Will resistors restore my cruise control with LED brake lights?
#41
That makes sense. Now that I have the cruise working again I'm interested in changing the turn signals and DRL's to LED. When I changed my front turn signal housings back to stock I noticed the DRL"s had melted the housings. I'm guessing that the lower heat output of the LED's would prevent that from happening again.
#42
Get new bulb sockets from Auto zone et al, and disassemble them as well as the old burnt ones being careful not to ruin your existing wires. You can then slip your old wire ends into the new sockets and done! Did the same to my '02 and added LED turn signals.
#44
My blinker sockets were burnt and brittle; common problem using incandescent bulbs.
I also changed out my blinker to one with a pigtail.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
I also changed out my blinker to one with a pigtail.
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
#45
Old thread I know but this may help others. The TAC module connects to the brake circuit with a single wire so it cannot sense current it is measuring voltage. It simply needs to know if the pedal is depressed. The diodes can act as tiny capacitors storing a very small charge this is why some leds stay dimly lit for a while after use. If the module detects any voltage it will disable the circuit. A small resistor across the center light contacts Would give the stored charge a path to ground. (Pull down resistor) This solved my ghost light problem and will likely fix the cruise in this situation too. Use the largest value resistor that works. The TAC module is looking for a yes or no what it's getting is yes and maybe which it sees as a yes also. A pull down resistor near the module would be best imo. This could also be fixed with a relay though a bit more complicated.
#46
TECH Addict
iTrader: (30)
i actually just tapped my stock Z28 3rd brake light wires into my SS spoiler LED bar and ran the wires down the sail panel and into my spare tire compartment. This added enough resistance to the system to allow my cruise to work with no ill effect on my LED's. Everything works great now
The following users liked this post:
ramairjohn2000 (07-07-2020)
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wannafbody (05-25-2021)
#48
ok so i know this is a bit of an old thread, but i've got a decisive answer (I've fixed this very same issue just now).
Just to be clear - my issue was that after I installed LED tail lights (Anzo, if you were curious), my cruise control stopped working. Turn signals were a-okay, it was just the cruise that was messed up. After a lot of Googling, I quickly figured out that putting in a resistor of some sort somewhere would fix the problem...didn't get any real clear answers, but I figured it out - so here it is!
I got a couple 25W 6ohm resistors from autozone (they have a little kit specifically for this purpose - look in the light bulb section). The kit comes with 4 wire taps, as well. You don't have to cut any wires or anything, it's very easy.
- Pull the carpet back in the trunk, exposing the wires on the driver's side.
- Pull back the electrical tape on the bunch of wires there, and find a light blue one, and a black one. You will see the black one goes directly to a bolt in the center of the trunk for a body ground.
- Using the wire taps, connect the light blue with the black ground wire with the resistor. Be sure to leave yourself a good bit of wire to make it easy to mount the resistors somewhere safe (more on that later). I bought a coil of 18 gauge wire for this purpose, as well as a few more wire taps.
- Mount the resistor somewhere safe using steel zip ties (plastic might melt, those things ger really freaking hot. I mounted mine in the middle of the trunk by the latch, on the metal, away from any carpet.
Think of the resistor as the light bulb. It's serving the very same purpose (providing resistance in the circuit), and get's hot, just like a light bulb (but it gets way hotter).
^^ This is for the driver's side. The passenger's side is the same idea, but you have to take the brake light off to access the light blue/black wires. There's a hole in the body for you to conveniently feed the wires through, so it's really easy.
I will stress again the importance of mounting the resistors safely and securely. Steel zip ties are available at Walmart and lots of other places I'm sure...so get those and you should be good to go. If you aren't sure about anything I've said and are doing this yourself, feel free to PM me, and I'll provide pics and try to explain it clearer...I kinda rushed through this post so I'm not sure if it's 100% clear. I did this earlier today, and everything works 100% right, even my turn signals, so this will certainly work. Also, I'm not an electrician. If somebody here is, and you see something wrong/stupid, PLEASE PLEASE correct me. I don't want to spread bad information!
Attachment 677377
Just to be clear - my issue was that after I installed LED tail lights (Anzo, if you were curious), my cruise control stopped working. Turn signals were a-okay, it was just the cruise that was messed up. After a lot of Googling, I quickly figured out that putting in a resistor of some sort somewhere would fix the problem...didn't get any real clear answers, but I figured it out - so here it is!
I got a couple 25W 6ohm resistors from autozone (they have a little kit specifically for this purpose - look in the light bulb section). The kit comes with 4 wire taps, as well. You don't have to cut any wires or anything, it's very easy.
- Pull the carpet back in the trunk, exposing the wires on the driver's side.
- Pull back the electrical tape on the bunch of wires there, and find a light blue one, and a black one. You will see the black one goes directly to a bolt in the center of the trunk for a body ground.
- Using the wire taps, connect the light blue with the black ground wire with the resistor. Be sure to leave yourself a good bit of wire to make it easy to mount the resistors somewhere safe (more on that later). I bought a coil of 18 gauge wire for this purpose, as well as a few more wire taps.
- Mount the resistor somewhere safe using steel zip ties (plastic might melt, those things ger really freaking hot. I mounted mine in the middle of the trunk by the latch, on the metal, away from any carpet.
Think of the resistor as the light bulb. It's serving the very same purpose (providing resistance in the circuit), and get's hot, just like a light bulb (but it gets way hotter).
^^ This is for the driver's side. The passenger's side is the same idea, but you have to take the brake light off to access the light blue/black wires. There's a hole in the body for you to conveniently feed the wires through, so it's really easy.
I will stress again the importance of mounting the resistors safely and securely. Steel zip ties are available at Walmart and lots of other places I'm sure...so get those and you should be good to go. If you aren't sure about anything I've said and are doing this yourself, feel free to PM me, and I'll provide pics and try to explain it clearer...I kinda rushed through this post so I'm not sure if it's 100% clear. I did this earlier today, and everything works 100% right, even my turn signals, so this will certainly work. Also, I'm not an electrician. If somebody here is, and you see something wrong/stupid, PLEASE PLEASE correct me. I don't want to spread bad information!
Attachment 677377
#49
TECH Resident
iTrader: (4)
I realize what they are calling a load equalizing resistor gets connected in parallel,
When I suggest a 470 ohm half watt resistor be used instead I mean for it to be connected with the tail lamp assembly in parallel, and not as an inline current limiting resistor.
I'm not sure why the oem tail light bulbs need to be simulated,
and is the premise that a load resistor has to be used on both the left & right tail lamp?
i would think you would only need to do one side, if you needed to do both sides with a load resistor for LED lamps then is that implying for the oem bulbs that if one tail light bulb goes out that your cruise control would not work?
I'm sort of curious as to what is happening electrically with the LED lamps causing the problems that were described.
When I suggest a 470 ohm half watt resistor be used instead I mean for it to be connected with the tail lamp assembly in parallel, and not as an inline current limiting resistor.
I'm not sure why the oem tail light bulbs need to be simulated,
and is the premise that a load resistor has to be used on both the left & right tail lamp?
i would think you would only need to do one side, if you needed to do both sides with a load resistor for LED lamps then is that implying for the oem bulbs that if one tail light bulb goes out that your cruise control would not work?
I'm sort of curious as to what is happening electrically with the LED lamps causing the problems that were described.
Has anyone done the work to see what level of resistance is sufficient to get the cruise working again? If the factory SS spoiler's LEDs work, I wouldn't be surprised if that particular CHMSL already has a resistor in it. Yes, the LEDs will all draw different current, but I'd bet that if we come up with a resistor which works for every possible LED, we'd still only have to make it only a tiny bit less efficient to cover for the possible variance among LEDs. It would be nice to test this once-and-for-all, and just say, "Buy this little X resistor, and it will fix your cruise."
#50
Save the manuals!
iTrader: (5)
#51
TECH Resident
iTrader: (4)
The larger units are bigger because they are wrapped in a heat sink. (Those fins dissipate heat from the resistor.) The small resistor creates the same heat but doesn't have a mechanism to deal with it - so you need to make sure you have things situated so that the resistor has air space and won't be touching anything, etc.
#52
Ungrounded Moderator
iTrader: (4)
But the standard load resistor for LED bulbs is only 6-ohms... that's next to nothing in the world of resistors. You can use 8-ohm resistors to get a very small decrease in heat but anything 10-ohms or higher starts to cause erratic turn signal function so it's likely that it would also fail to resolve the cruise problem.
The resistors will generally get about as hot as an equivalent incandescent bulb - that's plenty hot enough but as long as it's not physically touching a surface that could be damaged then it's not usually a problem. The resistor doesn't have to go close to the bulb so you could connect it anywhere in the CHMSL circuit including in the light blue wire under the dash near the left ground bolt behind the kick panel... plenty of room for air circulation and cooling.
The resistors will generally get about as hot as an equivalent incandescent bulb - that's plenty hot enough but as long as it's not physically touching a surface that could be damaged then it's not usually a problem. The resistor doesn't have to go close to the bulb so you could connect it anywhere in the CHMSL circuit including in the light blue wire under the dash near the left ground bolt behind the kick panel... plenty of room for air circulation and cooling.
#53
Just my 2 cents, but a lot of the better quality LED bulbs already have resistors built in, as your car/truck is 12v and LED's run average of 1.5-3v... Depending on how they are built, some are 3v max, some are 12v in series... These tend to be the cheaper ones..
Good Luck...
I hope this helps a little.
The attached webpage can help you find resistors if you're willing to wire them in yourself. You'll need some of the info from your bulbs tho.. It should be on the package, assuming they are of good quality, and not a 4.99 Chinese bulb.
http://www.ohmslawcalculator.com/led...her%20words...
Good Luck...
I hope this helps a little.
The attached webpage can help you find resistors if you're willing to wire them in yourself. You'll need some of the info from your bulbs tho.. It should be on the package, assuming they are of good quality, and not a 4.99 Chinese bulb.
http://www.ohmslawcalculator.com/led...her%20words...
#54
Ungrounded Moderator
iTrader: (4)
Just my 2 cents, but a lot of the better quality LED bulbs already have resistors built in, as your car/truck is 12v and LED's run average of 1.5-3v... Depending on how they are built, some are 3v max, some are 12v in series... These tend to be the cheaper ones..
Good Luck...
I hope this helps a little.
The attached webpage can help you find resistors if you're willing to wire them in yourself. You'll need some of the info from your bulbs tho.. It should be on the package, assuming they are of good quality, and not a 4.99 Chinese bulb.
http://www.ohmslawcalculator.com/led...her%20words...
Good Luck...
I hope this helps a little.
The attached webpage can help you find resistors if you're willing to wire them in yourself. You'll need some of the info from your bulbs tho.. It should be on the package, assuming they are of good quality, and not a 4.99 Chinese bulb.
http://www.ohmslawcalculator.com/led...her%20words...
The following users liked this post:
ramairjohn2000 (07-07-2020)
#55
TECH Regular
I'm not an electrician by any means but would putting a relay and using the resistance from the coil as in the thread below post 122 be a possible solution here?
https://ls1tech.com/forums/conversio...l#post16947626
https://ls1tech.com/forums/conversio...l#post16947626
#56
The fix for this is the same as several other GM models.
the cruise control module has a low voltage bleed out on the brake light wire. Installing a diode in line at the CC module on the brake wire fixes this.
On vehicles with drive by cable this is pin G lt Blu wire of the plug on the cc box under the hood.
the cruise control module has a low voltage bleed out on the brake light wire. Installing a diode in line at the CC module on the brake wire fixes this.
On vehicles with drive by cable this is pin G lt Blu wire of the plug on the cc box under the hood.