and the year might have something to do 
Twilight Sentinel
Thread Starter
Burning Brakes
Joined: Nov 2013
Posts: 1,036
Likes: 119
Twilight Sentinel
My car is equipped with twilight sentinel, but it's never worked right. The headlights just stay up and on constantly. I've been busy fixing bigger and more important issues for a while, so I just pulled the fuse and operate the headlights manually. I can't seem to disable it through the DIC. For now it works fine. I'd like to fix this though.
I believe my issue is the light sensor. It seems to be missing from the vent area by the windshield. I removed the vent and looked in with a flashlight, and I don't see any suspicious wires or sensors hanging loose like they fell in. Anyone have any suggestions or pictures of what I should be looking for?
I believe my issue is the light sensor. It seems to be missing from the vent area by the windshield. I removed the vent and looked in with a flashlight, and I don't see any suspicious wires or sensors hanging loose like they fell in. Anyone have any suggestions or pictures of what I should be looking for?
Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
It should be obvious at the vent on the drivers side. If it is down in the dash that would explain why it "thinks" it is dark. Not sure why you can't disable it thru the DIC unless you are saving the change, but I really doubt that is the reason.
Pull your DIC codes and see if that shows anything.
I will research some more when I get home later. Have not looked at that circuit in a long time. There is a way to disable it without using the DIC, but that is just a bandaid and not a real fix.
Pull your DIC codes and see if that shows anything.
I will research some more when I get home later. Have not looked at that circuit in a long time. There is a way to disable it without using the DIC, but that is just a bandaid and not a real fix.
Thread Starter
Burning Brakes
Joined: Nov 2013
Posts: 1,036
Likes: 119
It should be obvious at the vent on the drivers side. If it is down in the dash that would explain why it "thinks" it is dark. Not sure why you can't disable it thru the DIC unless you are saving the change, but I really doubt that is the reason.
Pull your DIC codes and see if that shows anything.
I will research some more when I get home later. Have not looked at that circuit in a long time. There is a way to disable it without using the DIC, but that is just a bandaid and not a real fix.
Pull your DIC codes and see if that shows anything.
I will research some more when I get home later. Have not looked at that circuit in a long time. There is a way to disable it without using the DIC, but that is just a bandaid and not a real fix.
Thread Starter
Burning Brakes
Joined: Nov 2013
Posts: 1,036
Likes: 119
Yeah, I get the the Twilight sentinel option on the DIC and it is stuck on the ON setting. Reset doesn't change it. I know the reset button works in other areas of the DIC, so it's not a bum button.
Would there be a relay for Twilight sentinel if the option didn't originally exist? Removing said relay has allowed me to operate my lights manually, so it's certainly doing something.
Would there be a relay for Twilight sentinel if the option didn't originally exist? Removing said relay has allowed me to operate my lights manually, so it's certainly doing something.
Melting Slicks
Joined: Jul 2005
Posts: 2,990
Likes: 346
From: Mt. Pleasant S.C.
You can program it out of BCM with a TechII, or get the sensor (it's cheap) and drop it in. The wire that plugs into the censor should be taped to the side of your steering column. Should be a yellow piece of tape if I remember right.
Instructions (and part number) here http://www.stopforce.com/RPO.html
Instructions (and part number) here http://www.stopforce.com/RPO.html
Team Owner
Joined: Jul 2006
Posts: 22,141
Likes: 4,156
From: Kannapolis NC
Canadian export cars don't have the option to disable twilight sentinel. Nothing in your profile, nothing in your question about location, but it could still be an export car. Check the RPO codes.
Melting Slicks
Joined: Jul 2008
Posts: 2,889
Likes: 25
From: CALIFORNIA
Thread Starter
Burning Brakes
Joined: Nov 2013
Posts: 1,036
Likes: 119
I'm in Indiana, when I did a carfax before I bought it, I believe it was first registered and lived out its life in Ohio. I'm trying to get into my carfax account to double check, but for some reason my login is failing.
Also, the car is a 99.
Also, the car is a 99.
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Melting Slicks
Joined: Jul 2013
Posts: 2,012
Likes: 23
From: Anaheim CA
When you pull it up in the DIC it should say either ON or OFF. Reset button toggles it.
Of course it is also possible that the BCM in the car was replaced at some time in its life and an RPO that did not exist on the actual car was programmed into the BCM. Since you do not have the sensor, that would make some sense.
Of course it is also possible that the BCM in the car was replaced at some time in its life and an RPO that did not exist on the actual car was programmed into the BCM. Since you do not have the sensor, that would make some sense.
Somebody probably pulled the dash at some point and "lost" the sensor.
Melting Slicks
Joined: Jul 2013
Posts: 2,012
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From: Anaheim CA
Thread Starter
Burning Brakes
Joined: Nov 2013
Posts: 1,036
Likes: 119
I have seen some signs that the dash was removed before as I've been fixing things. Perhaps that is the case. I'll give it another look under the vent this weekend and see what I find.
Melting Slicks
Joined: Sep 2011
Posts: 2,258
Likes: 543
From: Appleton WI
The sensor may have fallen out of the grill and is laying somewhere in the dash. The wires feed from the drivers side. Should be a two wire lead IIRC.
Melting Slicks
Joined: Jul 2005
Posts: 2,990
Likes: 346
From: Mt. Pleasant S.C.
I disagree. My Z06 didn't have the sensor and the DRL worked fine. I bought the sensor, untaped the wires from the steering column to feed up to the dash grill, and had a someone activate the feature in the computer. Now my system works just like a coupe / vert and I can turn on / off twilight sentinal
This ^^^^
Racer
Joined: Nov 2005
Posts: 457
Likes: 0
From: Rockville MD
Sounds like your BCM might be out of a Canadian model, or somehow the options was shut off in the BCM.
I had the same issue recently, I had a different RPO code tuned out of my car with a tech-II, once that was completed my lights would come on automatically, and I could not disable the twilight sentinel option from the DIC (pressing reset did nothing)
We had to go back into the BCM menu with the Tech-II and make sure the US option was selected, after that I was once again able to disable the twilight sentinel option from the DIC.
I had the same issue recently, I had a different RPO code tuned out of my car with a tech-II, once that was completed my lights would come on automatically, and I could not disable the twilight sentinel option from the DIC (pressing reset did nothing)
We had to go back into the BCM menu with the Tech-II and make sure the US option was selected, after that I was once again able to disable the twilight sentinel option from the DIC.
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Thread Starter
Burning Brakes
Joined: Nov 2013
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I'm ok with twilight sentinel, don't really need to disable it if it would work. I'm betting I'm just missing the sensor or it's tucked back somewhere. How do I access the harness on the steering column? Do I have to remove any panels or can I access it from below?
Melting Slicks
Joined: Jul 2013
Posts: 2,012
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From: Anaheim CA
Might be a year-dependent thing, but the description in my '04 FSM says (in part): "The DRL operates when the ignition switch is in the RUN position, and the parking brake is not set or the transmission is not in park. When these conditions have been met and the ambient light sensor indicates daytime conditions, the DRL will illuminate."
Racer
Joined: Nov 2005
Posts: 457
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From: Rockville MD
Can you currently toggle twilight sentinel on/off from the DIC? If not it might be the RPO issue that a few of us have mentioned. But definitely check to see if the sensor is in place.
Last edited by vettestream; Jun 13, 2014 at 04:37 PM.
Melting Slicks
Joined: Jul 2013
Posts: 2,012
Likes: 23
From: Anaheim CA
Unless you can see the existing sensor or wire through the defroster opening and fish it out, the dash will almost certainly need to come off.