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F29 is a 5A fuse in the fuse panel under the dash. It supplies power to the autolamp sensor, transmission control switch, central security module, and belt minder module. The autolamp sensor monitors ambient light to control autolamp relays. As the light level decreases, sensor resistance increases to preset amount energizing relays, turning on headlamps and intrument illumination lamps. The sensor controls the headlamp relay which is in the auxillary relay box 3. Good luck!
My truck does the same thing, so If i take out that fuse, I can do it manually, and it will stop doing it automatically?
Taking out the fuse will shut down more than the AL sensor. I listed all circuits supplied by F29. What do you mean by your question? Does your truck have adjustable sensitivity for the AL? Mine is not adjustable, just a position of the headlight switch. If I turn the switch to headlights on, then AL is off.
Taking out the fuse will shut down more than the AL sensor. I listed all circuits supplied by F29. What do you mean by your question? Does your truck have adjustable sensitivity for the AL? Mine is not adjustable, just a position of the headlight switch. If I turn the switch to headlights on, then AL is off.
On my truck 99 F150, the headlight turn on automatically, during the day or night, when the switch is on or off, the headlights are always on
If your headlight switch does not have a AL position, then you may have a truck equipped with DRL (daytime running lamps) which is something entirely different than the AL system.
4xnut, do you have any problems with the other circuits that are supplied by F29? If not, then I would suspect a problem with the AL sensor. The AL sensor is up on top of the dash near the windshield. There is a light green/yellow stripe wire that goes to the relay that turns on the headlamps. To test the relay, simply use a jumper wire to ground this wire. If the headlamps illuminate with this wire grounded, then the relay is good and the AL sensor is bad. Good luck!
Last edited by KingRanchMan02; Nov 16, 2007 at 10:16 AM.