OzSTOC
Honda ST1300 Section => Honda ST1300 General Questions => Topic started by: bikebugger on December 02, 2014, 04:05:03 PM
-
Gday all. The last little thing to be fixed on my new-to-me ST is the knock sensor fault. I've seen that for some people it's the wire, for others it's the sensor and for an unlucky few it's the ecu.
My understanding of how the knock sensor works is that it changes resistance with a knock to trigger a response from the ecu. I cant unplug the wire to solve the problem because then there is no connection. I can't ground the wire because then there is no resistance.
My question is:
What is the "normal" resistance for the knock sensor when the engine isnt knocking?
My intention is to buy and fit a resistor direct to the ecu so that it thinks there is a functioning sensor present. If I still get error codes then I know the fault is with the ecu and not the wiring or sensor. I'd like to try this before I pull the bike apart.
cheers!
-
Before you do that, have a look at this video, it explains how a knock sensor works..
https://www.youtube.com/watch?v=L8xRJIWkHuo (https://www.youtube.com/watch?v=L8xRJIWkHuo)
-
Thanks Brock.
Was a little confused because I had seen the piezoelectric term but didn't know how it worked exactly.
In the video it mentions that all knock sensors work in this way so I'm confused to see that a resistor is used successfully a lot on car forums....
Im hopeful I can still find something to trick the ecu but I guess an ac voltage is hard to fake. I have seen one website where a piezo buzzer taped in the engine bay where it would vibrate was used and it worked but this is getting a lot sillier as a potential testing method
-
Im not sure what the resistors do, but the Piezeo sensor is basicaly a microphone used to pick up the sound of knocking. It generates a small voltgae under pressure that the computer uses.
-
here are some ideas om playing around with resistance http://www.autospeed.com/cms/article.html?&A=113160 (http://www.autospeed.com/cms/article.html?&A=113160)