LED resistor question
Race Director
Joined: Oct 2007
Posts: 11,367
Likes: 211
From: Edgewood Washington
St. Jude Donor '11-'12-'13-'14-'15
Wrong.
When you think you have the DRL circuit turned on, you actually have turned on the running/parking lamp circuit that share the same light fixture as the DRL.
"DRL's on solid with headlights on = no current to either resistor" is a dead giveaway. When the headlights are on, the running light circuit is on, not the DRL circuit. Weren't your side markers on too? Another giveaway.
The DRL's and the turn signals share the same socket connector pin, wire, and brighter side of the bulb. There's only 2 hot wires in the connector (plus a ground).
Remember, for the DRL's to be on, the car must be on, it must be daylight, the stalk switch must be in auto, and an A6 trans. must be in gear (with the manual trans I think you just need to have the parking brake off).
Try this test: turn on your headlights. The running lights are on too, look at the side markers. Then turn on your turn signals and watch how the amber light flashes from dim to bright. The bright light is the one used for the DRL's.
The DRL's are not the light in the cluster. DRL's are a circuit/function that uses the same light fixture as the turn signals and running/parking lights.
I don't know how I can make this any clearer.
Good Luck
When you think you have the DRL circuit turned on, you actually have turned on the running/parking lamp circuit that share the same light fixture as the DRL.
"DRL's on solid with headlights on = no current to either resistor" is a dead giveaway. When the headlights are on, the running light circuit is on, not the DRL circuit. Weren't your side markers on too? Another giveaway.
The DRL's and the turn signals share the same socket connector pin, wire, and brighter side of the bulb. There's only 2 hot wires in the connector (plus a ground).
Remember, for the DRL's to be on, the car must be on, it must be daylight, the stalk switch must be in auto, and an A6 trans. must be in gear (with the manual trans I think you just need to have the parking brake off).
Try this test: turn on your headlights. The running lights are on too, look at the side markers. Then turn on your turn signals and watch how the amber light flashes from dim to bright. The bright light is the one used for the DRL's.
The DRL's are not the light in the cluster. DRL's are a circuit/function that uses the same light fixture as the turn signals and running/parking lights.
I don't know how I can make this any clearer.
Good Luck
Burning Brakes
Joined: May 2008
Posts: 752
Likes: 28
From: Ottawa, Ontario
Wrong.
When you think you have the DRL circuit turned on, you actually have turned on the running/parking lamp circuit that share the same light fixture as the DRL.
"DRL's on solid with headlights on = no current to either resistor" is a dead giveaway. When the headlights are on, the running light circuit is on, not the DRL circuit. Weren't your side markers on too? Another giveaway.
The DRL's and the turn signals share the same socket connector pin, wire, and brighter side of the bulb. There's only 2 hot wires in the connector (plus a ground).
Remember, for the DRL's to be on, the car must be on, it must be daylight, the stalk switch must be in auto, and an A6 trans. must be in gear (with the manual trans I think you just need to have the parking brake off).
Try this test: turn on your headlights. The running lights are on too, look at the side markers. Then turn on your turn signals and watch how the amber light flashes from dim to bright. The bright light is the one used for the DRL's.
The DRL's are not the light in the cluster. DRL's are a circuit/function that uses the same light fixture as the turn signals and running/parking lights.
I don't know how I can make this any clearer.
Good Luck
When you think you have the DRL circuit turned on, you actually have turned on the running/parking lamp circuit that share the same light fixture as the DRL.
"DRL's on solid with headlights on = no current to either resistor" is a dead giveaway. When the headlights are on, the running light circuit is on, not the DRL circuit. Weren't your side markers on too? Another giveaway.
The DRL's and the turn signals share the same socket connector pin, wire, and brighter side of the bulb. There's only 2 hot wires in the connector (plus a ground).
Remember, for the DRL's to be on, the car must be on, it must be daylight, the stalk switch must be in auto, and an A6 trans. must be in gear (with the manual trans I think you just need to have the parking brake off).
Try this test: turn on your headlights. The running lights are on too, look at the side markers. Then turn on your turn signals and watch how the amber light flashes from dim to bright. The bright light is the one used for the DRL's.
The DRL's are not the light in the cluster. DRL's are a circuit/function that uses the same light fixture as the turn signals and running/parking lights.
I don't know how I can make this any clearer.
Good Luck
The point here is that the DRLs (turning on and off) are controlled 100% by the BCM and NOT the light switch on the turn signal stalk.
BTW, like you I'm unsure exactly what you have to do with a manual transmission car to get the DRLs to come on. In addition you may actually have to have the car in gear.
But hey, it's his car, and he'll have to deal with the consequences. Just hoping it doesn't burn!! Those resistors run in the 300-400 deg range.
Thread Starter
Melting Slicks
Joined: Aug 2002
Posts: 2,193
Likes: 195
From: New Caney Texas
Not sure how you can come to the conclusion that I'm "confused" about how the DRL's work when my results are based on a real-world implementation. Do either of you currently have or have previously installed LED DRL's and resistors in C6's or are you serving up your "experience" second-hand?
The scenarios results I detailed above are irrefutable and not up for interpretation however they were performed with the motor running, the car parked with MT in neutral and the emergency brake engaged.
If it your assertion that the "bright" filament of the two circuits going to the parking/running light socket is hot while the car is in gear but not while parked then that is a scenario I have not validated yet however that will can be resolved this weekend.
The scenarios results I detailed above are irrefutable and not up for interpretation however they were performed with the motor running, the car parked with MT in neutral and the emergency brake engaged.
If it your assertion that the "bright" filament of the two circuits going to the parking/running light socket is hot while the car is in gear but not while parked then that is a scenario I have not validated yet however that will can be resolved this weekend.
Drifting
Joined: Aug 2012
Posts: 1,587
Likes: 5
From: central NJ
RC, you just stated that the emergency brake is engaged!! Thats the problem. When the e-brake is engaged the DRL is not in effect. Take the brake off and in neutral and the resistors will get hot.... I made the same mistake with my A6, i didnt put it in drive and the resistors stayed stone cold. Went for a ride the next day, opened the hood and touched the resistor thinking it was cold because i didn't use my turn signals and now i have a tattoo that says 50w6(ohm)J on my palm.... (just kidding about that last part, but it was hot!!)
Burning Brakes
Joined: May 2008
Posts: 752
Likes: 28
From: Ottawa, Ontario
Not sure how you can come to the conclusion that I'm "confused" about how the DRL's work when my results are based on a real-world implementation. Do either of you currently have or have previously installed LED DRL's and resistors in C6's or are you serving up your "experience" second-hand?
The scenarios results I detailed above are irrefutable and not up for interpretation however they were performed with the motor running, the car parked with MT in neutral and the emergency brake engaged.
If it your assertion that the "bright" filament of the two circuits going to the parking/running light socket is hot while the car is in gear but not while parked then that is a scenario I have not validated yet however that will can be resolved this weekend.
The scenarios results I detailed above are irrefutable and not up for interpretation however they were performed with the motor running, the car parked with MT in neutral and the emergency brake engaged.
If it your assertion that the "bright" filament of the two circuits going to the parking/running light socket is hot while the car is in gear but not while parked then that is a scenario I have not validated yet however that will can be resolved this weekend.
1) My mechanic (who is extremely competent) tried to install the LEDs with resistors in my car and gave up as the LEDs would not function properly. They would light up white, but not flash. He also installed the resistors and commented about how hot they got. We we both uncomfortable with that.
2) I tried to install them myself, but could not get the LEDs to function properly. See above.This involved looking at the wiring and the bulb socket.
3) A very thorough examination of the factory wiring schematics (in the FSM....you know the bible) to determine how the parking lights, turn signals and DRLs actually work. Have you looked at the wiring schematics?
As has already been noted, you had the parking brake on, which means that the DRLs will NOT come on.
I'm done with this thread.
Safety Car
Joined: Sep 2006
Posts: 4,075
Likes: 6
From: Wilmington NC
That's why I decided not to comment on the latest "I know what I'm doing and your all wrong" scenario. As the saying goes, you can lead a horse to water........
Last edited by j_digi454; Jan 24, 2013 at 01:10 PM.
Thread Starter
Melting Slicks
Joined: Aug 2002
Posts: 2,193
Likes: 195
From: New Caney Texas
My comments are based on three things:
1) My mechanic (who is extremely competent) tried to install the LEDs with resistors in my car and gave up as the LEDs would not function properly. They would light up white, but not flash. He also installed the resistors and commented about how hot they got. We we both uncomfortable with that.
2) I tried to install them myself, but could not get the LEDs to function properly. See above.This involved looking at the wiring and the bulb socket.
3) A very thorough examination of the factory wiring schematics (in the FSM....you know the bible) to determine how the parking lights, turn signals and DRLs actually work. Have you looked at the wiring schematics?
As has already been noted, you had the parking brake on, which means that the DRLs will NOT come on.
I'm done with this thread.
1) My mechanic (who is extremely competent) tried to install the LEDs with resistors in my car and gave up as the LEDs would not function properly. They would light up white, but not flash. He also installed the resistors and commented about how hot they got. We we both uncomfortable with that.
2) I tried to install them myself, but could not get the LEDs to function properly. See above.This involved looking at the wiring and the bulb socket.
3) A very thorough examination of the factory wiring schematics (in the FSM....you know the bible) to determine how the parking lights, turn signals and DRLs actually work. Have you looked at the wiring schematics?
As has already been noted, you had the parking brake on, which means that the DRLs will NOT come on.
I'm done with this thread.
Regardless, thanks for that clarification.
I've already indicated I will rerun the different light-up and resistor temp scenarios with both the emergency brake disengage and the car in gear this weekend. While some people have no issue quoting advice based on hearsay or 2nd hand knowledge I prefer to base my statements on on real-world proof.
Last edited by RC4G; Jan 24, 2013 at 01:43 PM.
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Thread Starter
Melting Slicks
Joined: Aug 2002
Posts: 2,193
Likes: 195
From: New Caney Texas
RC, you just stated that the emergency brake is engaged!! Thats the problem. When the e-brake is engaged the DRL is not in effect. Take the brake off and in neutral and the resistors will get hot.... I made the same mistake with my A6, i didnt put it in drive and the resistors stayed stone cold. Went for a ride the next day, opened the hood and touched the resistor thinking it was cold because i didn't use my turn signals and now i have a tattoo that says 50w6(ohm)J on my palm.... (just kidding about that last part, but it was hot!!)
I intent to run additional tests this weekend and will confirm if the resistors receive current dependant on the car being in gear and/or the emergency brake applied.
Drifting
Joined: Aug 2012
Posts: 1,587
Likes: 5
From: central NJ
Take e-brake off, resistors SHOULD get hot (i have an A6 so i'm taking peoples word on this.)
Drive around for 20-30 minutes and DON'T USE TURN SIGNALS at all and when you get home i guarantee you they will be 300-400 degrees!!! That i am positive on because thats how they work if installed properly and thats how i got burned....
PS *MAKE SURE LIGHTS ARE ON AUTO*
Melting Slicks
Joined: Oct 1999
Posts: 2,181
Likes: 421
From: Ponte Vedra Beach FL
Thread Starter
Melting Slicks
Joined: Aug 2002
Posts: 2,193
Likes: 195
From: New Caney Texas
Its become apparent that different individual's installation (as well as failed install attempts) have produced different results. Even the input in this thread shows that people are not certain what factors control the two circuits: some say its tied to emergency brake, other says it has to be in gear.
With about 10 more minutes of testing I will be able to definitively define when/how the "bright" circuit on that socket gets voltage for a MT C6, plain and simple.
As for mounting the resistors I will intentionally be isolating the mount as to minimize heat transferrance between the resistor and the mount point. Right now the 3M Moulding Tape utilized seems to be holding up very well to the high heat of the resistor without transferring that heat to where it is mounted on the front support next to what I believe are the headlight ballasts. The resistor is already designed to dissapate heat at the rated wattage and should not require any additional convection cooling associated by mounting directly to a metal surface.
Last edited by RC4G; Jan 24, 2013 at 04:54 PM.
Thread Starter
Melting Slicks
Joined: Aug 2002
Posts: 2,193
Likes: 195
From: New Caney Texas
Interesting stance considering that if others had taken the same approach (eschewing real-world testing and documentation to try and solve a problem) with the RC51 then you would still be banging away on Honda's soft rev limiter.
The reality is I don't post other people's experiences or general 2nd hand knowledge as my own. The amount of time required to document this is negligible in the scheme of things and has the benefit of helping others so there is no reason not do it.
The reality is I don't post other people's experiences or general 2nd hand knowledge as my own. The amount of time required to document this is negligible in the scheme of things and has the benefit of helping others so there is no reason not do it.
Last edited by RC4G; Jan 24, 2013 at 04:53 PM.
Race Director
Joined: Oct 2007
Posts: 11,367
Likes: 211
From: Edgewood Washington
St. Jude Donor '11-'12-'13-'14-'15
The easiest way to confirm you are in DRL mode is when the front turn signals are on steady, and no other exterior lights are on.
Here are some pics of how I mounted my load resistors.
They have the typical integrated finned aluminum heat-sink and they are bolted to an additional heat-sink/mounting plate (pic 1) that has an air gap underneath to improve cooling (pic 2).
Then the load resistors/etc. are mounted to a canvas phenolic panel providing total isolation from the mounting surface of the car. (pic 3).
I know this is overkill, but I had the pieces/parts available and it makes for an easily-serviced install.
Here are some pics of how I mounted my load resistors.
They have the typical integrated finned aluminum heat-sink and they are bolted to an additional heat-sink/mounting plate (pic 1) that has an air gap underneath to improve cooling (pic 2).
Then the load resistors/etc. are mounted to a canvas phenolic panel providing total isolation from the mounting surface of the car. (pic 3).
I know this is overkill, but I had the pieces/parts available and it makes for an easily-serviced install.
Race Director
Joined: Oct 2010
Posts: 14,475
Likes: 785
From: Las Vegas NV
The easiest way to confirm you are in DRL mode is when the front turn signals are on steady, and no other exterior lights are on.
Here are some pics of how I mounted my load resistors.
They have the typical integrated finned aluminum heat-sink and they are bolted to an additional heat-sink/mounting plate (pic 1) that has an air gap underneath to improve cooling (pic 2).
Then the load resistors/etc. are mounted to a canvas phenolic panel providing total isolation from the mounting surface of the car. (pic 3).
I know this is overkill, but I had the pieces/parts available and it makes for an easily-serviced install.
Here are some pics of how I mounted my load resistors.
They have the typical integrated finned aluminum heat-sink and they are bolted to an additional heat-sink/mounting plate (pic 1) that has an air gap underneath to improve cooling (pic 2).
Then the load resistors/etc. are mounted to a canvas phenolic panel providing total isolation from the mounting surface of the car. (pic 3).
I know this is overkill, but I had the pieces/parts available and it makes for an easily-serviced install.
Melting Slicks
Joined: Oct 1999
Posts: 2,181
Likes: 421
From: Ponte Vedra Beach FL
Interesting stance considering that if others had taken the same approach (eschewing real-world testing and documentation to try and solve a problem) with the RC51 then you would still be banging away on Honda's soft rev limiter.
The reality is I don't post other people's experiences or general 2nd hand knowledge as my own. The amount of time required to document this is negligible in the scheme of things and has the benefit of helping others so there is no reason not do it.
The reality is I don't post other people's experiences or general 2nd hand knowledge as my own. The amount of time required to document this is negligible in the scheme of things and has the benefit of helping others so there is no reason not do it.
And I have installed the LED DRLs (not the unimpressive switchback model, just the plain white. Why be yellow?) and when my car was in my brightly-lit garage during initial testing...and I guess I had the headlights in Auto...those resistors were hot as fooooking blazes when the DRLs were on. So, regardless of whatever the foooking electronics and electrics and which of the three wires someone may or may not have tapped in to (and I used the correct Blue/White wire), my resistors were so foooking hot I suspended them by safety wire (useful for 90* V-Twin bikes that rev to 10500!
) and went on with my life. So, my system works fine. I'll let you guys battle it out and melt holes in your plastic panels....
NOTE: I had two...repeat TWO...white DRLs from our friend Neal at CvetteMods that did not work, in that they "turn signaled" but didn't do the DRL thing. That was very confusing, as you can imagine. But good ol' Neal made good on the problem in a jiffy and now I have a very nice, fully white front lighting array (low beam upgrade, fog HID upgrade).
Team Owner
Joined: Dec 2002
Posts: 32,074
Likes: 296
From: San Francisco CA
OK, after reading all of the comments I've no choice but come to the conclusion that some of the people who posted in this thread fall into one or both of the following two categories:
A Have zero personal experience installing DRL's and resistors on a C6.
B Have no basic understanding of how a dual filament turn signal / running light bulb works.
I can tell you that the following observations are the result of my installation and I re-verified the various scenarios this morning to confirm. I tested the scenarios with no turn signal first for obvious reasons.
My results of a successful DRL/resistor installation on a C6 Corvette are as follows:
1. All lights off (DRL's, markers, headlights, etc) = no current to either resistor
2. DRL's on solid with headlights off = no current to either resistor
3. DRL's on solid with headlights on = no current to either resistor
4. DRL's on solid with headlights off and turn signals activated = intermittent current to one resistor
5. DRL's on solid with headlights on and turn signals activated = intermittent current to one resistor
Additionally as you can see from the attached video there is no hyperflash and I can confrim that the resistors are working as designed when the turn signals are activated as they get warm to the touch quickly.
As I stated previously, when correctly installed the resistors only receive current when the turn signals are activated. Anyone who claims otherwise has either never actually performed the installation themselves or tapped the wrong hot lead on the DRL bulb socket harness that leads to one side of for the resistor (the other side of the resistor goes to ground obviously).
A Have zero personal experience installing DRL's and resistors on a C6.
B Have no basic understanding of how a dual filament turn signal / running light bulb works.
I can tell you that the following observations are the result of my installation and I re-verified the various scenarios this morning to confirm. I tested the scenarios with no turn signal first for obvious reasons.
My results of a successful DRL/resistor installation on a C6 Corvette are as follows:
1. All lights off (DRL's, markers, headlights, etc) = no current to either resistor
2. DRL's on solid with headlights off = no current to either resistor
3. DRL's on solid with headlights on = no current to either resistor
4. DRL's on solid with headlights off and turn signals activated = intermittent current to one resistor
5. DRL's on solid with headlights on and turn signals activated = intermittent current to one resistor
Additionally as you can see from the attached video there is no hyperflash and I can confrim that the resistors are working as designed when the turn signals are activated as they get warm to the touch quickly.
As I stated previously, when correctly installed the resistors only receive current when the turn signals are activated. Anyone who claims otherwise has either never actually performed the installation themselves or tapped the wrong hot lead on the DRL bulb socket harness that leads to one side of for the resistor (the other side of the resistor goes to ground obviously).
