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how do you fix bcm code b2121,

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Old Jul 15, 2017 | 04:37 AM
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Default how do you fix bcm code b2121,
harley davidson FXDWG 2015 , WILL NOT START ,CAN JUMP SOLENOID TO BATTERY IT STARTS , ERROR CODE B2121 , STARTER OUTPUT OPEN ? HOW DO YOU FIX
 
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Old Jul 15, 2017 | 05:51 AM
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Originally Posted by widey
harley davidson FXDWG 2015 , WILL NOT START ,CAN JUMP SOLENOID TO BATTERY IT STARTS , ERROR CODE B2121 , STARTER OUTPUT OPEN ? HOW DO YOU FIX
Starter relay?
 
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Old Jun 15, 2018 | 11:28 AM
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Originally Posted by widey
harley davidson FXDWG 2015 , WILL NOT START ,CAN JUMP SOLENOID TO BATTERY IT STARTS , ERROR CODE B2121 , STARTER OUTPUT OPEN ? HOW DO YOU FIX
2013 FXSB. I have the exact same problem. Anyone?
 
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Old Jun 16, 2018 | 07:23 PM
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It is seeing the switch so I'd look at the starter relay. Is your neutral light coming on in neutral?
 
Last edited by Jay Guild; Jun 16, 2018 at 07:26 PM.
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Old Jun 17, 2018 | 04:47 AM
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Originally Posted by Jay Guild
It is seeing the switch so I'd look at the starter relay. Is your neutral light coming on in neutral?
Neutral light is on. Have checked clutch in, kickstand and other possible combinations, but no go. Fuel pump runs and all lights are as normal when I turn the ignition and Run switch on, but when pushing the start switch, the headlight goes off then nothing. Checked and found a slightly pinched cable in the RHCM. Fixed this, cleared all codes and tried again. Still nothing.
Starts if I jump it from the starter relay plug to the battery. Now there are two DTC's left on the BCM diag. B2121 (Starter Output Open/BCM Malfunction?) and B2122 (Starter Output Shorted High?).
 
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Old Jun 17, 2018 | 11:03 AM
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Pull the relay and do continuity tests on the posts. The only other thing it sounds like it could be is is a pinched wire from the start switch.
 
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Old Jun 17, 2018 | 01:27 PM
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Fuse ? side stand switch.
 
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Old Oct 7, 2018 | 06:03 AM
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Where is located the starter relay ? and the fuses on a FXDB 2014 ?
 
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Old Mar 16, 2019 | 05:15 AM
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hello dear,

how was this issue solved? I am facing the same problem on my FLD 103 2014



Originally Posted by TGR2016
Neutral light is on. Have checked clutch in, kickstand and other possible combinations, but no go. Fuel pump runs and all lights are as normal when I turn the ignition and Run switch on, but when pushing the start switch, the headlight goes off then nothing. Checked and found a slightly pinched cable in the RHCM. Fixed this, cleared all codes and tried again. Still nothing.
Starts if I jump it from the starter relay plug to the battery. Now there are two DTC's left on the BCM diag. B2121 (Starter Output Open/BCM Malfunction?) and B2122 (Starter Output Shorted High?).
 
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Old Mar 16, 2019 | 10:40 PM
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I believe the starter relay and system relays are the same, swap them out and check to see it starts.
 
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