Lights Dim When Brake Is Applied, Windows Rolled Down...

johnsonjf · July 22, 2007

Hey guys, second forum topic...I'm on a roll!

I was cruising around in my 2007 4.8L Silverado 900 series truck earlier tonight when it was just after dark and noticed that when I am stationary at a light, or if I am in park pressing the brake to shift into a gear, the lights dim down a bit on me. It also does it if I roll down an electric window or turn on my interior lights.

I had a friend who got a 2003 silverado new and he said it always happened to him. However, all my stuff is still stock unlike his (he had in-dash DVD and all that).

I guess I am just jittery about this truck since other stuff is in need to adjustment on it. This is also my first brand new truck I bought (and the first chevy I've owned), so I am slightly dissapointed that I need to goto the dealership to have stuff adjusted (aka the shaking in my driver's side mirror etc etc see my other post).

Let me know what is up. Like I said, bone stock (well I've got an XM radio plugged into the cig lighter), with less than 1,000 miles on it. Thanks in advance.

pwall · July 22, 2007

Without waiting until tonight to test, I'm quite sure my 2002 does the same thing.

At idle, the alternator is not putting that much out and power windows draw a fair amount of power.

Ranger · July 22, 2007

My lights do dim whenever I roll the windows up, not sure about the brake thing though but I'm sure it's normal cause there are a lot of electronics on these vehicles and they're all drawing power from that "little" 105 amp alternator.

My mirrors shake also at highway speeds, that's a normal thing unfortunately...Has to do with the way the mirrors are shaped. Large surface against high winds makes the mirror vibrate.

Green_Monster · July 23, 2007

Mine does the same things including dimming lights when I tap the brakes, such as when "cancelling" the cruise control. Mine doesn't do it when I put it into gear though.

johnsonjf · July 23, 2007

Well by "putting it in gear" i mean the motion of pressing down the brake so I dont lurch forward.

It sounds pretty normal afterall then.

phattball · July 27, 2007

Hey guys, second forum topic...I'm on a roll!

I was cruising around in my 2007 4.8L Silverado 900 series truck earlier tonight when it was just after dark and noticed that when I am stationary at a light, or if I am in park pressing the brake to shift into a gear, the lights dim down a bit on me. It also does it if I roll down an electric window or turn on my interior lights.

I had a friend who got a 2003 silverado new and he said it always happened to him. However, all my stuff is still stock unlike his (he had in-dash DVD and all that).

I guess I am just jittery about this truck since other stuff is in need to adjustment on it. This is also my first brand new truck I bought (and the first chevy I've owned), so I am slightly dissapointed that I need to goto the dealership to have stuff adjusted (aka the shaking in my driver's side mirror etc etc see my other post).

Let me know what is up. Like I said, bone stock (well I've got an XM radio plugged into the cig lighter), with less than 1,000 miles on it. Thanks in advance.

My 05 1500 does the same thing man. Its no big deal. Like someone said earlier when idleing the alternator does not produce enough curent for the amount you are drawing. But as soon as your moving again it produces more than enough.

avmech · October 6, 2007

03 Sierra and 07 Yukon both do it. My 99 Silverado did it too. As far as the mirror, the Yukon had the driver side mirror with the shakes. Dealer replaced it, OK now................you could shake the mirror in the housing by hand