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NISTECH »
https://forums.nicoclub.com/nistech-u7581.html
Wed Jan 21, 2004 1:38 pm
the speed sensor is the speedometer head it self. first start by removing the cable from the trans and manually spin it while someone watches the speedo if it doesnt register any speed you have to remove the speedo and look at the back of it. If the plastic around the post the speedo cable goes in is cracked you are in need of a speedo head. in some rare cases I have been able to get one of those working by cleaning the outer surface of the plastic with isopropal alchol and wrapped it very tight with electrical tape.
If the speedo does register but you still have the check engine liht for that code the electrical portion of it is at fault. sometimes cold soldier joints are the cause and can be repaired by resoldiering it. you just have to look closely for cracking in the solider mounds could be any of them.