I don't have the part number.
Is Fuse 1 blown?
If not, you can trouble shoot it for bad A/S switch or wire. Disconnect the A/S switch. The black wire at the switch should measure continuity (low resistance) to ground. The other two wires should measure 12 volts. I you don't get that, there is a broken wire or otherwise bad connection (or blown Fuse 1).
If those 3 measurements are good, with the engine running and gear selector in A/S position (brakes on, of course), you should see the gear indicator in the cluster move from 1 to 2 if you short the up-shift (light green/red) wire to ground. You should be able to shift back and forth between 1 and 2 alternately shorting the up- and down-shift wires to the ground wire. If that all works right, then the switch is the problem.
Are there any codes? Some codes may cause A/S to be disabled (not sure - but possible).
'98 LXi - Later Concorde gages (black w/ chrome rings)/'99 LX - LHS gages (white) - HIR bulbs