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2009 IAT Sensor problem

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While removing my subframe/airbox the other day, I accidentally pulled the wires out of the grey clip connector that plugs into the IAT (intake air temperature) sensor in the bottom left of the airbox. I noticed there were two different colored wires, and I made my best attempt to plug them back in, based on how they were twisted. Well I must have guessed wrong because as soon as I got it back together and fired it up, I had 9 blinks on my MIL, indicating an IAT malfunction. I called a local honda tech friend, who looked up the wiring and told me to reverse them (grey/blue wire to the outside, green/red to the inside). So I did, but the 9 blinks won't go away now.

Is it possible I shorted out the sensor itself by starting it with the wiring reversed? Could the wiring be bad? Or perhaps the computer is still registering a previous error that needs to be cleared? I did this right before track night, and the bike ran fine all night (although it seemed much harder to start), but the 9 blinks were annoying as heck.

Electronics are not my strong suit, so any help would be much appreciated.

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doesnt matter which pin is which.

did the wire pull ouf the terminal or did the wire and terminal come out of the plug?

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The two wires actually pulled out of the grey terminal (which you can unclip from the sensor...if properly removing the airbox).

So it doesn't matter which wire is connected to which post?

Maybe the wires aren't making proper contact anymore since they came out of the terminal...?

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Looking at your question closer, I understand now what you're asking. The wires did not pull out of their metal terminals (on the end of the wires), they just pulled out of the grey plug.

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Ok, I've checked all the wiring, and it all looks good. I even plugged the two wire terminals directly into the pins in the sensor to be sure they were making contact. Same thing...9 blinks. I ordered a new IAT sensor, but it won't be here for a few days.

I just can't imagine that the sensor itself is bad, since it was working fine before I accidentally pulled the wire terminals out of the plug, but I don't know what else to do.

Is there an easy way to reset the computer module, without requiring the $400 programer from Honda (which I don't have and my dealer can't find theirs!)? The only other thing I can think of is that the computer is still registering that previous error. However, numerous other guys on here have had the 9 blinks after forgetting to plug their IAT back in after subframe removal, and their blinks apparently went away.

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Bought whole new IAT sensor, hooked it up....9 blinks. I don't know what else to do. It looks like I might have to buy a whole new complete wiring harness, because I can't find any break in the wire anywhere, nor did I ever do anything that would have caused a break.

Tried resetting the memory of the ECM as instructed in the shop manual...no luck.:banana:

Any ideas out there?

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you need to check continuity on those 2 wires with a meter. put one clip on the end and stick a straight pin through the insulation a few inches from the end and put the other clip on the pin. after the test is done you should seal the pinhole you made with some silicone. like eddie said, most likely a broken wire. hope this helps, jim.

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i have done this myself, in my case the wires were not broken but i had not pushed the pins in far enough into the grey plug, when you try to eliminate a broken wire i connected the pins without the grey plug and a piece of paper between the 2 pins so they could not touch because they are very close together, give this a shot it cost $0 :banana:

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Dearden225, you made my day. Your paper idea solved the mystery. I tested the continuity of that entire circuit and everything was fine, so I was perplexed, until I tried the paper trick between the terminals and realized that they were touching...even inside the gray clip...because they weren't pushed in far enough.:thumbsup: Had to really push them hard with needlenose pliers to get them in all the way. Finally the circuit is connecting through the IAT sensor, instead of jumping before it.

Thanks to all for your suggestions.

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