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Random TPS code

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Old Jul 9, 2021 | 11:37 PM
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Default Random TPS code

Hope this is the correct sub.

2012 FLHR, 75k stage 1, Tmax tuner.
Had a slew of wiring problems from letting shops work on my bike that included among other things twist grip sensor and TPS codes. Replaced throttle body, TPS plug and extended the harness 5 inches, all new wiring from bars to light bucket and new twist grip sensor. Now I get random TPS codes every couple weeks to a month that throw it into limp home mode, clear the code and it disappears for another few weeks. This only occurs at low speed working up through 1st, 2nd, 3rd gear, never on highway at 80mph. I've exercised the spliced TPS harness and plug but cannot reproduce it. Probably not related but I also recently had two codes that indicated a possible voltage surge, my ECM fuse blew, and the 2nd to last time I got the TPS code my HD mutil-function speedo lost half it's functionality and lost 10k off the odometer. Thoughts?
 
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Old Jul 9, 2021 | 11:44 PM
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Sounds like either a broken wire or a chaffed wire that is intermittently shorting. With the motor idling, shake and twist every wire, cable, and connector between the throttle, ECU, and TPS.
 
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Old Jul 10, 2021 | 01:18 AM
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Originally Posted by TriGeezer
Sounds like either a broken wire or a chaffed wire that is intermittently shorting. With the motor idling, shake and twist every wire, cable, and connector between the throttle, ECU, and TPS.

Thanks for the reply but I've done that, pulled back the heat wrap, inspected and exercised the wiring, connectors, and plugs. It sounds electrical to me also but the way the bike vibrates and the number of miles I ride each month I'd think it would occur more often.
 
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Old Jul 10, 2021 | 06:43 AM
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you lost 10k miles out of the memory??? most unusual!!!
i do not think that mileage is stored in E2prom. it sounds like there is an internal issue with the ecu. however, surging electrical could be caused by bad ground on the regulator which could cause electrical spike which electronics do not like. i would also check the ac ripple out of the regulator, dc electronics do not like that either, the battery acts like a giant capacitor and absorbs it to an extent but if high enough, it will cross over the battery into the system.
 
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Old Jul 10, 2021 | 06:51 AM
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What is the full list of codes you have seen?
 
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Old Jul 10, 2021 | 12:22 PM
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Originally Posted by bustert
you lost 10k miles out of the memory??? most unusual!!!
i do not think that mileage is stored in E2prom. it sounds like there is an internal issue with the ecu. however, surging electrical could be caused by bad ground on the regulator which could cause electrical spike which electronics do not like. i would also check the ac ripple out of the regulator, dc electronics do not like that either, the battery acts like a giant capacitor and absorbs it to an extent but if high enough, it will cross over the battery into the system.

Yeah it was crazy, lost 10k, couldn't cycle the odometer functions or read codes, and I think lost gear indication. I'd replaced the HD regulator a couple months ago and just replaced the original 75k stator with a Cycle Electric last week thinking along similar lines as you are. The stock is ECU has been replaced with a Tmax, I sent data to them from the tuner and they came up empty. Maybe replacing the Stator will resolve the issue?
 
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Old Aug 9, 2021 | 02:22 PM
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Originally Posted by TheCoffee
Hope this is the correct sub.

2012 FLHR, 75k stage 1, Tmax tuner.
Had a slew of wiring problems from letting shops work on my bike that included among other things twist grip sensor and TPS codes. Replaced throttle body, TPS plug and extended the harness 5 inches, all new wiring from bars to light bucket and new twist grip sensor. Now I get random TPS codes every couple weeks to a month that throw it into limp home mode, clear the code and it disappears for another few weeks. This only occurs at low speed working up through 1st, 2nd, 3rd gear, never on highway at 80mph. I've exercised the spliced TPS harness and plug but cannot reproduce it. Probably not related but I also recently had two codes that indicated a possible voltage surge, my ECM fuse blew, and the 2nd to last time I got the TPS code my HD mutil-function speedo lost half it's functionality and lost 10k off the odometer. Thoughts?

RESOLVED (probably lol): I've put over 500 miles on the new stator and haven't had the TPS code since, I did get another battery over-voltage code for probably the third time, not sure what's going on there. My guess is the original stator with 75k on it may have been causing my random codes and the one blown ECM fuse. Maybe. Thanks for all who responded.
 
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