Quote:
Originally Posted by FRENCHBLUE72
Can anyone tell me where this green box goes? And whats the deal with the light at then end of it?
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Sorry for not responding sooner... I got caught up working at work and on the truck and hadn't looked at this thread in awhile.
The green box and light you asked about are the VSS signal from the speedometer to the ECM. The light hooks into the back of the instrument cluster at the speedo drive and a gear in the cluster (a reluctor I think it is called) causes the light to pulse at a speed/frequency that is proportional to the vehicle speed and the green box converts that light pulse into a 2000 pulses per mile square wave DC signal to tell the ECM how fast you are going. rfmaster discusses the importance of VSS in post #46 of this thread (I also use the JTR VSS signal generator hooked up at the tranny due to speedo cable wind-up).
Mark