How To Fix TBW Issues After Internal Wiring

[Donk]

Ok so I personaly have experienced many hours of frustration and anger dealing with the TBW and wiring my bars internally. I have heard of several issues people have had and have experienced a few on my own. I am going to list a few common issues and how to fix them, and then I have also included a write up on how to hard wire the TBW and elminate the connectors.

Cruise not working= either one of two things. 1) Your brake switch is broken from not shimming the brake lever out. The brake switch is a little plunger between the brake lever and the master cylinder. Squeeze your brake lever and you can see it. The bike thinks the brakes are on, and therfore the cruise will not engauge. 2) TBW green connector inside the bar has a weak connection. I had this issue during the pulling of my wires though the bars. I pulled the green coonnector out just enough to make it lose connection for cruise to work properly. Either tape the green connector very tight or shrink wrap it. The other option is to hard wire... write up is at the bottom of this thread.

Brake lights stay on= The brake switch is broken.. refer to the above explanation.

Bike feels slugish/no power band/will not rev very high in the RPM range= TBW has loose connection or poor connection. Either tape the green connector very tight or shrink wrap it. Neither is guaranteed to keep it connected but it might work if there is enough room inside your bars. Or you can hard wire the TBW... keep reading for the write up.

Twist the throttle nothing happens, bike just idles= The grip is not seated completely on the internal gears located on the inside end of the grip and on the end of the TBW sensor, OR, the TBW has come apart and has no signal. Either tape the green connector, shrink wrap it, or hard wire.

Check engine light on= Run the diagnostics ( there is a thread in the trouble shooting section on how to do this) I am willing to bet one of these code has shown up:

P1510 - Throttle actuator control limited performance
P2127 - Twist grip position sensor low/open
P2138 - Twist grip position sensor correlation error

The problem to all of these is the green connector it loose and it is not getting enough (or no) signal to the TBW sensor and the TBW sensor cannot send anything to the ECU. Again either tape it, shrink wrap, or hard wire.



Now on to the write up:



After having some of these same issues on my bike after I wired my bars internally, I knew I had to find a better solution. So once again I tore the bars down and pulled out allof my hard work in pulling wires, and started over.

My bike first had several throttle issue which I originally though was a loose connection on the TBW connector in the fairing. I could move the TBW inside the fairing and make the twist grip work correctly... then I would move it some more and my bike was sluggish, and would not rev past 3100 RPM. Then the cruise quit working! So I took another forum members advice (can't remember who exactly it was but, you know who you are) and decided to hard wire the TBW and elminate the green connector.

First I took the bars off the bike. Then I took the big switch housing connector apart again, and pulled the switch housing wires out of the bars. I had to do this because the TBW was in there so tight I did not want to damage it anymore than I had to. When I pulled the TBW harness out of the bars, this is what I saw:





Not pretty! It looks like the inside of the bars has teeth!!! Thats two layers of electrical tape that the bars chewed up from pulling them in and out of the bars. I didnt find any huge cuts or nicks to the wires but the isulation on the wires was scratched pretty bad. Check your wires very carefully to make sure nothing is cut or nicked down to bare wire. Bare wire could cause the wire to ground out on the inside of the bars and short out, or blow out your TBW sensor.

[Donk]

The next thing I did was to remove the first layer of electrical tape off the TBW harness. When you do this it will separate into two harness. The harness with a green connector and one with only two wires and a black connector. The black connector is only for heated grip by HD. I didnt need this so I left it out so I could have more room to pull wires inside the bars.

The two harnesses:


Next is to draw a diagram of the two ends of the green connectors so you know which wires to connect when we cut off the connector. HD has split the wires coming from the sensor into two group with two different color shrink wraps:Black and Yellow. I will now refer to these as Black side wires and yellow side wires. Each side has a white wire, black wire, and red wire. This is what it looks like:



The other end of the harness has six wires also. Blue, brown, red, purple, grey, and black. This is what it looks like:





Here is how the wires will hook up.

Blue Wire------(Black Side) White Wire

Brown Wire----(Black Side) Red Wire

Black Wire-----(Black Side) Black Wire

Grey Wire-----(Yellow Side) Black Wire

Red Wire------(Yellow Side) Red Wire

Purple Wire----(Yellow Side) White Wire

[Donk]

Next cut both ends of the green connector off. I left about and inch on each side in case I decid to use the connector for something else.



Then strip about an inch off the end of each wire.



And the others:



Then you will need to prepare the wires for solder. Twist each wire end tight so the wire does not unravel, and place a peice of shrink tubing on the wire:

[Big_gary]

What guage wire did you use ? did you also eliminate the connector in the fairing ?

[Big_gary]

Nice write up.

[Donk]

Now you need to "tin" the wires. Tinning the wire is simply heating the wire up from the bottom with a soldering iron. Once the wire is really hot, you place some solder on top of the wire, and let the solder melt to flow through the wire and cover it. This pic shows the red and purple wire up top correctly soldered. The rest are still bare. See the difference:



Once you have all the wires tinned you need to run the wires back into the bars.Run your chain/bar snake/string or whatever you use from the throttle top side down to the bottom of the bars. Tape the tinned ends of the wires to the bar snake and pull the wires up to the throttle side.





Now make sure you have the diagram handy and twist the tinned wire ends togther in the correct fashion. USE YOUR DIAGRAM.. DO NOT MIX UP THE WIRES!!!!! The tinned wires will be stiff to move with your bare fingers, so I used two pair of needle nose pliers and twisted them together (also make sure your heat shrink is on the wire too!!!

[Donk]

Now to solder the twisted wires together hold the soldering gununder the wires untill the tin starts to melt off onto each other. Then use just a small amount of solder to make sure everything is good and connected:



Once all are done just put the shrink wrap over your soldering job, and heat it with a heat gun to seal it up.



Now here is the finished product. I wrapped everything again with electrical tape just to be safe.

[Donk]

In the above picture you can see how much less roon the soldered wires are going to take up than the big connector.

Next thing on my bars wa to cut off the black connector from the TBW sensor. Its for the heated grips and I dont need it. Its takin gup pecious space inside my bars,and I need all the room I can get.



Then I taped off the end for safety:






Thats all there is too it folks. Not a hard job at all. Put everything back together and never have to worry about the TBW ever again! As soon as I switched the bike on and fired it up, throttle response was back (and a slight bit quicker than I remember), no more slugish motor, all the DTC's cleared, and my cruise control worked again!!!! Im convinced I have now defeated Harely biggest mistake ever....F%@$ that green connector!!!!!!!!!!!!!!!!!!

Hope this will help someone out there. My best peice of advice is to do this mod the first time you take your bars off instead of the 5th time like I did. It is worth the extra trouble of soldering just to not have to worry about the TBW green connector. Let me know What you guys think.

[Big_gary]

good write up donk ,I chimed in during your write up a little to quick .I did not realize you were not finished. Have you heard of extending the TBW the same way ? I take it you did not eliminate the inside fairing connector.

[Donk]

Originally Posted by Big_gary

good write up donk ,I chimed in during your write up a little to quick .I did not realize you were not finished. Have you heard of extending the TBW the same way ? I take it you did not eliminate the inside fairing connector.

No problem and thanks. I love doing write ups. I elminated it due to the fact of so many issues surrounding the green connector. Mine has been pulled on so much that it wasnt really holding in place that well. I was worried it might wiggle loose inside the fairing later down the road and leave me stranded. It wouldnt be to big of a deal to cut the wires and re solder if I had to take the bars off again (hopefully I never will because Im sick of it. Done it 4 times in the last 2 weeks) LOL