2002 t-bird autolamp functionality


Recently acquired an 02 bird and am wondering about the autolamp functionality/use and whether or not it is working correctly.

The scenario is all within the same driving cycle (i.e. car (or key) is not turned off).
Autolamp switch is on.
Based on ambient light conditions the lights will cycle properly for 1.5 cycles. In other words they will turn on, turn off, turn on as expected based on ambient light conditions. However once they come on the second time, they won't automatically turn off. I can shut off by turning off the autolamp switch but they will come back on when I turn the autolamp switch back on. The only way to "fix" it is to cycle the ignition key. That will reset the system but only back to being able to cycle automatically for 1.5 cycles.

Can anyone confirm this is normal for 02 birds? Clearly the system is working in some fashion but this doesn't seem right unless the system says (the lights have turned on twice within a certain time period, I'm going to leave them on if autolamp = on and car has not been shut down). I know the 03-05 birds use a different FEM so I'm hoping someone has a 02 to test using something to cover the sensor (assuming you are in daylight). I have no other issues that would indicate the FEM is going bad. I do know the ambient light sensor and the headlight on/off switch go through the instrument cluster. I have no IC issues either. I've used a 3rd party app called ForScan to run diagnostics and tests on the various modules and instrument cluster and there are no issues reported. I don't have control to do manual tests like the official diagnostic equipment.
I did pull the ambient sensor and the pin that outputs the signal shows ~8 volts or 0 volts depending on dark or light. I obtained a second/used sensor and it does the same. Not sure if this is correct because the signal is going over the SCP network and I know, for example, the light switch just uses different resistances (voltages) over the same pin to tell the IC/FEM what to do (off, park, headlights,)

I have a 2012 Fusion and it will cycle as many times as the ambient lighting conditions change.

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Uh - that doesn't sound right; I have my '02's dash ripped apart right now so I can't confirm but I recall driving the car in AUTO headlamps and I would go under 3-4 overpasses at times and IIRC the lights came in the darkness of the overpass and then turned off once I exited... Besides, just on the face of it, the operation you're describing makes no sense as a normal operational feature.

Anyway, reading the operation part of exterior lighting it says:
The autolamps are controlled by the headlamp switch, autolamp sensor (also referred to as the photocell and amplifier), instrument cluster and the FEM. The headlamps may be in the high or low beam position depending on the multifunction switch position. When the headlamp switch is in the autolamp position, the instrument cluster will send an ON or OFF command to the FEM, depending on the signal from the autolamp sensor. The FEM will process this information and output the appropriate command to the headlamps, which are hardwired to the FEM. The autolamps will remain ON for approximately 20 seconds after the ignition switch is changed from the RUN position to the ACC or OFF position.

To wit, you have two of the flakiest electrical components involved in this feature, the Instrument Cluster and the FEM (I am currently dealing with an ugly gauge lighting issue involving both)... The "pinpoint" tests seem to indicate the Instrument Cluster but a Ford dealer can diagnose the issue (I had this done for my problem about $130)..

It'll suck if its the Instrument Cluster as the FEM is a much simpler part to deal. The cluster holds the mileage and the dealers don't want to fiddle with anything under Federal regs...been there, done that.
When you say the lights based on ambient light will not turn off, I'm trying to understand what you are saying, if the lights go off due to daylight then come back on again due to lack of daylight then again come on due to ambient light change THAT once this occurs they will not go off again? They remain on? Do they ever go off, like when you shut down the engine & open the door? Depending on how far the auto setting is turned will lengthen the 'on time' of the lights.

This even occurs when driving. For instance car is started in a darken garage, pull out into bright sun light. Lights will remain on until they clock out. They do not immediately shut off as soon as the sensor sees (senses) sun light. Now lets say you enter a tunnel, the sensor no longer sees daylight the lights will come on and as you exit the tunnel they do not turn off until the sensor sees bright daylight & they clock out. It is instant on but not instant off.

This is the way my 05 functions. If an 02 functions differently hopefully an 02 owner will jump in here and help clarify all of this.
To all who have replied.
1) no other issues or symptoms with lighting, IC etc that would indicate the FEM (or IC) is bad. Just this unusual autolamp operation
2) Once the sensor has turned on the headlights for the second time (due to darkness), they will not automatically shut off once the sensor is exposed to daylight again.
3) they will shut off by turning the headlight switch to off. (normal/expected operation) but if key has not been turned off, turning the switch back to autolamp causes the headlights to turn on, even if daytime.
4) Under all circumstances/scenarios: With autolamp switch on, headlight delay and shut off work fine when the key is turned off (this is normal/expected operation). This is true even if the headlights were "stuck" on.
5) Turning the key off and back on causes correct autolamp operation but only for the 1.5 cycles (i.e. light sensor on-off-on cycle), then the lights are stuck on when in autolamp mode until key off.
6) The sensor output is either ~0 volts or~8 volts depending on ambient light conditions.

If autolamp didn't work at all or headlights always on in autolamp mode diagnosis would be easier. Also hoping Frankie has time to check the voltage on the sensor output pin. As I mentioned I have two used sensors now and both output 0/8 volts. I've since found a place with NOS sensors but am hesitant to buy. Is the IC/FEM simply responding to certain voltage levels or is there some kind of "computer" signal embedded in it? I beleive it is just different voltage levels because of the wiring schematic for the main headlight switch. It just uses different resistance depending on where the switch is at, to vary voltage on the switch output pin. I've done the service manual pinpoint tests on the switch and all seems good there.

I've been reading in my 05 shop manual & I doubt there is much difference between the 02 & 05 in the lighting circuitry. The book has a paragraph that mentions that if a problem is detected with the headlamp switch signal circuit(8LE21) or the headlamp switch signal return circuit (9-LE29) or the headlamp switch itself the instrument cluster will default the headlamps and parking lamps ON. This is mentioned under the bold print of TEST A and again at TEST E of both headlamps. This makes a the headlamp switch a possible cause of your problem.

Then I found that it is the instrument cluster(IC) that receives the data from the ambient sensor and then & then it the IC signals the front electronic module(FEM) & the rear electronics module(REM) to turn the headlights & taillights on. The FEM turns on the headlights only, the REM turns on the tail lights only. This in a way may help zero in a bit, from my way of thinking if the tail lights are operating correctly while the headlights are not then it would seam that the IC is okay and the FEM is the problem. If both the headlights & the tail lights are doing the same than this points at the IC.

Also in the battery junction there is 4 relays. SSP 1 & SSP 2 are in the lighting circuits. #1 when switched on by ignitions switch ON provides the source power to all of this by way of the circuitry going thru the central junction box pass. foot well.

I am very interested in this problem & would appreciate you keeping us updated on what you find.
I have a 2003 and when in the auto mode the lights come on when I start the car (Daytime or night time) and depending where I set the amount of delay turn off, when I turn off the car the lights turn off. After all that I am reading I guess this feature has a mind of its own and works differently car to car.

Have not been able to spend more time on this "feature" but am hoping someone with an 02 can see how their autolamps cycle during a short period of time, or if Frankie was ever able to measure the output of the ambient light sensor?

My 02 auto lamp feature is on as well regardless of day or night. I have a replacement sensor but have not taken the dashboard apart to replace it yet. Hope to do it soon now that the temperature here in Southern Arizona is starting to cool down.

Have an 02 and my autolamps work fine. I keep autolamp on all
the time. When I start car lamps come on, when I pull out of garage
during day lamps turn off after about 30 seconds of sunlight.

When I pull into garage lights turn on when I turn car off, and stay on for
about 10 or 15 seconds, then turn off.
I have a 03 and they work the same as above. When in the auto mode the lights turn on either in daylight or night time. The fog lights also go on and the switch seems to have no effect on them, they are in sinc with the lights. I can control the time the lights turn off when I turn off the car. I think the next time I bring it in for oil change and inspection I will have them check it out. I also found out that Ford makes changes during the year so my 03 can have a totally different configuration then another 03. That is why they always ask for the Ser #. No matter what the Thinderbirds are the best of the best.
I have a 03 and they work the same as above. When in the auto mode the lights turn on either in daylight or night time. The fog lights also go on and the switch seems to have no effect on them, they are in sinc with the lights. I can control the time the lights turn off when I turn off the car. I think the next time I bring it in for oil change and inspection I will have them check it out. I also found out that Ford makes changes during the year so my 03 can have a totally different configuration then another 03. That is why they always ask for the Ser #. No matter what the Thinderbirds are the best of the best.
You have nothing to be checked out. Everything is functioning normally. The pullout light switch serves no purpose. BTW, those are not fog lights. They are supplemental parking lights meant to come on with the parking and/or headlights.
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Group, thanks for your input. I do agree my symptoms don't seem right. BluBye U provides some interesting info about the IC permanently turning on lights if it senses a problem. I may re-diagnose my switch. I don't know that the IC is able to separately tell the FEM or REM to turn lights on/off. I think the same IC signal goes to both modules. It seems some may not quite understand my symptoms. When in autolamp mode, during the same "driving cycle" (i.e. no key off) the lights will turn on up to two times based on whether I've blocked or not blocked the sensor. After they turn on for the 2nd time they will not turn off unless 1) turn off the headlights using the switch 2) turn off the car. Under scenario 1, turning the lights back to autolamp mode turns them on even if it is daytime and the sensor is saying "it's daytime". Under scenario 2, if still in autolamp mode, the delay feature works just fine. Upon next use of car Autolamp feature will again work as above. So turning the car off is "resetting" something but that something still only allows for on-off-on of the lights during one driving cycle.
P.S. to Steve F. For 02 it's pretty easy. You only need to remove the defroster grill panel. Before you do that you need to remove the "A" pillar trim panels. No screws in the panels, just those terrible metal clips. Try to figure out the general location(s) of the clips and pull/pry as close as possible to those locations. Be careful with the grill. The wire harness leading to the sunload sensor and the ambient light sensor is short. Just get the grill mostly detached and you'll see the harness coming in from the passenger side. Assuming the sensor is the problem you should be able to replace without detaching everything even though it's a little cramped.