Electrical gurus and Rocket masters help greatly needed/appreciated

Rocketeer4life

Built like a rock
Joined
Sep 27, 2020
Messages
147
Location
Pennsylvania
Ride
2005 Rocket 3
So attempting another post on this, with better thought out detail. My 05 standard finally was fixed to perfect, and i thought it 2 be no biggy to open up the MPH speedo to tighten up, as it was loose. DID disconnect battery+ before tinkering. did spray light amount of simple green to clean out misc gunk inside.
But when i tightened both locknuts on bracket. one side snapped...hence i then went to a jb quick weld state o mind n jus slapped it over both brackets locknut..
while drying i do believe or recall. not entirely sure why, but I did swap 2 relays on left side of bike.
so went on to slap speedo housing back together. and reconnected baterry cable+
but shortly after i realized there was a slight hint of smoke rising from somewhere. thinking this was the entire speedometer unit at first. which then yes as it were, there was no response from speedometer tach in any manner. other than simple housing lights-not indicator lights. RPM Tach still performed well!
Along with not being able to use tune ecu after connecting to bikes ECU- could not perform diagnostic checks! and noticed my left rear turn signal had blown. mind you bike still still starts up fine, sounds good as far as i know.
So after many hrs of reading n lookin up what i could. I attempted disconnecting speedo mph tach harness from behind unit.
removed easily to install again to see the needles sweep and lights come on!
from here i could now pull error codes from tune ecu. p1500, p500. and one other for the tach. but cleared these successfully. with still no luck other than needle sweep.
>checking and replacing fuses as needed<
So went on to replace the current speed sensor with a 05 speed sensor i had. and WALLA. speedometer and odemeter readings back to fine n working!> no fuses seem to be blown?
But now i cannot connect to tune ecu properly, and i fear the engine warning light is not working as it should/ along with all other important information! High beam/ direction turn lights/ neutral light all work fine.
And all lights operate on initial startup sweep with the low oil pressure light going out shortly after.
MY desperate problem is there any way to get the warning light or i guess rather the dianostic circuit working properly?
 
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Does the check engine light come on when u turn on ignition?
Does it go out when it is running?
 
yes it comes on along with the other lights. does go out as soon as bike is running. low oil pressure warning light shortly extingushes after also
i think that the system is working proper the problem is that u can not communicate using tuneecu.
u might try another scanner or code reader.
 
on cars often the diagnostic connector is powered with a fuse that goes to connector and cigarette lighter so we see that fuse blowing and scanners wont work until it (the fuse) is replaced.
any way the diagnostic connecter has a positive and a negative that has to be there for scanners/code readers to work.
 
on cars often the diagnostic connector is powered with a fuse that goes to connector and cigarette lighter so we see that fuse blowing and scanners wont work until it (the fuse) is replaced.
any way the diagnostic connecter has a positive and a negative that has to be there for scanners/code readers to work.
hm, well ive checked all fuses n they seem good. suppose its possible i overlooked a bad one?To be known I can connect to the bikes ecm with tune ecu and get your basic readings of cylinder pressure, various voltages of sensors and etc. Theres simply no option to run various tests. But to add, may be good to know?
ever since this all culminated, the brake light does slightly struggle dimly at first,to give a not all there red>both brakes<and did notice my negative battery terminal is actually friggin cracked!! but still holding the cables firm for now
so are u saying theres another fuse within the diagnostic plugs circuit? ive poured over my full circuit diagram n dont recall seeing it? and thanks so much for putting forth your advice and time. Youv helped me wiggle outta a few jams with my baby, and its had me become more n more familiar with the beast:)
 
Not sure what you mean by negative terminal cracked, but that would be a red flag for me
yeah this was found id say when reconnecting the speedo harness plug to its back.
I speak of the batteries negative terminal. I guess it was already begining to fracture, so as i installed both (i have 2 battery grounds) negative cables, tightening down within reason cracked the batteries terminal. but as cables lay they seem to be temporarily stable. But yes is a flag for sure! i jus dont understand how after unplugging the speedometers harness plug to reconnect, worked to apparently have needle sweep and warning lights, to where i could plug into the ecm and read error codes. all speed sensor related. but after clearing codes and installing new speed sensor. bop. the luxury was gone.lol
 
needs to be fully charged and be on charger while doing tuneecu.
i will definetly attempt it! for now maybe rig the negative terminal to a more solid state, temporarily. although gotta say im almost certain its still providing a strong ground.
Do you feel the swapping of relays had any role to play with this also? battery was probably almost certainly not FULLY charged when attempting at fresh startups.
but had in all honesty, plugged into the bike after multiple runs when testing the speedo/odometer after speed sensor swap.
I was overly paranoid and hopeful that multiple attempts of plugging in would give a safety net. So im curious then if able to fully connect to the ecm, with no warning lights present. does this mean the warning light system is active, to not be at risk of running her when she shouldnt be ridden?
 
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