[012chevy012]

Hello silverado owners, here's another problem i just noticed, maybe somebody else has noticed too.
When I step on the brakes the headlights flicker a little when idling, just noticed the other night.

 

[ferraiolo1]

not normal.. issue with your battery or charging system.

 

[GR2017]

Depending on what loads the system is under while at idle, this may be perfectly normal. Certainly normal for vehicles in the past.

 

[ferraiolo1]

GR ya have to stop comparing vehicles of the past to current vehicles. Its not normal on modern vehicles.

 

[jaijoseph]

I noticed the same thing on my 14 Sierra. I was suspecting the alternator, even when I turn the wheel left to right the lights dim. I already had the battery replaced.

 

[Toms2014SLTAT]

As I found out yesterday, the OE battery in our trucks does not last for shit. I would start there. Also remember that we have a variable load alternator as well.

 

[ferraiolo1]

We do, but it only switches to a lower charge rate when there isn't a load on the system. so if his lights AC or any other accessory are on the alternator shouldn't be in that setting.

 

[wildchevy]

Totally normal to see headlight dimming in 06 and up trucks equipped with the fuel saving charging system, it is slow to react to extra demands like brake lights and power window usage. The alternator is controlled by a module and keeps drag on engine to a minimum in order to increase MPG. I have experienced the same thing on my 06 09 12 14 and 16 trucks from day one on each truck.

 

[ferraiolo1]

my 08 and 15 never did it. Charging system always kept up. If the lights are on it shouldn't be in the power saving mode.

 

[wildchevy]

Hello silverado owners, here's another problem i just noticed, maybe somebody else has noticed too.
When I step on the brakes the headlights flicker a little when idling, just noticed the other night.

flicker is that a constant flicker or just once as the brake lights come?

 

[Gozzie]

I think if you watch the volt meter at the same time you can tell which mode it's in when it happens. It may have to do with radio and heater on and lights (heavier load) vs light load and then what stage the battery is in at that time . Charged or charging. Study it long enough and I bet you can tell when it's going to happen. I think everyone is right here. Battery condition makes difference.

 

[SilmarilS]

Totally normal to see headlight dimming in 06 and up trucks equipped with the fuel saving charging system, it is slow to react to extra demands like brake lights and power window usage. The alternator is controlled by a module and keeps drag on engine to a minimum in order to increase MPG. I have experienced the same thing on my 06 09 12 14 and 16 trucks from day one on each truck.

Exactly....

I had the same pattern on my 13 and my previous Mazda 3...

You can't put a 20+amp load on a electrical system and don't see a little drop in voltage.
Some people don't notice it, but you can measure it with a good mulitmeter.

 

[012chevy012]

just when i step on the brakes

 

[wildchevy]

so they flicker or just dim and then return to normal, a flicker is like the light a candle gives off.