Speedo won't work

Can't get my '83 SC speedometer to work, and I'm wondering if I replaced the wires onto the back of it in the wrong order. I've replaced the speedo sensor on the transaxle, so I know that's not the problem, and I discovered the proper way to mount the sensor, so I know I'm not putting it on backward (which I did the first time around), so I'm left wondering about the wiring.

If I pull the speedometer out of the panel and look at the back of it so that the array of spade terminals is at the right side of the back, the order of wires is:

topmost spade--red/black and red/blue
next spade down--white/red
third spade down--brown/red and brown/black
bottom spade--brown/red and three browns

Can anybody tell me if this is correct? The wiring diagram doesn't help in this instance.

Stephan

Steve,
All of those wires you mentioned are correct. I looked today. Why not lift up the rear tunnel hatch, and see if the spade connectors are in there. Though they might be just on the other side of the fire wall--mine are inside--I would say one is laying on something, or completely off--IT does not matter which wire you comnnect to the module--it SHOULD properly work if wired with a hot and ground from the source of the speedo....and all the wires you mentioned says you do...............

s

Didn't you get it working?
Under what circumstances did it stop again?

i've had this problem before and often it was a crummy splice job somebody did near the tunnel connectors. people forget to unplug them and rip the wires when the engine and trans are removed.

Just putting in my $.02 worth. I had the very same problem with my 83SC. Old speedo was rebuilt for PO and never worked in the vehicle. I located a new speedo and sensor and installed them both in vehicle (I know, a little overkill there). Per the wiring diagram in my Porsche service manual I did the following:

+12V - Red/Blk, Red/Blu
A - Whi/Red
31b - Brn/Red
- - Brn, Brn/Red, Grn

I then unhappily discovered that still nothing worked. I unhooked and rehooked, traced, cussed, fumed. Then I remembered what my dad always told me to never do. I switched the + and -. I drove for less than .1 miles and speedo acted crazy (registered 160). I switched them back, and everything worked great. Must be mentioned that this runs the risk of burning out a part. Best my electrician friend could think of was I needed to break some of the corrosion on the wire fittings and get a better connection.

Just remember that electricity and connections are a funny thing. It all works by FM, as explained to me by some EE and electricians.

David
'83SC Targa