Shift Indicator - A/T: Description and Operation

SHIFT INDICATOR (TRANSFER CASE)
Part Time Indicator
A part time indicator is standard equipment on all instrument clusters, but is only functional on vehicles equipped with the optional four-wheel drive system. The part time indicator is located near the upper edge of the instrument cluster overlay, in the upper right quadrant of the cluster. The part time indicator consists of a stenciled cutout of the words "PART TIME" in the opaque layer of the instrument cluster overlay. The dark outer layer of the overlay prevents the indicator from being clearly visible when the lamp is not illuminated. An amber lens behind the cutout in the opaque layer of the overlay causes the "PART TIME" text to appear in amber through the translucent outer layer of the overlay when it is illuminated from behind by a replaceable incandescent bulb and bulb holder unit located on the instrument cluster electronic circuit board. The part time indicator is serviced as a unit with the instrument cluster.

The part time indicator gives an indication to the vehicle operator that a part time operating mode of the four-wheel drive transfer case is selected. On vehicles with the optional Command-Trac four-wheel drive system, the part time indicator lights when the transfer case is engaged in the 4H or 4L positions. On vehicles with the optional Selec-Trac four-wheel drive system, the part time indicator lights when the transfer case is engaged in the 4 X 4 Part Time or 4 Lo positions. This lamp is hard wired on the instrument cluster electronic circuit board, and is controlled by a transfer case switch input to the cluster. The part time indicator bulb receives battery current on the instrument cluster electronic circuit board through the fused ignition switch output (st-run) circuit whenever the ignition switch is in the ON or Start positions; therefore, the lamp will always be OFF when the ignition switch is in any position except ON or Start.

The transfer case switch is connected in series between ground and the 4WD switch sense (part-time) input to the instrument cluster. Refer to Transfer Case for more information on the transfer case switch. The part time indicator can be diagnosed using conventional diagnostic tools and methods.

Full Time Indicator
A full time indicator is standard equipment on all instrument clusters, but is only functional on vehicles equipped with the optional Selec-Trac four-wheel drive system. The full time indicator is located near the upper edge of the instrument cluster overlay, in the upper right quadrant of the cluster. The full time indicator consists of a stenciled cutout of the words "FULL TIME" in the opaque layer of the instrument cluster overlay. The dark outer layer of the overlay prevents the indicator from being clearly visible when the lamp is not illuminated. However, a green lens behind the cutout in the opaque layer of the cluster overlay causes the "FULL TIME" text to appear in green through the translucent outer layer of the overlay when it is illuminated from behind by a replaceable incandescent bulb and bulb holder unit located on the instrument cluster electronic circuit board. The full time indicator is serviced as a unit with the instrument cluster.

The full time indicator gives an indication to the vehicle operator that a full time operating mode of the four-wheel drive transfer case is selected. The full time indicator lights when the Selec-Trac four-wheel drive transfer case is engaged in the 4 X 4 Full Time position. This lamp is hard wired on the instrument cluster electronic circuit board, and is controlled by a transfer case switch input to the cluster. The full time indicator bulb receives battery current on the instrument cluster electronic circuit board through the fused ignition switch output (st-run) circuit whenever the ignition switch is in the ON or Start positions; therefore, the lamp will always be OFF when the ignition switch is in any position except ON or Start.

The transfer case switch is connected in series between ground and the 4WD switch sense (full-time) input to the instrument cluster. Refer to Transfer Case for more information on the transfer case switch. The full time indicator can be diagnosed using conventional diagnostic tools and methods.