the time. Will a Regulator do this sometimes good and some bad.? I have done all of the other testing that needed to be done and everything else checks fine, I had the meter in the red today and while it was there I checked the volts coming from the regulator to the breaker and it was putting out 19 volts, But then later when the meter was in the green again where it should run I tested the volts at the breaker again and it was 14 volts. So I would think that it is the regulator with a intermediate problem.