HarleyTechTalk

2012 FLTRX w/120, HPI 58mmTB

Battery and cables all tight.  Have not touched the tach or speedo connector in months.  Bike has thrown tach and speedo loss of data codes for years...

Lately though I'm seeing all sorts of codes.  Everything points to the ECM.  I've never touched the big connector other than check it's seated.  I haven't touched any sensor connectors at all since early December.  I've reset the codes multiple times, last time was before Christmas.  Bike runs great most of the time, but sometimes it acts like it's down on power.  Maybe this is why?

After I clear the codes and I see no codes for a while then out of the blue more codes.   NO engine light.  Ever...   Here's what I pulled friday night.

Edit - ADDed the errors to the list of codes.   (Engine never shut down btw - code P2105)

Codes 27 total:
ECM
p0107 h - Map Open/Low EFI
p0113 h - IAT Sensor Voltage Open/High EFI
p0118 h - ET Sensor Voltage open/high EFI
Tach
U1016 H Loss of ICM/ECM Serial Data Instruments

ECM
P0120 h - Throttle position sensor 1 range error
P0123 h - TP Sensor High EFI
P0220 h - Throttle Position sensor 2 range error
P0222 h - Throttle position sensor 2 low/open
P1001 h - System Relay Coil open/low EFI
P1003 h - System relay Contacts Open EFI

Plus these, which are all "limited power/throttle actuator management related.
P1510 h - Throttle actuator control limited performance
P1511 h - Throttle actuator limited power management mode
P2101 h - Throttle actuator control motor circuit range error
P2105 h - Throttle actuator control system forced engine shutdown

Before replacing the ECM,  I would first check for moisture or corrosion in ALL connections.  That is a lot of codes for simply one problem unless as you say, may be ECM.
C

Check all the grounds on the ECM.

Thanks for the responses.   Does anyone know where the grounds from the ECM connect to the chassis?  Sounds like there are multiple.   2012 Roadglide.  I'll look in the SM tonight. 

I've cleaned and applied dielectric grease to all of the connectors at the top of the engine in the past two months.  Last time I had the gauges removed I greased them too.   

Edit - updated the list of codes with details.  After typing out all the codes it sure does seem like this could be a ground problem.

 

Go through every wire that has a lug to ground and give it a good tug.. On suspicious wires I've found a number that look good but were busted inside..

That's the plan at this point.  I will also pull the large connector off the ECM and make sure it's clean/greased. 

I'll report back.  Thanks for the suggestions.

There should be two ground posts located on the frame in front of the battery tray.
One is for sensor grounds and the other for all other grounds.

Thanks jbee.  I've seen those studs hiding below all the crap HD stuffed in there.   

Well that was fun.  I really hate taking the battery out of a new touring bike.  Removed a crap load of stuff and still was barely able to access the ground studs.  Good news is, both lugs on both studs. Solid.  Wish I was able to easily chase the grounds but with the exception of the run to the negative post the others head out of site. 

Pulled the maxi connector off the ECM all looked good, fiddled with the ground lug a bit, but without taking the connector apart I can't remove it and give it a squeeze.  The connector has always been a little off center.  It's not now.  I also ran a tie wrap around the connector and was able to make it very solid.  Helped with the floppy ECM mount too.   

No codes so far.  Need to ride it and see how things go.  I'll have the fairing off fairly soon so when I do I'll also run those grounds.  Also need to get the tank off so I can access the backbone wiring channel and follow the grounds that run through there.

Side note - Blows my mind how much wiring is on this bike... it's ridiculous.  I love my softail and wide glide, I've removed most of the excess wiring.  Easy peasy to chase problems.

Rage,use a sealed beam head light to load power & grounds. Seen many of grounds check fine with a test light or power probe. Only to load the ground with a sealed beam & it barely lights.


86

Pull the ground on the battery post and wire brush it really well. I had a very similar problem a few months ago with all kinds of strange codes. There was corrosion between the tender eyelet and the ground terminal. I brushed both well, used dielectric grease, reset the codes and have had no problems since.

86, when I get the fairing and tank off this weekend (unless by chance the rain stops and the sun comes out). 

One other thing I noticed, and it's probably contributing, both terminal connections were snug.   Which I'd say is potentially not tight enough.   This new battery I put in last year doesn't have nice soft lead terminals. The terminals appear to be stamped steel or other shiny alloy.   When I put the connections back on I cranked the bolts down much tighter than I would normally.  I don't think I tightened them much more than usual, but maybe...  I don't expect any change with regard to the Tach and Speedo codes I've had since the bike was new.  I expect those are most likely unrelated to this latest weirdness.

I had some seriously crazy demons in a corvette years ago that had tight battery connections, but apparently the connection at the fuse block wasn't *TIGHT*, as in ft-lbs tight.  I think it ended up with 20-25ftlbs... Never a single problem after that...

I noticed when I was checking grounds on my Fat Boy that the frame under the ground cable was a painted surface from the factory. Both grounds were painted underneath.
I scraped the paint off them and sanded to metal and re bolted with dielectric grease.
Should be a good solid ground now.

my evo softail is as you describe.  I put a star washer in there and it's never given me any issues.   The Bagger is using a bare stud with the lugs and nut providing the mechanical connection.  At least for the two grounds under the seat.  I still have the neck and fairing ground to check.  Although I only have issues with the tach and speedo.

A little bit of progress. 

This past weekend I checked the neck grounds and connections associated to the speedo/tach wiring.  No obvious issues found.   Prior to last weekend I saw No Codes all week.  No codes showed up while fiddling around on Saturday either.  Started thinking I might have made some headway...

Yesterday riding home from work about 2 miles out engine was acting a little funky, like an overly lean warm up mixture.  Stopped, pulled codes and I had a fresh code (no H). 
Tach
U1016 Loss of ICM/ECM Serial Data Instruments

Cleared it, rode home everything seemed ok, checked again in the garage, code was back.  Cleared it again, whacked the cluster a couple times, checked for codes again and it was back!  Hmmm... Repeated that same activity again, No Codes...

Starting to wonder if this is a problem inside the Tach itself.  This code has been popping up for as long as I've had the bike.  Maybe this is an excuse to buy a new set of gauges, (i've never liked these silver gauges).  But sure would like to know for sure...