I have a 1981 Rabbit pickup, diesel. Recently bought an instrument cluster from a 1982 Cabriolet gas version with tachometer ... the 1981's did not have the tach, from what I've gathered so far.
In comparing clusters, the gas-tach one looks almost identical to the original one from my diesel pickup, except for a couple of items related to the circuit board.
1. Tach cluster has 3 wires coming out from within the 'box' adjacent to the speedometer, which 'appear' to have something to do with the speedo, and are screwed into the circuit board at that point. Colors are red, white and blue.
2. The majority of … what I will refer to as 'pins' on the tach circuit board … are the same in most instances, with only a couple of pins not being present. This circuit board is much closer to original than other diesel versions I have ... by far … with one presently installed, and seem to be functioning A-OK.
I 'think' the extra pins on my original circuit board, may have been for the a/c that was in the pickup; whereas am 'presuming' the Cabriolet did not have a/c.
3. Original board from pickup had clock, and was connected with 2 'prongs' of the board that went upward and attached to clock by screws.
Board of Cabriolet, with tach in lieu of clock, has these 2 'prongs' cut ... or they appear to have been cut ... since I see no screw holes for attachment.
Nor do I see any plug, spade, etc. for connection on the back of the tach.
Sorry about all the jibberish, but felt you need to know the background before my questions.
Does anyone have experience with this process of taking a VW rabbit, etc. version of tach and installing it into the diesel. OH ... by the way; I do have the proper alternator with the'W' terminal, and will be installing it.
Not seeing any difference in gas vs diesel version of circuit board, is there something else I need to know or be aware of? In other words, will it be accepted without frying my wiring or the tach or other items in the dash cluster.
How is the tachometer connected to the electrical system? As mentioned, tach displays no terminal or plug in the rear.
Any ideas what the 3-wires I mentioned are for?
I do have wiring schematics of the 81 gas and diesel, but not of the 82 versions. Does anyone have them that they are willing to share? Don't really desire to have to buy the 1982 Bentley, just for this one usage. If need be, I can scan mine and send along to compare.
Would appreciate any and all responses to this. Would like to get started swapping the clock from my original cluster over with the tachometer. When all's said and done, will have some extra cluster parts no doubt.
Thanks !!!