2002 2.7 swap into early 2000 986 temp sensor wiring
 

As the title states, I swapped a 2002 2.7L into an early production 2000 2.7L Boxster. The wiring harness was transferred along with the engine. It runs and drives fine, but I have two issues. Both issues appeared when the swap was made. (excuse me if this not the correct forum)

First, the temperature gauge does not read on the dash. I can make it sweep with a diagnostic tool, so I know the gauge is working. The temp sensor in the 2000 has four wires. The 2002 has two.

The second issue is that the dash gear selector indicator flashes D-4 and the paddle shifters on the steering wheel do not work. (This could be a separate issue as I also swapped the steering wheels on the two cars to put the three spoke onto the 2000 in place of the 4 spoke. I have changed the transmission multifunction switch - it made no difference.

I'm thinking I should have put the wiring harness and temperature sensor from the 2000 2.7 on the 2002 2.7L before doing the swap. Now that the engine is in the car, what suggestions do you have?

Thanks,
Joe

Had to refer back to the spreadsheet I put together when I swapped a 2002 3.6 into a 2000 (3.4) 996 to remember what I did.

In that case, I kept the 2000 harness and just added a couple of wires to run the variable valve lift and changed some pin locations at the DME connectors to work with the 7.8 Motronic insead of the 7.2 that came with the 2000.

So the original temperature sensor wiring was retained, and the temperature sensor from the 3.4 was moved to the 3.6.

The below information was obtained using a "PST2 clone". Key on, engine off. BTW, I've seen that combination abbreviated as KOEO, but to me that would be Key on, Engine on, not off. Appreciate someone setting me straight on the correct abbreviations.

Regarding the temperature gauge - When reading the DME I can see that the engine knows the temperature.

Regarding the transmission gear display - When communicating with the transmission computer (does that have a name?) I found a fault for "Instrument Cluster Activation", however, when activating inputs, I can select each gear and it WILL display correctly on the instrument cluster. When I read the Instrument Cluster, I do not see where to activate the transmission. I'll do some more research on this topic, but wanted to report all of this while it was fresh in my mind.