I have a 2011 FLTRX 103 w/ABS & security (the Power Pack I believe they called it). I bought it new. Vance and Hines power duals, high output round mufflers, heavy breather air cleaner, Screamin Eagle tuner, J&M speakers and amp.

It ran fine last year on my last ride before putting it away for the winter. It sleeps in my heated basement garage, covered.

Overthe winter I put 12” mayhem bars on and custom dynamics pro beam tail light bulb replacements and the blue plug and play custom dynamics stabilizer.

First ride after installing the bars and bulbs it threw a P0117 code (no engine light though). P0117 - ET sensor low.

The bike bogs / cuts out on a quick blip of the throttle but if I roll the throttle slow it revs up and I can run at higher RPM’s fine. It feels like it is in a “cold” mode (feels like the choke is on too long in a carb). The “hot” idle is also high, about 1150-1200 rpm. Everything else on the bike works fine.

I have the service manual and the electrical diagnostic manual.

I replaced the ET sensor and it ran good for one ride around the block, about 15min ride. I thought I had it, the next ride it wasn’t running right again and threw the P0117 code again, again no engine light. I’ve spent the past few days digging into the wiring harnesses, testing for shorts, opens, voltages, resistances, and inspecting the wires both visually and feeling for weak spots. I’ve also cleared the codes, pulled the main fuse multiple times and the code comes back as soon as you turn the key on.

I have performed all the tests in the diagnostic manual for this code (as well as P0118, ET sensor high). And it has passed every test. The last suggestion in the book is replace ECM.

I have also changed the fuel filterand the check valve and line in the tank, it appeared to have a nick, but after I got it out it was fine, I replaced in anyways.

It is a very simple circuit. Pink/yellow from ECM to ET sensor, Black/white from ECM to a 3 way split. From the split there is a separate wire to the ET sensor, the twist grip, and throttle body. None of these wires has a short to ground, or another wire as far as I can tell. Unplugging the other two sensors on the Black/white doesn’t change the P0117code.

Im at a loss here. I can’t believe the ECM would just develop a problem. I also have a hard time being defeated and taking it to he dealer, to have hem charge me to do all the same tests I have just done, just to tell me it’s the ECM. I also don’t want to “parts change” the ECM.

Are ECM failures common? Is there anything else I could try? I’m thinking about trying a new TMAP sensor, I believe the ECM compares the temp reading from both of these sensors. Could the TMAP be faulty making the ECM think he ET sensor is off?

I don’t have a digital tech to see the temperature values the 2 sensors are reporting, however the resistance of the temp side of he TMAP is about half the resistance of the ET sensor (possibly vice verse, that was a couple days ago)

Sorry for the long post, I was trying to cover the questions that hopefully follow.

Any help would be greatly appreciated!

Tom.

 

If you have the SE tuner, you can monitor the ET sensor readings. Just because it shows a ET sensor code it doesn’t mean the sensor is bad—it means it detected an issue with the circuit. Think bad connection or broken strands within the insulation.

 

I have the little orange SE tuner. How do you monitor the temp with that. The dealer did the original install on that.

 

You need the software ( I think it’s still available online) and the cables. With bike hooked up to a PC you can monitor all parameters in the data section of the software.

 

The engine temp sensor uses the same ground wire as the TGS, I suspect when you did the bars, you mucked up the connection. Check the throttle wiring. Make sure you don't have a random short to something else.. I would expect that you might see TGS errors but then maybe not.

 

Even with the TGS disconnected (eliminating the harness in the bars) i'm getting the P0117 code. Obviously when the TGS is disconnected i then get the several TGS codes but also still getting the P0117.

I've checked for continuity between the Black/white (low side ground) wire (in the bars i believe it switches to just black) and the other 5 pins as well as to ground and there is no continuity. I have 5V at the ET sensor plug, I would expect the voltage to be different if there was a wire shorted to ground or another wire (this is actually a test the diagnostic manual outlines).

Does anyone know if there is a chart showing resistance ranges for the ET sensor at various temperatures?

Is there anything that could induce a failure in the sensor? I noticed last night that both the new and old ET sensors were showing the approximately same value, however when i got the new sensor i checked the resistance of both and they were both quite different.

 

 

My sensor resistance value agrees with the numbers in the chart, at least it does at 68. Anyone know why the voltage resets to 4.xx at around 104deg F.

Im going to try to test the voltage somehow without the breakout box. Thinking I can disassemble the 2 wire connector at the ET sensor. I also picked up a new TMAP today. Dealer didn’t have the wires to hook up my tuner. They also quoted me $360 plus an hour later to swap out and program the ECM. Not as bad as I thought.

thanks for the chart.

 

Voltage is measured by a simple resistor divider with the thermistor (head temp sensor) connected to ground and a pull-up resistor. To extend the range the ECM measurement, a second resistor is switched in as an additional pull-up since the voltage is getting real low and so the measurement becomes less accurate.

BTW, If while monitoring you don't see the voltage switch around the specified spot in the table, the ECU is bad as the extra pullup resistor system is not working.

 

You replaced the temp sensor and got the same END result. Possibly when you replaced the sensor the connection was temporarily made so it appeared to be fixed...until heat and vibration caused failure.
My guess is you have an intermittent electrical connection issue. Connector pin/socket not completely locked into connector housing at the sensor or ECM? A wire that has broken inside the casing will make contact when cold but when heated from the engine and exhaust, will break connection?
Bob