HAVE A 09 NIGHSTER WAS GOING TO RIDE TODAY WENT TO START TURNED KEY AND DISPLAY WINDOW SHOWS bus er can anyone help me out here and give me some guidance on whats going on fuel pump does its thing can hear it and all display icons stay on in display also already checked all fuses they were ok.

 

Com bus error usually means the ecm can't communicate with the other sensors and actuators.

Check all electrical connections for water or corrosion, as a last resort disconnect the ground wire from the battery for 30 seconds or so then reconnect and see if error goes away.

If it does'nt it could mean the ecm is bad, or at least needs to be hooked up to the factory diagnostic tester to see exactly what the problem is.

 

It`s happened to me twice - it`s the relay - 2 bigger square boxes near the fuses - one is system and the other is start - both the same part # - I now carry a spare with me.

 

pulled the relays and put back in and error went away thanks guys for the help ride safe.

 

You should pull all relays and fuses and check for corrosion,clean as necessary and coat all connections with dielectric grease to prevent further issues.

 

Went to ride yesterday same problem again went back later and checked for any codes had a u1301 i beleive it was whats it mean, went back later and worked as suppose to any ideas what s goin on here,

 

Change the bad RELAY - they are under $10.00 - both are the same part #.

 

Shiftharder do you happen to have that part # handy?, after reading this thread I think i will go pick up a couple to throw in my fork bag....would hate to be a couple hundred away from the house and this happen to me.
Harley should know better than to build crap like that.

 

31601-04 for the relay

If the terminals are powder coated or rusty the part # is 72427-00