I think I have a bad BCM
I think I have a bad BCM
I posted before about my 2013 Heritage not starting. O found that the BCM was only sending about 5 volts to the starter. I'm also experiencing issues with a brand new horn sounding anemic and if I start the bike with bright lights on then all the lights go off and won't come on until I shut the bike off and restart it with lights on low beam. To me, all this points to a bad BCM. Wondering if anyone else has experienced these issues and found it to be the BCM? Also wondering if anyone has replaced a BCM on their own and what kind of tool you used to do it? It is my understanding that you have to connect a diagnostic tool to tell the ECM to recognize the new BCM.
Grand HDF Member
Joined: Nov 2012
Posts: 4,997
Likes: 2,083
From: Newport,TN area
There IS a Body Control Module - basically it's a solid-state suite of circuit breakers...
https://partsfinder.onlinemicrofiche...UIT%20BREAKERS
See #15, HD part numbers
# 41000348F BODY CONTROL MODULE (BCM), BASE LEVEL*
# 41000349F BODY CONTROL MODULE (BCM), 434 MHZ, SECURITY
hth,
T.
https://partsfinder.onlinemicrofiche...UIT%20BREAKERS
See #15, HD part numbers
# 41000348F BODY CONTROL MODULE (BCM), BASE LEVEL*
# 41000349F BODY CONTROL MODULE (BCM), 434 MHZ, SECURITY
hth,
T.
Grand HDF Member
Joined: Nov 2012
Posts: 4,997
Likes: 2,083
From: Newport,TN area
So back in 2013, I rode my FLS Slim to the dealer, then removed the rear struts/fender and splashguard in the parking lot.
I replaced the 'basic' BCM with the 'Security' BCM and then replaced the removed parts above.
I let the Service Advisor know I needed my BCM and key fobs programmed. I think they charged me like $50 to do that.
I then rode back to my house.
All that to say - yes, I do think you need to have a dealer 'program' or 'update' the ECM when a new BCM is installed.
good luck,
T.
I replaced the 'basic' BCM with the 'Security' BCM and then replaced the removed parts above.
I let the Service Advisor know I needed my BCM and key fobs programmed. I think they charged me like $50 to do that.
I then rode back to my house.
All that to say - yes, I do think you need to have a dealer 'program' or 'update' the ECM when a new BCM is installed.
good luck,
T.
Seasoned HDF Member
Joined: Sep 2008
Posts: 14,160
Likes: 11,249
From: San Diego, CA
I posted before about my 2013 Heritage not starting. O found that the BCM was only sending about 5 volts to the starter. I'm also experiencing issues with a brand new horn sounding anemic and if I start the bike with bright lights on then all the lights go off and won't come on until I shut the bike off and restart it with lights on low beam. To me, all this points to a bad BCM. Wondering if anyone else has experienced these issues and found it to be the BCM? Also wondering if anyone has replaced a BCM on their own and what kind of tool you used to do it? It is my understanding that you have to connect a diagnostic tool to tell the ECM to recognize the new BCM.
If you change the BCM, it will need to be "configured" via the dealers Digital Tech II. Several of the aftermarket diagnostic tools can also do it, like my Twin Scan IV or the TechnoResearch Centurion.
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Grand HDF Member
Joined: Jul 2007
Posts: 3,740
Likes: 8,537
From: Bates County MO
I'd suspect the battery/connections. Time to break out the multi meter, and measure static battery voltage 4x, 1) key off ( looking for >12.6V) , 2) key on with low beam on( 12.4-12.5) , 3) key on with hi beam on(12.2-12.4) and 4) key on, lo beam on, attempt to start- has to be above 11.8 under load. The starter system will not activate if voltage is too low. System is designed to turn the headlight off while starter is engaged, so all the current is going to the starter. The BCM will check battery voltage while cranking, and current draw, and if it's parameters are exceeded, turn itself off.
Compare reading #4 to the voltage at the starter post while cranking- they should be very close- with in a tenth or two, if all connections are healthy.
Compare reading #4 to the voltage at the starter post while cranking- they should be very close- with in a tenth or two, if all connections are healthy.
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[
I bypassed the bcm by installing a momentary push button switch which supplies 12 volts directly to the solenoid. The bike starts and runs fine this way but, as I said, I'm having other electrical issues and the common denominator is the BCM. The horn, starter switch, lights are all tied to the BCM plus I used an ohm meter on the wire from the BCM to the solenoid and got very low resistance and checked the voltage right at the bcm and it was low there. That's why I'm thinking this is a BCM issue and not a wiring issue unless I'm missing something?
QUOTE=rigidthumper;20194341]I'd suspect the battery/connections. Time to break out the multi meter, and measure static battery voltage 4x, 1) key off ( looking for >12.6V) , 2) key on with low beam on( 12.4-12.5) , 3) key on with hi beam on(12.2-12.4) and 4) key on, lo beam on, attempt to start- has to be above 11.8 under load. The starter system will not activate if voltage is too low. System is designed to turn the headlight off while starter is engaged, so all the current is going to the starter. The BCM will check battery voltage while cranking, and current draw, and if it's parameters are exceeded, turn itself off.
Compare reading #4 to the voltage at the starter post while cranking- they should be very close- with in a tenth or two, if all connections are healthy.[/QUOTE]
I bypassed the bcm by installing a momentary push button switch which supplies 12 volts directly to the solenoid. The bike starts and runs fine this way but, as I said, I'm having other electrical issues and the common denominator is the BCM. The horn, starter switch, lights are all tied to the BCM plus I used an ohm meter on the wire from the BCM to the solenoid and got very low resistance and checked the voltage right at the bcm and it was low there. That's why I'm thinking this is a BCM issue and not a wiring issue unless I'm missing something?
QUOTE=rigidthumper;20194341]I'd suspect the battery/connections. Time to break out the multi meter, and measure static battery voltage 4x, 1) key off ( looking for >12.6V) , 2) key on with low beam on( 12.4-12.5) , 3) key on with hi beam on(12.2-12.4) and 4) key on, lo beam on, attempt to start- has to be above 11.8 under load. The starter system will not activate if voltage is too low. System is designed to turn the headlight off while starter is engaged, so all the current is going to the starter. The BCM will check battery voltage while cranking, and current draw, and if it's parameters are exceeded, turn itself off.
Compare reading #4 to the voltage at the starter post while cranking- they should be very close- with in a tenth or two, if all connections are healthy.[/QUOTE]