911 ODOMETER Stopped, I replaced it, STILL DOESN'T WORK

[metamusic]

Hello Out There. My '80 SC Odometer stopped working so I replaced it with a rebuilt one. It still does not work. What is the problem. Thanks for your help. Jonathan

[tcar]

Replaced what, the whole speedometer unit?

Did the speedometer work even tho the odometer did not?

What about now?

If nothing works, there is a wiring problem (it's electronic, no cable).

Or a sender problem.

[3.2 CAB]

Do you know that it was actually a completely rebuilt speedometer gauge set assembly?

[metamusic]

I replaced the entire gage with a rebuilt unit. Everything works except the odometer. There is one electrical connection on the back without a lead wire running to it. Do you suppose that is the problem? It is marked 'A'.

[tcar]

On my '80, nothing marked 'A'.

On top 2 lights (red ringed)
Left - WH/GRN stripe
Right - BK/BLU stripe

On bottom 1 light (red ringed)
BK/BLU stripe


On Right side as you look directly at the back:

Top Connection: Left, RD/BL stripe
Right Ditto

2nd Down: Empty

3rd Down: WH/RD stripe

4th Down: Left - BK/BRN stripe
Right - BRN/RD stripe

5th Down: Left - BRN/RD strip
Right - 3 solid BRN


Hope this helps.

[metamusic]

The second down connection you mentioned is marked 'A' on my speedo. It looks like it is supposed to be empty. My gage only has four connections though (apart from the lights). The last two are piggy-backed on the same connection post. Thanks for the info. Do you suppose that I have been sold a gage as 'Rebuilt' that actually does not work?

[metamusic]

Hello, to clarify- by 'EMPTY' do you mean that there is no connection at all. I have attached a picture. Are these the positions 1-5 you are referring to? Thanks, Jonathan

[tcar]

Yes. Empty. 2nd position down is blank.

You can ignore the 'Right' and 'Left' on positions 1, 3, 4, and 5, just so those wires connect to those terminals. I just told you how mine was set up.

[metamusic]

I think that might solve my problem. I do not have a wire connected to position #3. My guess is that the missing wire is for the odometer. Thanks for your help.

[tcar]

Hope you understand my color code...

RD - Red
BK - Black
BL or BLU - Blue
BRN - Brown
WH - White

...and for what it's worth, solid Brown is the Ground on these cars.

Good Luck.

[metamusic]

Hello Tcar, So I pulled my gage again in an attempt to inspect the wiring. Everything is exactly as you said except the White/Red Stripe wire is missing. My car is EURO, however, I have 180MPH speedo. do you suppose that is the problem? You mentioned that the white/red stripe wire connects third from the top. Instead nothing is connected. Any ideas?

[tcar]

Can you look around behind the dash and see if you find one?

Or another wire that's not connected to anything?

I'll look at wiring diagram and try to see what the WH/RD stripe goes to.

Mine has a 150mph speedo. Converted from 85mph speedo.

Anyone else on here know?

[metamusic]

I pulled every gage in search of the missing wire. No wires are disconnected or cut, especially not white/red stripe wire.

[javadog]

If your speedometer needle works, and indicates the correct speed, and the odometer does not work, the problem is in the gauge.

JR

[metamusic]

Thank you for those enlightening words. Yes, my speedo does work. The odometer does not. I guess I will either re-build my gage, or buy another rebuilt one. The first 'rebuilt' gage I bought did not work either so I figured the problem must be in the wiring.

[rick-l]

Adventurous???
Odometer Gear replacement for Electronic Speedometers (long)

[Porsche_monkey]

Originally Posted by rick-l

Adventurous???

That is a pretty easy repair. My took less than 45 minutes.

[Britain Smith]

Sorry to dig up an old thread, but I need some assitance wiring up a 915 electronic tach/transmission in an early car.

The speedo sensor has two output wires:

Green
Brown

The Electronic Speedo has 4 input connections:

Top Connection: RD/BL stripe -- This is +12V ( should be able to just get this from one of the bulb connections right?)

2nd Down: Empty

3rd Down: WH/RD stripe -- What is this for???

4th Down: Left - BK/BRN stripe -- I believe this one is labeled 31b and is where the green wire from the sensor goes, right??Right - BRN/RD stripe

5th Down: Left - BRN/RD strip -- This is ground. Does the brown wire from the trans sensor need to be grounded here directly??
Right - 3 solid BRN


Thanks for the assistance,
Britain

[Britain Smith]

Anyone lend a hand on this one?

-Britain

[euro911sc]

I'll take a shot from work...

Diagrams are from an '82 drawing.

The Tach Wiring:


The Speedo Wiring:



From the second pic you can see that the green wire from the sensor goes to 31b. The gound for the sensor goes to the terminal marked '-' on the speedo. In the diagram you should see a small '-' on the connection just below '+12v'. There are two power wires that come off the ignition Sw and go into the Speedo. These are the BK/BL 0,5 wires to the left of the '+12v' in the diagram. The +12 0,5 RE/BK comes from Fuse 13 and connect to the '+12v'. The other wire that connect to '+12v', a 0,75 RE/BL, comes from '15' on the milage counter. The WT/GN wire comes in from the light sw.


Hope this helps some

Best regards,

Michael