LED Tail Light Upgrades Can Disable Cruise Control

[canam175]

If you decided to upgrade your taillights to new LED style and found that when driving with headlights turned on and try using your cruise control to find it doesn't work. I did this on my 2001 Damon Daybreak thinking this is a good upgrade to all the older standard light bulbs, then I went on a trip to Florida and found at night when I had the head lights turned on the cruise control did not work. What I found out was the LED bulbs were causing a low voltage feedback through the brake light circuit which the computer determined was a brake activation and disengaged the cruise control. When I replaced the LED bulbs with the standard bulbs the cruise control would now function properly with the head lights turned on. If there is a solution, it's probably more expensive than just to use the standard bulbs.

 

[Mark_K5LXP]

Why fix what isn't broken?

Mark B.
Albuquerque, NM

 

[John From Detroit]

Two possible issues both fixed with the same part.
CANAM nailed one.. your cruse control may no longer work. or may not always work.

Two The lights may flash very fast, slow or not at all


Both of these are because the LED's do not draw enough current..
So a pair of resistors can be installed parallel with the STOP/TURN element
These draw the added current needed to make things work correctly

I know they used to sell them. don't recall the ratings but around the standard tail light is what. round 1.5 amps at 12 volt (18 Watt) so 8-10 ohms and to be safe 30 watts. If you can't find 30 watt.

a pair of 15 watt 15-20 ohm. or three 10 watt 30 ohm all parallel.

 

[NY_Dutch]

If you decided to upgrade your taillights to new LED style and found that when driving with headlights turned on and try using your cruise control to find it doesn't work. I did this on my 2001 Damon Daybreak thinking this is a good upgrade to all the older standard light bulbs, then I went on a trip to Florida and found at night when I had the head lights turned on the cruise control did not work. What I found out was the LED bulbs were causing a low voltage feedback through the brake light circuit which the computer determined was a brake activation and disengaged the cruise control. When I replaced the LED bulbs with the standard bulbs the cruise control would now function properly with the head lights turned on. If there is a solution, it's probably more expensive than just to use the standard bulbs.

I installed 50 watt 6 ohm load resistors when I upgraded my 2001 Landau to LED's. Never had a problem with the cruise control, rapid flashing, etc.

Amazon.com

 

[TheBar]

Why fix what isn't broken?

Mark B.
Albuquerque, NM

A dozen years ago a friend had an 80's Malibu with the brake lights in the bumper. After getting hit from behind at a couple stop lights he replaced with much brighter LEDs. He had to take it to a dealer to find out why his cruise control quit working. Back then resistors weren't available but he decided to keep the LEDs over getting hit from behind.

 

[canam175]

A dozen years ago a friend had an 80's Malibu with the brake lights in the bumper. After getting hit from behind a couple lights he replaced with much brighter LEDs. He had to take it to a dealer to find out why his cruise control quit working. Back then resistors weren't available but he decided to keep the LEDs over getting hit from behind.

To avoid this possibility, I also added a light bar to my motor home, no stupid diver excusses!

 

[tlmgcamp1]

To avoid this possibility, I also added a light bar to my motor home, no stupid diver excusses!

"Because the lights were so bright, I couldn't see the motorhome and ran into it "

Never underestimate the potential for stupidity

 

[Mark_K5LXP]

It's also not legal. There are DOT standards for vehicle lighting. Height, surface area, spacing, hue and brightness. Changing an incandescent bulb to LED likely changes hue and brightness. Just because one might consider it 'better' doesn't make it so. If the LED is in a DOT approved assembly then that's a different story but you don't often hear of folks doing that. 1156/1157 bulbs are cheap, quick and durable enough.

Mark B.
Albuquerque, NM

 

[Kirk]

Light Bulb with Built-in Resistor 2357 Brake Light Bulb​

 

[House Husband]

I had the same cruise control/torque converter issue when I installed LED tail lights.
I installed 194 bulbs behind the LEDs. That cured the grounding problem for me.

 

[Mark_K5LXP]

The hazard (sic) of putting LED bulbs in place of incandescent is bulbs of appreciable lumens will not be adequately heatsinked in an incandescent socket. Incandescents can get stinkin' hot and it doesn't matter. LED's generate less heat but if it has nowhere to go they roast and fail. Retrofit LED light assemblies are made with this in mind. Additionally the color spectrum of LED is different than incandescent and can make colored lenses look wrong or dim. It's so much simpler to put in an 1156/1157 and done.

Mark B.
Albuquerque, NM

 

[NY_Dutch]

The hazard (sic) of putting LED bulbs in place of incandescent is bulbs of appreciable lumens will not be adequately heatsinked in an incandescent socket. Incandescents can get stinkin' hot and it doesn't matter. LED's generate less heat but if it has nowhere to go they roast and fail. Retrofit LED light assemblies are made with this in mind. Additionally the color spectrum of LED is different than incandescent and can make colored lenses look wrong or dim. It's so much simpler to put in an 1156/1157 and done.

Mark B.
Albuquerque, NM

When replacing incandescent bulbs with LED's, use the same color LED as the lens.

 

[RayIN]

Two possible issues both fixed with the same part.
CANAM nailed one.. your cruse control may no longer work. or may not always work.

Two The lights may flash very fast, slow or not at all


Both of these are because the LED's do not draw enough current..
So a pair of resistors can be installed parallel with the STOP/TURN element
These draw the added current needed to make things work correctly

I know they used to sell them. don't recall the ratings but around the standard tail light is what. round 1.5 amps at 12 volt (18 Watt) so 8-10 ohms and to be safe 30 watts. If you can't find 30 watt.

a pair of 15 watt 15-20 ohm. or three 10 watt 30 ohm all parallel.

What you're saying is, return to incandescent bulbs to correct the problem, OR, spend money to install resistors that draw enough current to make everything work with LED's.

 

[John From Detroit]

What you're saying is, return to incandescent bulbs to correct the problem, OR, spend money to install resistors that draw enough current to make everything work with LED's.

I would go with the resistors as the LED's last longer and long term that's the lower cost solution.

 

[Mark_K5LXP]

You can buy a dozen 1157's for one LED bulb, for economy stick with incandescent. LED projector array headlights might illuminate a bit better than halogen but at a hefty price. I've changed out the $12 halogens in my 30 year old pickup once so far. For RV interior lighting on battery power LED is the answer. Not sure what problem they solve as running or taillights. If you have to band aid it with ballast resistors or voltage regulation sounds like a lot of unneccesary work to me.

Mark B.
Albuquerque, NM

 

[NY_Dutch]

You can buy a dozen 1157's for one LED bulb, for economy stick with incandescent. LED projector array headlights might illuminate a bit better than halogen but at a hefty price. I've changed out the $12 halogens in my 30 year old pickup once so far. For RV interior lighting on battery power LED is the answer. Not sure what problem they solve as running or taillights. If you have to band aid it with ballast resistors or voltage regulation sounds like a lot of unneccesary work to me.

Mark B.
Albuquerque, NM

LED's last a long time and light up slightly quicker than incandescents. There's a reason that most current cars and trucks have gone to LED's

 

[Larry N.]

LED's last a long time and light up slightly quicker than incandescents. There's a reason that most current cars and trucks have gone to LED's

You might note that LED assemblies are much more expensive to replace, too. When I bought my 2025 Ford Maverick AWD, I found out that it's about $1,300 for one. Yep, Thirteen Hundred for one.

Another example was my 1989 Ford Ranger 4WD in which I only replaced one headlight in the 14 years and 113,000 miles that I had it. And during most of those years I worked midnight to eight, with 30-40 minutes to work, not counting long trips with large segments in many cases done after dark.

And so far I'm not seeing enough improvement in night time seeing with the LEDs to matter, but I do note that headlight glare (partially blinding me) is often worse from the newer vehicles with LEDs, particularly on terrain that effectively raised the oncoming vehicle's nose a bit rather than being on flat terrain.

 

[NY_Dutch]

Another example was my 1989 Ford Ranger 4WD in which I only replaced one headlight in the 14 years and 113,000 miles that I had it. And during most of those years I worked midnight to eight, with 30-40 minutes to work, not counting long trips with large segments in many cases done after dark.

And so far I'm not seeing enough improvement in night time seeing with the LEDs to matter, but I do note that headlight glare (partially blinding me) is often worse from the newer vehicles with LEDs, particularly on terrain that effectively raised the oncoming vehicle's nose a bit rather than being on flat terrain.

So it would seem that car makers did not go to LED's to cut costs. There must be another reason. My 2025 Subaru has self leveling headlights, so the terrain should not be a factor.

 

[the4quads]

I would go with the resistors as the LED's last longer and long term that's the lower cost solution.

I did the LED upgrade and used these's. It's been over 5 years and works great.