I had bad odometer But speedo worked. Replaced odometer gear and was bench tested by NorthHollywood, but when installed in the car again neither the speedo nor the odometer work. Is ther a fuse for the speedo? I'd so where is it? OR How can I diagnose the problem and solution? Help!

 

There are green and black leads to the connectors on the speedometer, and a power and ground lead, as well. Pull out the speedometer and confirm all 4 leads are plugged in to the correct lugs. If the harness was tugged on in the changeover, also pull the shift linkage cover in front of the back seat and be sure the speedometer leads are still plugged in there.

 

Pulled the cover in the rear seat area and everything hooked up. Pulled the sleep again and all wires are hooked up and as they were market when taking it out. Any way to test if it is sending current when moving?

 

Marked all wiring when I took the speedo out and did no other work at the time. Tried taking it out again now and reinstalling with that being the last wire attached, and still not working. I did drive the car with the speedo disconnected, could I have shorted anything out driving with wire ends exposed? No fuse for it?

 

What do you mean the If the IC is broken? I don' see a green wire in your picture.

 

Car is 1985 as stated in the subject line.

Ok took it out again and see the green wire. Will check the ground to see if there if continuity.still do not what the IC is though ... Anyone ? Is there a way to tell? Have disconnected all wires and tried reconnecting in a different order (right location just connecting in recommended sequence). I never had the car running or powered up with only some wires connected so why would attaching that wire last make a difference when not running? Hmmm...

 

These speedometer contain an (IC) Integrated Circuit.

Most likely, to count the pulses from the X-mitter.

Give North Hollywood a call. Ask for Kevin.

And, can you borrow another speedometer from another car.................

 

Thanks 86targa. I will check with Kevin at North Hollywood again. I have been chatting with anothenlocal Porsche guy but he is not yet jumping at the thought of swapping speedo for test despite thebfact he has had his our for repairs before.

Will try again

 

Just tonight noticed that the green light at the top of the speedo comes on when park lights are on, but goes off again when the lights are turned on full. Is this normal? Or could it be another diagnosis point?

Found another 85 In town to swap speedos with to test speedo versus sender etc, but he is not back in town for a few more days. Hopefully solved soon before i get a speeding ticket.

 

Thanks ... Just checking. Appreciate you quick replies and help.