Before affected 2012 owners replace their regulator, check the condition of the shield covering the DC outlet wire...it's the two-wire bundle that leaves the right side of the regulator and passes under the right engine motor mount. It goes to the 40 amp fuse (B+) and chassis ground (B-).

On my new '12 Road King that wire was jammed between the frame and the right motormount bolt head that extends below the front of the engine. When running, that shaking bolt had chafed through the external rubber/fiberglass wiring shield, and was on the way through the wires inside in only a few hundred miles. The chafe area is on top of the bundle, and hard to see unless it's pulled out from under the frame.

If the bolt head eventually wears through the B+ wire insulation, it can cause intermittent high current demand on the alternator system and may cause it to fail. If sustained, it should blow the 40A fuse between the wire and battery. I didn't have a problem yet.

For a fix I put some 3/4" heatshrink tubing over the worn area and cable tied the wire bundle away from the bolt.

Gary

 

You may have discovered the cause for the multiple regulator failures.

 

Thanks for the tip Gary, will definitely be looking for that condition on mine!

 

Well, there may still be defective regulators despite the potential for wire chafing. I replaced my regulator with an older unit just in case. My build month, 11/11, was in the reported range of problematic bikes. No need for downtime from a lack of parts in our short Alaskan riding season. That's when I discovered the pinch and chafe on the DC output wires.

Just follow the two wire covered bundle back from the regulator's right side under the engine. If it's pinched it's obvious, so's the covering fraying. There were white fiber strands from the cover all over the wires nearby.

I can see where it'd soon be a problem once it chewed through the wire's covering. Have a look and tie the wires away from the offending engine bolt head.

 

Gary, when you replaced your regulator did you have to remove the oil cooler? My service manual doesn't mention it but the cooler sure looks like it's in the way. Also, the build month (12/11 on mine)...is that the date on the sticker on the tourpak lid, and do you recall the reported range of problematic bikes? Thanks

 

I removed the two bolts that hold the oil cooler to the frame, and then carefully pulled it up some (hoses attached) and tied it out of the way. That allows enough room to unfasten the regulator nuts with a deep socket and remove the unit.

Note the two plastic U-clips that have to be swung away 90 deg to remove wiring plugs. After cleaning the contacts with alcohol and a swab, I sparingly put some dielectric grease on the plugs and metal contacts, and made sure any split female contacts were closed so there'd be a good fit when assembled. There's not much slack in the two-wire DC bundle. Make sure it's not pulled under the engine mount bolt when done (look under the motor), or it'll fray as I mentioned above. Tie it off with the rest of the wires under there.

The month/year build date for the bike is on a decal stuck to the front frame tubes. Look for it. Anecdotal Internet info suggests 10/11-2/12 as the problem build dates (?) when some defective regs were installed (?). My original factory regulator had a build date (week of year?) of 4511. The new unit I installed was 0610. It's stamped in white on the rear, along with P/N 74505-09. The original was still working ok, but I didn't want to risk a mid-trip failure for a $200 replacement.

If the regulators are indeed defective (bad batch for example), then H-D needs to offer-up a build date S/N range for the defective regulators. It can easily be seen with a mirror held in back of the installed unit. Also check the DC wires for chafing as noted.

Gary

 

Thanks man!

 

Thanks Gary for the great information. Planning a pretty long trip in a couple weeks and still weighing my options. Hate to admit it but I've upgraded my towing coverage to include up to $1K worth of collateral expenses related to the failure of a warrantied part. I say hate to admit it because even though it was only $10, you shouldn't have to do this on a brand new bike. I suppose if I can find one of those finned, chrome VR's for $160 I'd just take it along but local dealers and J&P are out of stock.

 

I have a 2012 Street Glide and called HD sevice and asked them if the voltage regulators are bad.
The guy at H-D service, nice guy too said yes and that if you have one manufactured between 3-9-11 and 5-1-11 Harley will replace them before they go. He said they sure the time periods got the bad ones. Also the number to refer this item is #1261049.
The V/R on mine reads like this 4311. My dealer is ordering me a new one.

 

Thanks for the heads up. I'll be inspecting mine.