Test E: Automatic Dimming Function Inoperative
- Remove fuses 14 (5-amp) and No. 30 (15-amp) from instrument panel fuse box. If both fuses are okay, go to next step. If either fuse is blown, replace fuses and go to step 3)
- Install fuses. Place transmission in Park. Turn ignition switch to RUN position. Place mirror autolamp delay in MAX position. If inside mirror darkens, system is okay at this time. If mirror does not darken, go to step 4).
- Turn ignition switch to LOCK position. Disconnect inside mirror harness connector. Measure voltage at terminal No. 5 (Brown/Light Green wire) at inside mirror harness connector. See Fig 1
. If battery voltage exists, go to next step. If battery voltage does not exist, repair power distribution circuit. See appropriate POWER DISTRIBUTION wiring diagram in SYSTEM WIRING DIAGRAMS article in the WIRING DIAGRAMS section.
- Measure voltage at terminal No. 6 (Red/Yellow wire) at inside mirror harness connector. See Fig 1
. If battery voltage exists, go to next step. If battery voltage does not exist, repair power distribution circuit. See appropriate POWER DISTRIBUTION wiring diagram in SYSTEM WIRING DIAGRAMS article in the WIRING DIAGRAMS section.
- Measure resistance between ground and terminal No. 4 (Black wire) at inside mirror harness connector. If resistance is 5 ohms or less, go to next step. If resistance is greater than 5 ohms, repair open in Black wire.
- Turn ignition switch to RUN position. Measure voltage at terminal No. 3 (Black/Pink wire) at inside mirror harness connector. Place transmission in Reverse. If battery voltage exists, go to next step. If battery voltage does not exist, reverse light circuit. See appropriate BACK-UP LIGHTS wiring diagram in SYSTEM WIRING DIAGRAMS article in the WIRING DIAGRAMS section.
- Measure voltage at terminal No. 3 (Black/Pink wire) at inside mirror harness connector. Place transmission in all other gears. If battery voltage exists, repair short to voltage in Black/Pink wire or adjust/replace transmission range sensor as necessary. If battery voltage does not exist, replace inside mirror assembly.
Courtesy of FORD MOTOR CO.