I'm about to install a new head unit with GPS. It has a speedo sensor wire that needs to connected (well it doesn't need it, but it helps with GPS when going through tunnels and other times when you loose a signal).

My question is, where can i find the speedo wire or sensor? Does it come through the floor of the car or by the ebrake? Here is a pic from the 94 wiring diagram with what I'm looking for highlighted.

 

Connector C1-08 is on the left/driver's side of the transmission.

Connector X-14 is in the passenger footwell.

I don't know how the wires between the two are routed but you should be able to follow them from the trans. I would guess they run up to the firewall and enter through the one of the holes in the pass. footwell.

 

There is also a speedo input to the ECU, that might be one of the easier wires to get to. Look at the ECU wiring diagram.

Dale

 

Instead of running directly to the speedo wire on the previously mentioned plug, I've decided just to tap into the back of the gauge unit because its so close to the radio.

I've done a little research but am not sure which wire to tap into. It looks like I have two options on the plug that connects to the speedo. Highlighted in Yellow and Blue. Which one should I tap into?

 

Hmm, I had a look at the electric body troubleshooting manual and it says the sensor generates a varying 5v signal between the two leads of the sensor. Doesn't say which one is the reference voltage of 5v and which is the signal.

Also looked at the FSM page F-29. Shows that the speedo signal is reported to the ECU by way of cluster terminal 3E to ECU terminal 1M. I'd look at that last wire as the signal.

 

Great, now three options haha.. Maybe I should just go with 3E then?

I may end up just leaving it off. It's not needed for the GPS, it just helps out when going through tunnels and whatnot.