HFSM refusing to disarm; urban spot (one solution)

[SwissXL]

Hi there, just a brief contribution to the issue of proximity FOB not being recognized.

Very recently my son's 2011 Nightster's HFSM (the keyless security system) refused twice to disarm in the same spot in the city. Moving the bike away resolved the issue.

Without going into the science behind this technology, the HFSM works with a proximity FOB connected by radio-frequency (RF) to the HFSM RF receiver. The receiver can be saturated by an interference like any RF device, potentially rendering the proximity FOB temporarily ineffective. Moving the bike away from the "bermuda spot" reduces the interference and resolves the issue. Anyone that has been in signal troops or an engineer might chime in and elaborate.

This suggests that in case your HFSM acts up inopportunely in an urban area, before disassembling things, make sure the problem is not caused by a localized interference by simply moving the bike away.

"Away" can be relative. In our case it was about 20m. Possibly an underground high-voltage substation (there is no visible industrial equipment around). How did we find out the 20m? simply because the alarm stopped sounding and the "red key" light turned off.

If you are in the middle of nowhere, RF interference might not be your problem.

The bike is in perfect operational order and the HFSM has never been uncooperative before. Replacing the batteries of both FOBs had no effect. The issue can be replicated. So the external interference is confirmed.

'hope this helps someone

[a-sad-anorak]

My brother and a friend rode from the UK down into Spain for a rally. They stopped for petrol at a garage only to find that my brother couldn't start his bike. His friend on the other side of the pumps started his bike with no problems. Called out a mechanic who moved the bike to the other side of the forecourt and the bike started. They said it was due to the radio interference from the police station opposite the garage. Apparently the problem is not unusual in Spain.

[SwissXL]

Originally Posted by a-sad-anorak

My brother and a friend rode from the UK down into Spain for a rally. They stopped for petrol at a garage only to find that my brother couldn't start his bike. His friend on the other side of the pumps started his bike with no problems. Called out a mechanic who moved the bike to the other side of the forecourt and the bike started. They said it was due to the radio interference from the police station opposite the garage. Apparently the problem is not unusual in Spain.

maybe we need tin foil hats for our HDs....

[IXL2Relax]

SwissXL - Thanks for posting.

I've added a paragraph to the Sportsterpedia on this issue (with reference to this thread):
http://sportsterpedia.com/doku.php/t...tssm_and_siren

NOTE: All devices that use Radio Frequency (RF) signals to function have susceptibility to signal overload from unintended sources of RF signals from other electronic or electrical devices in close proximity to them. The security functions may not work or have difficulty responding to the FOB in locations with high RF signals from other sources. Moving the bike to a different location may allow proper functioning, but distance may vary from 10-100 feet depending on the source of interference.

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[SwissXL]

Originally Posted by IXL2Relax

SwissXL - Thanks for posting.

I've added a paragraph to the Sportsterpedia on this issue (with reference to this thread):
http://sportsterpedia.com/doku.php/t...tssm_and_siren

Explore The Sportsterpedia - The Best Kept Secret on the XLForum![/URL][/SIZE][/B]

Thanks @IXL2Relax

[SLW210]

My FXLR Softail can also be deactivated with a PIN code.

Lots of info out there on the RF interference on FOBs, check the Tesla forums and other car forums. Seems most interference comes from errant WiFi or other wireless devices, some claim having too close to their cell phone kills it.

I read up on that when the FXLR started having problems, but that turned out to be the regulator.