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Wire harness issue ‘12 wide glide

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Old Aug 16, 2018 | 03:57 PM
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Default Wire harness issue ‘12 wide glide

Brought my 2012 wide glide to Hannums in Rahway NJ 2 months ago for diagnostics and repair. The speedo started to read 00 for the MPH after about 30 minutes of riding. The idle was all over the place sometimes causing the bike to shut off. When I opened the throttle all the way the bike would “chug” and sometimes die. After 2 months of trying to figure out what was wrong the tech at Harley told me I need to replace my wire harness. About a $2k job ($1200 for the part plus labor). I’m going to just buy the harness used and do the job myself with the help of a mechanic friend. I looked online for the wire harness and I see some aftermarket things and kits, I’m not sure if those will work. I guess I don’t really have a question. More just looking for guidance and or pointed in the direction to a used wire harness
thanks in advance
 
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Old Aug 16, 2018 | 06:44 PM
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What did he find wrong with the wiring that you need to replace the whole harness? What Diagnostic trouble codes did the bike have?
 
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Old Aug 16, 2018 | 07:09 PM
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I have the same question as Vernal? Before going out and replacing an entire wiring harness take a look at these threads as I believe they reflect what you are experienceing?

https://www.hdforums.com/forum/touri...nsor-fail.html

https://www.*****************/forums...o-problem.html
 
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Old Aug 16, 2018 | 08:05 PM
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He said that he couldnt figure out what exactly was wrong with it. He said a connection is touching ground somewhere. First he thought it was my aftermarket speedo screwing witht he ecm. Sent out for a new ecm (or to get mine flashed i cant remember) and that wasn’t the issue
 
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Old Aug 16, 2018 | 08:22 PM
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Oh yea codes. I was getting map sensor and throttle position sensor code and replaced them, that wasn’t the issue. Also some 5 volt code
 
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Old Aug 16, 2018 | 10:35 PM
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Have you confirmed your aftermarket speedometer is good? By chance do you have the stock speedometer and have you tried reinstalling it to see if the codes clear?
 
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Old Aug 16, 2018 | 10:42 PM
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That's what they thought. I brought my original speedo to them and they said it was still acting up.
 
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Old Aug 16, 2018 | 10:43 PM
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Also the aftermarket speedo worked for months without issue
 
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Old Aug 16, 2018 | 10:58 PM
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I don't have any Dyna Manuals but looking in the 2015 Touring Electrical Diagnostic Manual the P0641 5 volt reference out of range comes first on the Priority list. That means this DTC should be resolved first. Looking at a Schematic from:

https://serviceinfo.harley-davidson....d-d44bf7213f3d

Basically you check voltage on the 5 volt sensor power pin 9 R/W on ECM connector 78b-2 with the ignition on and the connector connected to the ECM. It should be 4-6V. If it is, start wiggling wires and connectors and see if it drops.

If it's less than 4v turn ign off and disconnect VSS, JSS,Map and TPS one at a time, turn Ign back on and see f the voltage comes back to 4-6V . You may only need to check VSS since you replace the other two. I don't think you have a JSS, Jiffy Stand Sensor.

If it's higher than 6v find the short to voltage.

Disconnect the ECM and check continuity from pin 9 78B-2 to ground, it should be open. If you have continuity to grd find the short.

Check continuity between pin 9 R/W and pin 7 BK/W 78B-2 repair short if continuity is present.

If it all checks out replace ECM. I'll add some pictures.



 

Last edited by Vernal; Aug 16, 2018 at 11:01 PM.
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Old Aug 16, 2018 | 11:01 PM
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I really appreciate all of that info and I'll pass it along to my mechanic friend that's going to lend me a hand as it is way over my head
 
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