About a week ago all my lights started to "flicker" for lack of a better word when all of them are on. I have not noticed it with just the park lights on but it may be becuae it is just not dark enough to notice it. It is normally fairly consistent with being around every 4-5 seconds they with dim out really quick. Almost looks like I flash my lights. Could this be my alternator or regulator in my alternator. My voltage guage always reads good, never changes when this happens. Any thoughts on what it could be and how to check the alternator?

 

assuming that it's not your grids cycling...

If you wiggle the **** on the switch around and you can see it changing or flickering from the movement i would say headlight switch.

 

Does it go away once you drive over 20 mph? If they stop flickering its your air heater grid turning on and off.

 

Well I wouldn't say its the grids cycling because he said his voltage meter never changes.

 

If you ever figure this out, PLEASE EMAIL ME!

I've been searching for a soulution to this since last August!

And if you pay close attention, you will hear the engine sync with the lights.... trust me.

I have NO IDEA what it is.

 

I do not think its my grid heaters cycling because it will continue at cruising speads. I did have an exhaust manifold gasket blow out for about a week and it was blowing exhaust/smoke pretty much right at my alternator. Could this have anything to do with it?

 

my truck does this also.but i think it is because i have an external voltage regulater.instaed of the one in the ecm.My stock regulater went out.But digital bullet is right you can hear my engine with the pulses also and the truck rocks slightly when idleing.its kinda cool the truck rocking and all but the pulseing lights do get anoying.

 

Does anyone have a CLUE what could cause this?

 

does it happen with the defrost on? such as when the A/C clutch kicks in?

 

If they don't flicker full off/on, but just dim 10-20%, it is almost certainly your grid heater cycling. Check the voltage guage, it will sweep down when the grid heater turns on. This heater is in the intake, it heats the intake air before starting and after starting, before the truck warms up, to help the engine start and run better in the cold. It cycles (turns on/off, instead of just staying on), and draws a lot of current.

It draws enough current when it turns on to pull down the voltage of the whole electrical system, so this causes the voltage guage sweep/light intensity change. It is normal and not of concern.... except if your heaters do it when they really shouldn't (e.g. your engine is warm and has been running for some time). In that case, I would look into the control circuits for the heater.

If this is what is going on, it also explains the change in the engine - the additional draw from the alternator puts enough additional load on the engine to change the tone slightly! Again, normal, and nothing to worry about. It should go away when the engine heats up.

 

if they flicker at an Idle and it's nothing to do with grids...

You might at an idle try pulling some fuses one at a time, then plug back in, just a chance that you may find the circuit that the culprit is in this way.

 

its not the heater grids the amp gauge doesnt even move.They flicker real fast like ever 2 seconds.it dosnt matter if the lights are on bright,dim,parking lights it will do it driving down the road at 75 or 80 mph

 

If it's only happening at 75-80mph, try unplugging your wheel speed sensor.

It may throw a code, but see if it still does it unpluged at 75-80mph.

 

Can you smell that "electrical" smell in the cab? I have been driving down the road and my dash lights and everything has flickered on and off. I have noticed it is the headlight switch itself. I have replaced two and ready to replace another and they have been melted and burned. Does anyone know of any recalls on the switch cause i am sick of buying new ones and throwing melted and burned ones away.

 

Does your lights flicker when you move the tilt wheel? There is wire that comes loose inside the multifunction switch, I think it is purple and white.