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Voltage Regulator?

TQuentin1

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OK guys. Hopefully NEWHD74FAN, Hoople or some of you other sparkies can help with this. When I tried to start my bike yesterday, I got nothing. Lights on the dash and radio worked, but no attempt by the starter to turn over. I have not been riding the bike for a couple of months, and the battery has been on the tender the whole time.

Today I pulled the seat off and measured the Vdc across the terminals. When I removed the tender, I watched the voltage drop continuously. Figured it was the battery, so I went a bought a new one at HD (holy cow, $165!!). On the way home I realized I should have tested the VR BEFORE buying the battery. So when I got home, I did check the VR. I did that by disconnecting the stator lead, removing the VR from the frame and check for any voltage from each pin to ground. Both pins show full battery voltage to ground.

So I took the battery back and exchanged it for a new VR. Installed that and then checked for any voltage drop from each pin to ground. SAME THING!! Battery voltage to ground from both pins.

What does that mean? Is this new VR bad, or is the testing described below in item #2 not applicable for these VRs?

Testing The Charging System - Harley Davidson Community

Any insight here would be especially helpful since we have been recommending that folks follow these procedures to test their electrical charging systems. If it is not correct for a certain group of VRs, we need to correct this.

Thanks,

TQ
 
OK guys. Hopefully NEWHD74FAN, Hoople or some of you other sparkies can help with this. When I tried to start my bike yesterday, I got nothing. Lights on the dash and radio worked, but no attempt by the starter to turn over. I have not been riding the bike for a couple of months, and the battery has been on the tender the whole time.

Today I pulled the seat off and measured the Vdc across the terminals. When I removed the tender, I watched the voltage drop continuously. Figured it was the battery, so I went a bought a new one at HD (holy cow, $165!!). On the way home I realized I should have tested the VR BEFORE buying the battery. So when I got home, I did check the VR. I did that by disconnecting the stator lead, removing the VR from the frame and check for any voltage from each pin to ground. Both pins show full battery voltage to ground.

So I took the battery back and exchanged it for a new VR. Installed that and then checked for any voltage drop from each pin to ground. SAME THING!! Battery voltage to ground from both pins.

What does that mean? Is this new VR bad, or is the testing described below in item #2 not applicable for these VRs?

Testing The Charging System - Harley Davidson Community

Any insight here would be especially helpful since we have been recommending that folks follow these procedures to test their electrical charging systems. If it is not correct for a certain group of VRs, we need to correct this.

Thanks,

TQ
TQ, doesnt the regulator need to be grounded even for testing?
 
TQ, I would approach the problem by getting the bike to crank & start first. The regulator and/or stator are not really necessary to get the bike to crank and start.

Once the bike can crank & start, then if any problems (charging) remain, we can nail those down one at a time.

So what I would do is install a known good charged battery and attempt to start the bike. See what happens.

Maybe remove the battery, charge it up overnight and load test it to 150 amps for 15 seconds and see what the voltage across the terminals is while the battery is still under the 150 amp load. It should remain above 9.8 volts @150 amps. (If the battery passes that load test, the next move would be to hot wire the start relay)

Would you be able to upload a couple of pages showing the starter, start relay, fuses, ignition switch, & TSM.
 
TQ, doesnt the regulator need to be grounded even for testing?

Jack,

There are two wires on this model. One goes to the "silver" terminal on the breaker, and the other is a ground (large gauge!).

TQ

TQ, I would approach the problem by getting the bike to crank & start first. The regulator and/or stator are not really necessary to get the bike to crank and start.

Once the bike can crank & start, then if any problems (charging) remain, we can nail those down one at a time.

So what I would do is install a known good charged battery and attempt to start the bike. See what happens.

Maybe remove the battery, charge it up overnight and load test it to 150 amps for 15 seconds and see what the voltage across the terminals is while the battery is still under the 150 amp load. It should remain above 9.8 volts @150 amps. (If the battery passes that load test, the next move would be to hot wire the start relay)

Would you be able to upload a couple of pages showing the starter, start relay, fuses, ignition switch, & TSM.

Hoop,

No "extra" battery, so I can remove the Odyssey out of the bike and take it over for a load test. If it passes, then can move on to other stuff. If not, I will go back and get that Holy Cow! battery.

I have attached the schematics I think you wanted. If you need something else, let me know and I will scan them too.

Do you know about the VR issue I described above? I was expecting the new VR to show zero (0) volts on each pin to ground. Is that not the way these new VRs work? Could this new VR be bad?

TQ
 

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There is another Self Help Tip on Charging System tests...

http://www.hdtimeline.com/archive/index.php/t-30685.html

Notice what Hoop recommended was after Step 4 (if you can get the bike started and have the fresh battery in. The regulator is a "shunt" regulator, and all you want to do is run long enough to see the 20V, indicating your stator is producing power. Shutdown...(do not want to run bike for more than a couple minutes at most as this high voltage is a stress on the system if left running.
 
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TQ,
From the diagrams you uploaded, it appears your bike has a Total of 4 relays.
1) Key switch relay
2)Start Relay
3)Stop Light Relay
4) System Relay

At the bottom of page B-37 there is a sub-diagram called "Components Located Under Left Side Cover". The sub diagram shows 2 relays sockets. One is listed as the "Stop light relay", but they failed to label the other relay. I believe that is the "System Relay" but not absolutely sure of that. I am looking for the physical location of the "Start Relay".. We need to find the physical location of the "Start Relay".

The picture of the "System Relay" on the bottom of page B-39 seems to indicate (from having a dotted line around it and 2 fuses) that it is mounted somewhere on it's very own board. But at the same time the system really shown has the receptacle letters of K,T,E,S,U which match the letters inside the left side cover Sub diagram.

See if you can locate (proof positive) the location of your start relay. We are going to have to probe the receptacle of the "Start Relay" once you know the battery is good/charged & ready.

I would put the regulator issue on the back burner just until we resolve the Cranking issue. You may actually just want to unplug the regulator for now because it may be draining your battery. That's what I would do. Just remove the regulator from the picture. Get the bike to crank & start. Once you can do that, hook the regulator back up and check out the charging system. You will not damage the stator with the regulator disconnected from the system.
You may have 2 separate problems but I would repair the start/crank one first.


There are several correct ways to troubleshooting a problem such as yours. There is no single right way to do it but I think this way will you there will the least amount of guessing...
Others may also chime in with some great real world experience and know-how....
 
NEWHD74FAN and Hoople,

What does this mean from the link below?

"Switch multi meter to Diode Scale."

Testing The Charging System - Harley Davidson Community

Yesterday before the battery drained too low to do it, the engine did crank, but very weakly with very dim lights on dash and headlight. After a crank or two, it just chattered like solenoil/starters will do with a very low battery (I am thinking the battery option I started with was probably right, but I second guessed myself!). I am thinking I should pull the battery and go have that load tested. If it fails that, the rest of the system is probably alright, and I just need that Holy Cow battery!! Oh well. Have a spare VR now!!

More details:

Just ran out to the garage. Battery has been on the Battery Tender Jr. all night, and the Vdc across the poles was 13.12 or so. Turned on the switches and tried to start. The starter made one feeble attempt to turn the engine over, and then clicking. Voltage across the poles then read 11+ Vdc. Tried reading the voltage while attempting to crank it, and the voltage was 5+ Vdc while pushing the Start button - clicking only from the Starter. So, anyone vote for new battery?

TQ
 
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NEWHD74FAN and Hoople,

What does this mean from the link below?

"Switch multi meter to Diode Scale."

Testing The Charging System - Harley Davidson Community

Yesterday before the battery drained too low to do it, the engine did crank, but very weakly with very dim lights on dash and headlight. After a crank or two, it just chattered like solenoil/starters will do with a very low battery (I am thinking the battery option I started with was probably right, but I second guessed myself!). I am thinking I should pull the battery and go have that load tested. If it fails that, the rest of the system is probably alright, and I just need that Holy Cow battery!! Oh well. Have a spare VR now!!

TQ

T Q a diode is a one way switch to ensure the electrical current flows one way, if open it will drain he battery the same as on a cage altermator
 
There should be a scale on the meter that has a picture of a diode on it. See attachment.
The selected range on this meter has the picture of the diode to the far right.

An ohm meter uses an internal battery to calculate the ohms in a circuit. The diode range is the "High" range that will "turn on" or forward bias a diode.
 

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