2015 RAM Headlights flickers

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Occasionally my RAM 1500 headlights will flicker. I have read others have noticed this as well. They don't go out, just lightly flicker for a brief second every now and then. No patternt that I can tell.

Anyone heard of this or maybe what it is?

thanks
 
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That's super common amongst 4th Generation Chrysler minivans.The Feds dropped complaints without a finding years back,but to some its almost like they have strobe lights which make the vehicles not road legal.Many theories from a bad battery,bad alternator,dirty battery cables,bad connections at the "forward control module" and/or power distribution box,to bad grounds or just the way the Chrysler voltage system is regulated....
 
Originally Posted By: NHGUY
That's super common amongst 4th Generation Chrysler minivans.The Feds dropped complaints without a finding years back,but to some its almost like they have strobe lights which make the vehicles not road legal.Many theories from a bad battery,bad alternator,dirty battery cables,bad connections at the "forward control module" and/or power distribution box,to bad grounds or just the way the Chrysler voltage system is regulated....


My 01 Grand Caravan has this exact issue. I can't figure out why.
 
Originally Posted By: Farmer
Originally Posted By: NHGUY
That's super common amongst 4th Generation Chrysler minivans.The Feds dropped complaints without a finding years back,but to some its almost like they have strobe lights which make the vehicles not road legal.Many theories from a bad battery,bad alternator,dirty battery cables,bad connections at the "forward control module" and/or power distribution box,to bad grounds or just the way the Chrysler voltage system is regulated....


My 01 Grand Caravan has this exact issue. I can't figure out why.
See if it happens when the Radiator cooling fans come on.
 
Originally Posted By: Chris142
Originally Posted By: Farmer
Originally Posted By: NHGUY
That's super common amongst 4th Generation Chrysler minivans.The Feds dropped complaints without a finding years back,but to some its almost like they have strobe lights which make the vehicles not road legal.Many theories from a bad battery,bad alternator,dirty battery cables,bad connections at the "forward control module" and/or power distribution box,to bad grounds or just the way the Chrysler voltage system is regulated....


My 01 Grand Caravan has this exact issue. I can't figure out why.
See if it happens when the Radiator cooling fans come on.


It happens when its off, and randomly while I'm driving.
 
03-05 Crown vics had this issue, and it was bad relays in the lighting control module. Well, they aren't bad, they are a good relay spec'd to the limit of their load handling capability to save a few pennies. Add in a few years and they start flickering and ultimately fail.
So, my suspicion would be what ever relays are turning them on. Unless they are HIDs in which case I might suspect the ballast.
 
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Where's the regulator in the system, in the alternator, or built into the main CPU? If it's in the alternator it could be anything from worn brushes (easy fix) or a regulator going bad, to a flaky ground between the alternator body and the engine, or from the engine to the body. Sometimes an extra ground wire between the alternator body and the car body will help.
 
Put a set of headlight relays in, problem solved and the trucks electrical system will thank you for years down the road
 
Probably too small of wiring. Use at least 16ga and 14ga is better. The factory relays are only as good as the factory wire.
 
The truck may have a headlight control module that switches and monitors the bulb current. Its what gives you a dash warning if a bulb goes out. I could be much more complex than a switch, wiring, and some relays. I seem to remember something about this when I had my 2004 Ram. I recall it flickering the headlights when the ABS would go through its BIT (built in test). IIRC it was first excursion through 5 MPH at each start-up. On the forums back then some guys were having issues with headlights and it turned out to be a $300 headlight control module.
 
Originally Posted By: SteveSRT8
The headlights already have a relay...


I'll bet the current still goes through a body control module, though. NHGUY is correct about the FCM/BCM on the Chrysler minivans. The new Ram is obviously a different vehicle, but I'll bet there's a similar concept. In other words, I'm pretty sure the headlamp current doesn't run straight from the battery to the headlamps.

If you run your current straight from the battery yourself, through a relay connected to the OEM plugs, then you'll avoid this issue.
 
Originally Posted By: JetStar
The truck may have a headlight control module that switches and monitors the bulb current. Its what gives you a dash warning if a bulb goes out. I could be much more complex than a switch, wiring, and some relays. I seem to remember something about this when I had my 2004 Ram. I recall it flickering the headlights when the ABS would go through its BIT (built in test). IIRC it was first excursion through 5 MPH at each start-up. On the forums back then some guys were having issues with headlights and it turned out to be a $300 headlight control module.


I've seen 2 kinds of flicker.

1. momentary drops: guys that try to convert to HID's run into this. something about how it tests for a bad bulb is it cuts power for brief moments. a filament bulb won't go out during the quick drop but an HID shuts off and cycles. They don't like to use a resistance shunt in the test circuits because of the potential miniscule drop in voltage. So they do something else--- which causes the flicker. I've never looked into the theory of operation.

2. ongoing unsteady voltage. 3 of the 4 chryco products I've owned has had lumpy voltage. There's always this very mild, random fluctuation that if you really pay attn happens in all lamps, including the cluster. I've tried batteries, auxiliary grounds, fuses, filters... none made a difference, and none left me stranded from a voltage issue.
 
if it never gets worse, then it's likely #2 above. I drove all of mine for years like this and never had an issue.
 
Use the OEM output to fire a relay coil. Wire the relay power through a fuse to the battery with at least 14 ga wire. Problem solved.
 
Originally Posted By: Nutshell
I switched to LED's on my 15. Problem solved.


Terrible and stupid idea. Please do not listen to anyone who tries to tell you that you can drop in an LED bulb into a halogen bulb part number and have an upgrade, it's a huge downgrade in every way.

There is a reason that no reputable manufacturers make these parts because they are illegal Chinese toys shaped like automotive parts
 
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