1) Turn ignition switch to RUN position. Move gearshift lever
into Park. Move mirror switch to MAXIMUM, ON or MIRROR position, if
necessary. Cover ambient light sensor (windshield side of mirror) with
a dark cloth. Shine light on headlight sensor (on mirror side). Mirror
should gradually darken.

2) Move gearshift lever into Reverse. Mirror should gradually
lighten to a clear state. Move gearshift lever into Park. Mirror
should gradually darken. Remove cloth and light. Mirror should
gradually lighten to a clear state.

AUTOMATIC DIMMING MIRROR DOES NOT LIGHTEN OR DARKEN
PROPERLY
1) Turn ignition off. Remove and check CHIME fuse 1D (15-amp)
located in instrument panel fuse block. If fuse is okay, go to step
3).If fuse is not okay, go to next step.
2) Disconnect mirror connector. Replace CHIME fuse. Turn
ignition on for 10 seconds, then turn ignition off. Check CHIME fuse.
If fuse is okay, recheck system operation. Perform
AUTOMATIC DAY/NIGHT MIRROR SYSTEM CHECK. If fuse is blown, repair
short to ground in Pink wire between automatic day/night mirror and
instrument panel fuse block.
3) Turn ignition switch to RUN position. Connect test light
between automatic day/night mirror harness connector terminal No. 1
(Pink/Black wire) and ground. If test light illuminates, go to next
step. If test light does not illuminate, repair open in Pink/Black or
Pink wire between automatic day/night mirror and instrument panel fuse
block.
4) Connect test light between automatic day/night mirror
harness connector terminal No. 2 (Black or Black/White wire) and
battery voltage. If test light illuminates, replace mirror. See
REARVIEW MIRROR under REMOVAL & INSTALLATION. If test light does not
illuminate, repair open in Black or Black/White wire between automatic
day/night mirror and ground.

IMPROPER OPERATION IN REVERSE
1) Turn ignition off. Disconnect mirror connector. Remove and
inspect SIG/BU/LPS BTSI/LCM fuse 1B (20-amp) located in instrument
panel fuse block. If fuse is okay, go to step 3). If fuse is not okay,
go to next step.
2) Replace SIG/BU/LPS BTSI/LCM fuse. Turn ignition on for 10
seconds, then turn ignition off. Check SIG/BU/LPS BTSI/LCM fuse. If
fuse is okay, recheck system operation. Perform
AUTOMATIC DAY/NIGHT MIRROR SYSTEM CHECK. If fuse is blown, repair
short to ground in Pink wire between Park/Neutral Position (PNP)
switch and instrument panel fuse block.
3) Check for poor connections at Park/Neutral Position (PNP)
switch. Repair as necessary. Check operation of back-up lights. If
back-up lights are functioning properly, go to next step. If back-up
lights are not functioning properly, check for open in Pink wire
between PNP switch and instrument panel fuse block. If Pink wire is
okay, replace PNP switch.
4) Using DVOM, check resistance between PNP switch connector
C1 terminal "F" (Light Green wire) and automatic day/night mirror
terminal No. 3 (Light Green wire). If resistance is 5 ohms or less, go
to next step. If resistance is not 5 ohms or less, repair open in
Light Green wire between PNP switch and automatic day/night mirror.
Perform AUTOMATIC DAY/NIGHT MIRROR SYSTEM CHECK.
5) Check resistance between automatic day/night mirror
harness connector terminal No. 2 (Black or Black/White wire) and
ground. If resistance is 5 ohms or less, replace mirror. See
procedures in REARVIEW MIRROR under REMOVAL & INSTALLATION. Perform
AUTOMATIC DAY/NIGHT MIRROR SYSTEM CHECK. If resistance is greater than
5 ohms, repair open in Black or Black/White wire between automatic
day/night mirror and ground. Perform
AUTOMATIC DAY/NIGHT MIRROR SYSTEM CHECK.