You have 4 wires - no more, no less - to be concerned with for the A/S: A power (Red/White), a ground (Black), an upshift wire (Light Green/Red), and a downshift (Yellow/Light Blue) wire.
Simplest way to grab power is to tap the Red/White wire of the DLC (Data Link Connector) - easier than adding a terminal to the connector in the BCM that the How-To's talk about.
For ground - put a ring terminal on that wire and attach it to one of the two ground studs just above the lower edge of the console plastic to the right of your ankle when your foot is on the gas pedal.
The upshift (Light Green/Red) and downshift (Yellow/Light Blue) wires should be tapped to the correct wires on C106 (located on the cluster of connectors to the left of the brake pedal - the left top connector above the blue connector, 10 pins) - Light Green/Red (up shift) and Yellow (down shift). Those two wires are adjacent to each other - the Light Green/Red one is on the last pin of one of the rows, and the Yellow is immediately adjacent to it.
I suggest you remove the single screw (10mm hex head - might be 8mm, but I think 10) attaching the panel of connectors to a bracket to work with C106, then re-attach when done. You won't have much length of wires to work with - just carefully work with those wires (unwrap some harness tape, etc.) to pull a little slack in them for a service loop to splice to. Tight, but do-able.
On some years, the up and down shift wires were not run to C106 from the PCM on cars that didn't come from the factory with A/S, so you would have to run your own wires from the PCM If that's the case, you might just as well bypass C106 and make a direct run from the PCM (under the hood) to the shifter A/S module.
I'm assuming that the wires that would go from C106 to the shifter A/S module are not in your car - that too may vary by year for cars without A/S. But if they are there, the wire that is yellow on one side (PCM side) of C106 will be Yellow/Light Blue on the other side (shifter side). Just be careful not to grab the Yellow/*DARK* Blue wire that is also on C106. Sometimes dark blue and light blue can be almost indistinguishable on these wires. If it's the one immediately adjacent to the Light Green/Red wire, you know that's the correct one.
You have an FSM? You really should have one if only for section 8W that contains the schematics, connector pinouts, and other essential wiring info.
Oh - also - hopefully not insulting you if you already know this stuff, but either make soldered connections, or use *RED* T-taps. Blue T-taps are for larger wires and will make very unreliable connections on these smaller wires. Red (T-taps or other tapping devices) only if that's what you use to splice.
'98 LXi - Later Concorde gages (black w/ chrome rings)/'99 LX - LHS gages (white) - HIR bulbs
Last edited by peva; 09-24-2011 at 08:00 AM.