For my GTUs -> TII swap (S5 -> S5 for anyone who does not know) I bought a turbo gauge cluster so I could have the boost gauge (not that it matters because I will have a FCD on the car) and the correct tachometer. I want to keep the odometer/spedo the same so it shows correct chassis mileage. Here is where my question lies.

I took out both speedo’s (one for the N/A and the one for the turbo). On the backside of the spedo are these little switches next to the odometers, these switches are clicked on and off by (for a lack of better words) plastic cams that come off the rod of the odometers. There is one odometer at the top that is only 5 digits and one below it (this is the one you see) that has 6 digits. The N/A spedo only has a switch on the top odometer and the turbo one has switches on both of them.

I would think that these switches are for when the car is new and it hits those first “scheduled tune-up” periods and throws up the check engine light. Does anyone know first off what exactly those switches do?

I have seen turbo guys run the N/A gauge cluster so they could have the 9k RPM tach. So I am assuming I will have no ill will if I swap the N/A spedo? The circuit board of both gauge clusters are identical. The only difference on the back circuit board is the N/A does not have a screw placed in the hole where that 2nd switch is but the connection point and hole are there. This might be an odd question sorry if it does not sound right I can clarify if someone does not understand.

Thanks

Dana “The evil snail GTUs ”

 

No, the second odometers are for the 20K miles switch to send a signal to the ECU when the car has hit 20K miles. The ECU modifies the way the car runs after that.

 

When you say 2nd odometer you are talking about the top one right? Well you learn something new every day. Just out of curiosity how does it modify the way the car runs? Does it modify the fuel curve, ignition, what? So if that is what the top switch does what does the bottom switch do? So I should be fine to swap the spedo’s then.

- Dana "So many ?'s so little time "

 

Ted (Reted) would know what it does exactly, but I imagine that it is related to the break in of the cats and engine.

 

Too bad Henrik isn't in here too much - I've heard he cracked the stock ECU code off the TeamFC3S.Org forums.

The 20k miles switch just switches between two settings.&nbsp My bet would be a more rich fuel map and conservative ignition timing prior to the switch being tripped...



-Ted