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ambient light sensor


alero99
11-29-2006, 10:04 PM
Does anyone know where the ambient light sensor is and how to gain access to it on a 99 alero? I looked it up on a Mitchell OnDemand and all it said was on top of the dash pad. That doesn't really tell me much though. Ive looked all over up there before and don't see anything.

xeroinfinity
11-29-2006, 10:23 PM
it is under the defrost panel.

You cant see it unless you look from outside through the windshield.

Thier is a thread on disabling your Day time running lights (http://www.automotiveforums.com/vbulletin/showthread.php?t=595762)(DRL's) and has some info with pics.

alero99
12-01-2006, 11:33 PM
you almost read my mind...what im looking to do is put a switch on the ambient so the automatic lights still work but i can turn off my headlights when i want to. Since im color blind i figure itd be a lot easier to splice in the switch when i see the two wires going into the als then sort through the mess of wires on the bcm.
Do i have to take off the dash pad or the radio to get to it or is there an easier way?

xeroinfinity
12-02-2006, 07:46 AM
Everything is taped up pretty good inside the dash area.

The easiest way to get in and look is through the glove box.
- 5 screws hold it in, dont forget the light thats pluged in on the glovebox, it just unplugs.
Once thats out, you can see the BCM below and the pass air bag(stay away from that death trap:grinyes:)
You might be able to get to the ALS two wires from below.

Switching can be dangerous if it was do with the key on.
Might damage the Bcm.
To disable the ALS, the two wires on the BCM side should be connected to close the circuit, so it thinks its daylight all the time.

At connector C2 , find A3 the yellow/black wire, and B2 light green/black wire
! Be careful because there are two light green/black wires on that connector, the one you want is closest to the yellow/black wire.

Cut these wires again leaving as much wire as possible attached to the BCM. Simply tie the two wires together (I used a electrical wire cap) and then taped it up real good. This would be the same thing as removing ambient light sensor and adding a jumper wire.


IMO , If you cant see the wire colors then maybe you should not mess with them, get someone to help you locate the correct wires.

Good Luck

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