Self diagnosis switch-164

[Chip Schug <cschug@xxxxxxxxxx>]

Where is the self diagnosis switch on the 164?  Is the the square on the
back left (underneath) of the steering column or the circle in the
middle (underneath) of steering column?

If it is the square, mine is missing.  All I have is a RED connector
with a light blue & green striped wire and a black wire.

Please advise.

Chip
'91 164L auto

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