LED Brake Light Bulbs Will Disable Cruise Control on GMT800

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Rocket Man

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Lol the resistor just gets the circuit within the minimum needed to fool the system, you’re still saving a picowatt of energy over a months time. I mean, that’s why I run leds in my vehicles. I hate it when my truck sends me a big bill for electricity. Same with the gas bill. :insane:
 

adventurenali92

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. I’m trying to noodle why this is; something about the amount of resistance in the circuit the Cruise Control monitors to turn off when brakes applied, but I can’t figure this out since the Cruise Control surely does not put current in the brake lamp circuit.


Someone more knowledgeable, correct me if I’m wrong, but As I understand it cruise control not working with LED bulbs in the brake lights is GM’s built in safety feature at work. It doesn’t have anything to do with cruise control adding resistance to the brake lamps circuit. If the system detects not enough voltage or resistance going to the brake lights, it assumes one or more brake light bulbs is blown, and then disables cruise control, as a safety measure. which I also don’t understand the logic in that either. Like ok “my brake lights are out, how is disabling cruise control going to make that scenario safer?!” But what do I know… lol.
 

adventurenali92

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Lol the resistor just gets the circuit within the minimum needed to fool the system, you’re still saving a picowatt of energy over a months time. I mean, that’s why I run leds in my vehicles. I hate it when my truck sends me a big bill for electricity. Same with the gas bill. :insane:
Laughing cuz That’s where my brain went as well when I read the bit about losing the LED efficiency when adding resistors….. I’m really worried about the electrical efficiency in my big gas guzzling SUV…. :Big Laugh:
 

Burban22

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What is the part number or link to replacement rubber washers that go in the rear turn, reverse, brake bulb sockets?

My driver side taillight has all 3 but passenger side missing so the bulbs are loose in the plastic taillight housing along with dust and water able to enter.
 

Rocket Man

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What is the part number or link to replacement rubber washers that go in the rear turn, reverse, brake bulb sockets?

My driver side taillight has all 3 but passenger side missing so the bulbs are loose in the plastic taillight housing along with dust and water able to enter.
That’s a generic part available at your local auto parts store. They should have a rack with little parts like that, Dorman usually has racks with what they call “FixIt” parts. Take one of the ones you have with you to match up but bulbs are all the same size from car manufacturer to car manufacturer, so there’s no GM ones versus Fird ones, they’re like rubbers everybody uses the same ones. ;) :happy107:
 

DmitryGMT800

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Lol the resistor just gets the circuit within the minimum needed to fool the system, you’re still saving a picowatt of energy over a months time. I mean, that’s why I run leds in my vehicles. I hate it when my truck sends me a big bill for electricity. Same with the gas bill. :insane:
Switching to LEDs in brake lights would bring more safety as LED response is a bit faster than ordinary bulbs. Which in turn grants some time for driver to react. It can be seen how a vehicle ahead of me has a delay between the brake lights and the third brake light which is LED. Of course I would not not expect energy savings from this type of things :) LED is somewhat brighter as well - though it may depend on the specific model. By the way - I just wanted to share my issue with the LED in brake lights - right brake light led bulb is on all the time - but it has 2 volts and is very dim if compared to normal mode and braking mode... Does anybody witnessed this?
 
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