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Finished a cooling system overhaul and immediately after lost speedo,mpg, and odometer. My abs light is on but that has been on for a while. Did I forget to plug something in? My assumption is that my rear sensor is bad, maybe even just dirty. But I don't know which sensor is for the speedo, as some forums say left and others say right side. I know my car has 1 sensor on my U.S. driver side that goes from the junction box to the wheel. And two sensors from the junction box on the passenger side. Any help out there?
 

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The side with the two sensors one is for the brake the other is a wheel speed sensor. I'm not sure what tools you have at your disposal but you can either unplug the sensors at the harness connection at the wheel well. Or you can goto the abs module and unplug that...find the appropriate pin for the wheel speed sensor and use a multimeter to test the speed sensor. You'll need someone to spin the wheel for you obviously. I'm pretty sure the speed sensors generate a sine wave (AC) so make sure u set your meter accordingly. Make sure you don't spread the female connections inside as you can cause harness issues after your done. You need to just rest the probe on top of the pin.
It would be a lot better to use a scope to see the wave because multimeters cannot see frequencies very fast and will only give you an avg.
 
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