It depends on the harness you have, for example on my 95 325i harness on the x20 the pins for speed signal and tach are:
tachometer- e36x20-pin#20(bk)
engine speed (dme)- e36x20-pin#14(bk/wt)
If you've done the same thing that I have (mine's a 98 m52) and converted to obd1 your pins should be the same if you have an e34 harness or an e36 harness. But where it connects on the c101 could be different since mine is a 318i and yours is a 325is...
tachometer- e36x20-pin#20(bk)
engine speed (dme)- e36x20-pin#14(bk/wt)
If you've done the same thing that I have (mine's a 98 m52) and converted to obd1 your pins should be the same if you have an e34 harness or an e36 harness. But where it connects on the c101 could be different since mine is a 318i and yours is a 325is...
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