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Stepper motor repaired. Triangle of death gone bye bye.

As a matter of principal, I will not offer assistance or advice to anyone here who messes with the welded up/painted shut, “sacred screw” on the throttle stop plate.

If someone wants to be supremely stupid, even after I have given complete information as to precisely why you don’t mess with it, then I don’t want any part of their madness.

I wish mine was welded so it would at least deter anyone from playing with it. I have always been a "by the book" guy. If the manual says don't touch then I don't touch.

I managed to get the stepper off before leaving this morning (about 4AM) and to my surprise it checked out exactly as yours did. No short to the case and no short between windings. Pins 1 and 4 had continuity with 50 ohms. Pins 2 and 3 had continuity with the same 50 ohms. Additionally the stepper was clean. I then checked the connector on the loom and found pins 2 and 3 were short to ground. Correct me if I am wrong but that can't be right. There must be a short in the loom. I started pulling plastics from around the tank, and then had to head south out of town. I didn't notice anything suspicious in the portion of the loom that I could see but here's the thing;

1) The bike has no real miles on it. < 10,000 miles so abrasion from normal wear on the loom seems unlikely.

2) The 2 shops that worked on the bike were horrible and had no idea of what they were doing. In addition to the taped up spark plug cap, I found missing washers, stripped/missing screws, hoses routed improperly and burning where rubbing on the exhaust etc.

3) The last guy pulled the right fairing away from the tank leaving the front of the fairing attached and squeezed in between the tank and the fairing to replace the oil pressure switch.

4) I know from experience in my profession that when a problem arises you consider any recent changes in routine to point you in the right direction. i.e. whenever we had a sudden drop in pressure in the City water main system the first place we would look is where a contractor was excavating. 70% of the time we would find a contractor scratching his head standing next to a hole full of water after digging into our water main.

Considering these points I have to think it is very likely this short was induced by something the last shop did. That said unless you have a better suggestion I'll finish pulling the tank this weekend and start looking in the same area where he was working.
 
I then checked the connector on the loom and found pins 2 and 3 were short to ground. Correct me if I am wrong but that can't be right. There must be a short in the loom.

No no no! We are interested in pins 9, 17, 18, 19 on Connector (E) in the diagram. They are the 4 wires running to the steeper motor remember. Look for a short to ground in those wires. There should be nothing given that the plug is disconnected to the steeper motor now.
 
Pins 2 and 3 could be connected to earth back at the ECU and control voltage goes down 1 and 4, as Scott says check for a short/earth in 9, 17, 18 and 19, isolate the cable at each end.
 
Thanks Kevin,
I disconnected the ecu and the stepper. With the wires isolated I found pin 9 (pink wire) is shorted to ground as well as pin 19 (purple wire). 9 and 19 also have continuity to pins 2 and 3 at the stepper connector.
 
No no no! We are interested in pins 9, 17, 18, 19 on Connector (E) in the diagram. They are the 4 wires running to the steeper motor remember. Look for a short to ground in those wires. There should be nothing given that the plug is disconnected to the steeper motor now.
Yes Scott,

My bad, I wasn't clear. I had both ends disconnected and 9 and 19 on connector E are short as well as the pins 2 and 3 that are the other end of the same wires...
 
Hey Scott,
Hope all is well..

The fairings and the tank are off the bike (not fun but absolutely necessary). I give it an F bomb rating of 7 on a scale of 1 to 10. L.O.L.

That said I was able to follow the loom from the ecu to the stepper connector and found no abrasions, cuts or anything suspicious. I am starting to think the short is in the ecu connector. With all the previous warning light issues I have had lately the shops and I have pulled that connector off numerous times and without pulling the fairings. That results in very tight spaces and a bit of tugging on the connector. I know these connectors can be disassembled to check wiring but I'm not sure how to pull it apart without damaging it.
 
KayJay,

Did You actually look down inside the two sides of the ECU itself? Those pins are tiny and if any are missing or bent it would be easy to miss without magnification. Again, in the end, that's what caused my Stepper motor error on dashboard.
 
KayJay,

Did You actually look down inside the two sides of the ECU itself? Those pins are tiny and if any are missing or bent it would be easy to miss without magnification. Again, in the end, that's what caused my Stepper motor error on dashboard.

EXCELLENT POINT!

I didn’t think to physically inspect the pins! Out of sight out of mind.

Definitely look for a bent or broken one!
 
EXCELLENT POINT!

I didn’t think to physically inspect the pins! Out of sight out of mind.

Definitely look for a bent or broken one!
The pins on the ecu are perfect. I'm wondering about where the wires from the loom enter the ecu connector.
 
EXCELLENT POINT!

I didn’t think to physically inspect the pins! Out of sight out of mind.

Definitely look for a bent or broken one!
The pins on the ecu are perfect. I'm wondering about where the wires from the loom enter the ecu connector.
 
I'll take another close look with a mirror tomorrow. I wish I could see inside the back side of that ecu connector. I really want to rule out a couple of wires being pulled away from the connector receptacle... Then again i don't know where there is any ground potential inside the connector for the wires to short to unless a ground wire is in the bundle and pulled out as well.

Thanks Guys,
Maybe I'll have better luck tomorrow :wondering:
 
Holy S**t!

The good news is the short is gone! The bad news is I don't no why! I didn't do anything other than pull the fairings and tank and then fool around with the ecu connector to try and find out how to pull it apart. There is essentially no area under the tank where the loom is close to anything I pulled off , tank included. I found no chafing, or any other damage to the loom. Like I said, I did play around with the ecu connector but I have been wiggling the ecu connector around while checking pins 2 and 3 at the stepper but could not get the short to come back. Pins 9 and 19 at the ecu are no longer shorted either. To remove the fairings I disconnected the front turn signals, headlights and fog lights but I can't see how that could have anything to do with the 4 wires to the stepper. In my 63 years I have been an apprentice heavy equipment mechanic, earned a commercial pilot license, repaired TV's in the 70's and worked for the water utilities department in a local municipality for 32 years, 20 of those were as a field Operations Superintendent in charge of over 600 miles of pipe and 150 pump stations. I have seen a lot of strange things mechanically speaking but this has me completely baffled!!! WHISKY TANGO FOXTROT!!!
 
Holy S**t!

The good news is the short is gone! The bad news is I don't no why! I didn't do anything other than pull the fairings and tank and then fool around with the ecu connector to try and find out how to pull it apart. There is essentially no area under the tank where the loom is close to anything I pulled off , tank included. I found no chafing, or any other damage to the loom. Like I said, I did play around with the ecu connector but I have been wiggling the ecu connector around while checking pins 2 and 3 at the stepper but could not get the short to come back. Pins 9 and 19 at the ecu are no longer shorted either. To remove the fairings I disconnected the front turn signals, headlights and fog lights but I can't see how that could have anything to do with the 4 wires to the stepper. In my 63 years I have been an apprentice heavy equipment mechanic, earned a commercial pilot license, repaired TV's in the 70's and worked for the water utilities department in a local municipality for 32 years, 20 of those were as a field Operations Superintendent in charge of over 600 miles of pipe and 150 pump stations. I have seen a lot of strange things mechanically speaking but this has me completely baffled!!! WHISKY TANGO FOXTROT!!!
Fantastic! Well done! Get it back together and do some riding. I will contact you when I have time to ride the O loop. This time of year is best for touring due to low temps outside go enjoy.
 
Holy S**t!

The good news is the short is gone! The bad news is I don't no why! I didn't do anything other than pull the fairings and tank and then fool around with the ecu connector to try and find out how to pull it apart. There is essentially no area under the tank where the loom is close to anything I pulled off , tank included. I found no chafing, or any other damage to the loom. Like I said, I did play around with the ecu connector but I have been wiggling the ecu connector around while checking pins 2 and 3 at the stepper but could not get the short to come back. Pins 9 and 19 at the ecu are no longer shorted either. To remove the fairings I disconnected the front turn signals, headlights and fog lights but I can't see how that could have anything to do with the 4 wires to the stepper. In my 63 years I have been an apprentice heavy equipment mechanic, earned a commercial pilot license, repaired TV's in the 70's and worked for the water utilities department in a local municipality for 32 years, 20 of those were as a field Operations Superintendent in charge of over 600 miles of pipe and 150 pump stations. I have seen a lot of strange things mechanically speaking but this has me completely baffled!!! WHISKY TANGO FOXTROT!!!

Believe me, it is often times simply a matter of unseating and reseating connectors and these errors can appear and disappear. Some electrical contact cleaner does miracles sometimes. Ground signal is also controlled electronically through the ECU and reseating the cables just might have done the trick?

I’ve also see all manner of hell from dielectric grease being used by do-do mechanics who do not know that dielectric grease is an insulator from conductivity. Not that this is your problem here but there are all kinds of reasons really.

I’m thrilled that the short is gone!

Reconnect the ECU and steeper and immediately try and reset the error with the dash diagnostics!

If that works then as my friend, Kiwi says, “Then Bob’s Your Uncle!”
 
So there was no "smoking gun" , leaves me feeling a bit anxious . Too many years as a mechanic I guess . Peter
Moto-Uno,

I am as well. Too much work to have the problem re-appear once things are back together. That said, while working for the City I had 4 electricians working with my team. I remember one of them telling me he was cautious about using too much contact cleaner as he had had shorting issues immediately after using it on our logic and command software. Our Chief electrician backed that up when I asked him about it.
I used de-oxit on the ecu pins and into the connector the last time I had the connector disassembled from the ecu. This was immediately before getting the stepper motor short. Remembering what the electricians told me years ago I used some compressed air to blow out any excess contact cleaner before re assembling the ecu connector.

So, here is the question:

Looking for opinions here, Does anyone think it is possible that there was enough de-oxit in the connector to short the wire connections, and after sitting disconnected for several days, the excess contact cleaner drained/dried out???

Admittedly, this is grasping at straws but better to take the time now to rule out any re-occurrence while the bike is apart.

MOST IMPORTANTLY, THANK YOU ALL FOR THE HOURS OF ADVICE, REASSURANCE, AND SUPPORT. ESPECIALLY SCOTT FOR SHARING HIS YEARS OF EXPERIENCE. As I put everything back together I may have a question or two, but for now with the help of the forum, I have achieved my goal in by-passing the "do do" mechanics.

Next step is to make another donation to the forum!
 
Deoxit D5 is a strange brew. I have it in my shop.

There are times I use and like it and there are other times I don’t.

It has that lubricant residue that sometimes make me wonder. If I have any doubts, I switch to CRC Contact cleaner.
 
Fantastic! Well done! Get it back together and do some riding. I will contact you when I have time to ride the O loop. This time of year is best for touring due to low temps outside go enjoy.

Yes indeed!

I will be tied up this coming week so putting the bike back together may have to wait until the holiday weekend. Also waiting for a few parts, 4 and 5mm clips as well as a new passenger seat release cable. On occasion a couple of friends from Broward County call me to set up the Lake O loop ride as well. May be nice to get a group together for the ride or we may take a ride to your neck of the woods. I really like visiting Ft. Myers, especially the area around the pier....
 
Deoxit D5 is a strange brew. I have it in my shop.

There are times I use and like it and there are other times I don’t.

It has that lubricant residue that sometimes make me wonder. If I have any doubts, I switch to CRC Contact cleaner.
Exactly what I was thinking. I have the crc stuff as well. You think a shot of that to clean out any lube residue is in order??
 
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