Now with the above stated that you can by a new cluster with the Tranny temp gage in it and it works once installed.....
Then maybe if youhave the electrical diagrams and were pretty good with a multi meter you may be able to figure out which wires to use and what signal the computer is sending to activate the tranny temp gage....
I'll have to check the service manual again. But last time I looked at the gauge wiring, the connector doesn't have nearly enough wires for there to be a dedicated circuit to each gauge and indicator. I'm sure you won't find a wire going to the cluster that is just the trans temp gauge signal. I believe that there are some smarts in the cluster, and there is a serial communications path between the cluster and the PCM. The information needed to update the message center, gauges and indicator lights is sent from the PCM to the cluster, which then decodes it and drives the individual gauges and indicators. At least, that's what I remember reading.
Now, that being said, it's possible that it is the same decoder/driving circuit board in both clusters, and maybe the traces with the decoded gauge information is there in the cluster. It may
be possible to tap into, but it's also quite likely you'll make something smoke while trying.
- Interesting piece of engineering trivia: Did you know that the inner workings of all electronics is based on smoke and mirrors? Yep, it's the smoke inside that makes things work. When you do something wrong and let the smoke out, that's when it stops working!
While the shop manuals detail all of the wires going to/from the gauge cluster, it treats the cluster as a non-servicable unit. The book says if it's broken, replace it. Therefore there is no information on the internals of the unit, other than replacing the light bulbs.
But with that said I think it would be easier to replace the cluster...
Yeah, I'd have to agree with you. (Twice in one day!