Hi all, I just picked up a bone stock 94 VX hatch. D15Z1. The speedo/odo stopped working today so I popped the hood to look for bad grounds/the speed sensor. On the back of the thermostat housing I saw some bare copper and decided to investigate. This plug on the thermostat housing has two sections stripped, and the plug was twisted so the wires would short. I'm guessing someone was trying to bypass this sensor. My coolant temp. gauge seems to work, but I have yet to hit half way between cold and hot, it seems to show the engine being on the cold side. Why would these sensor wires be stripped like this?


EDIT: After doing some more researching it looks like that is the sensor for triggering the rad. fan. That would make sense, if it's always running my motor would run cooler than normal. Should I just assume the switch is bad and replace it?

 

Heat shrink insulate the two wires, and then check if the fan runs when the connector pins are jumped.

As for the speedometer problem, check whether CEL code 17 is thrown. See CEL Code sticky.

 

My guess is you are correct, the stripped leads are to bypass the ECT switch so rad fan is on anytime ign. is on, if that is the case, repair wiring and replace switch.
It has nothing to do with your temp gauge, that's controlled by the ECT sending unit the one wire "sensor" behind the ECT sensor.

As mentioned, any codes? 94

 

CEL isn't on so I assume no codes. The speedo/odo came back on and only occasionally stop working so I think it is a loose ground or maybe a bad solder joint. I will try pulling the ECT sensor out and testing this weekend.

 

Does the CEL work? See CEL Code sticky thread.