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HID relay buzzing with capacitors after kit install

24K views 85 replies 6 participants last post by  Shooter2384 
#1 ·
Hey guys, I got the elite 9006 kit from the retrofit source installed in my 2013 ATS luxury. Even with an HD relay and a capacitor on each headlight the relay buzzes almost constantly. The right headlight where the relay is even shut off on me while driving last night. As soon as the light shut off the buzzing stopped. Then today I started my car and no buzzing until I let it sit for a little bit. Any thoughts on what it could be? This also got installed professionally at a shop who installs VVME kits so I highly doubt the workmanship is at fault.
 
#27 ·
Ok, that makes more sense. I guess based on your above example when you put the light there, I wasn't accounting for the ballast.
1. So based on the diagram above, ballast input is connected to relay output and thats it.
2. One capacitor connects to the input from car on the relay, and it doesn't matter which headlight that capacitor is plugged into, correct?
3. I don't think I understood that the relay was acting as the switch, and that's what was confusing me.
 
#32 ·
Wasn't able to get the bumper off this weekend but from what it sounds like one side is hooked up correctlyfrom the relay I put to the factory input or output whatever it's called, and the other capacitor is between the ballast and relay. Would this cause an issue? I have an appointment next Wednesday and then I can get actual photos of the install.
 
#34 ·
The input power being the bulb to the capacitor, then capacitor to the ballast or the capacitor being placed between ballast and relay?

Unrelated, but do you know if I can purchase premium or performance trim fog lights and put them into my luxury trim? Is the wiring already there for those?
 
#40 ·
Gotcha. I have a strong feeling it's just something not hooked up right and the product is fine considering sometimes both DRL's will run for a bit before the right finally flickers and shuts off. The relay buzz also doesn't always start right away either but it seems when it buzzes the light will eventually go out. What exactly is the point/benefit of hooking the capacitors up as Bulb to cap, cap to ballast? What issues could potentially arise/what should I look for?
 
#41 ·
Where i say bulb, it's actually the power coming from the factory headlight connector. So the capacitor is going there to smooth the power to the ballast, which will make it run more reliably. You will see three connectors coming off the HID bulb on the outside of the rubber gasket. The capacitor can only plug into one of them, the other two are power to the bulb from the ballast. If you look again at the picture I posted above of the HID bulb, the connector next to the bulb is just a pass through to get the power out to the ballast (or trigger the relay when using a relay harness).
 
#42 ·
Right I understand that. I shouldn't have said bulb and saved you the time to type that. But again, what issues could potentially arise/what should I look for? Someone else told me the capacitors won't have any effect when plugged into the ballast at all.
 
#43 ·
True, connected at the ballast when using a relay harness, it shouldn't have any affect. If the relay is chattering it may smooth out the 12v as it is supposed to do. But it wouldn't necessarily be clean enough to keep that ballast running, which could be why it's still going out on you.

You're only having an issue during DRL operation?
 
#44 ·
That's correct. And it's only the right side. I realize you know your stuff I guess I just don't see the benefit of trying to attach it that way...I guess I don't get how it will smooth out the chatter when it's installed in a way that's not supposed to have an effect, but I can try. I'm hoping hell just let me be back there with him most of the time so I can keep a record of trial and error.
 
#45 ·
>1000uF capacitor needed on input side of relay

To add OE HID's to a vehicle, we reprogram the BCM as per TRIFECTA procedure requirements as part of the TRIFECTA vehicle configuration retrofit process. AFS will require a new headlight harness; the OE headlight harness is both keyed differently and pinned differently vs the halogen headlights.


However though, what you are attempting can be solved mechanically as well:

You will need to add a >1000uF 35V capacitor on the signaling INPUT side of the relay.

The headlight low beam (+) line has a self test cycle that pulses the supplied power at ~5HZ or so for sometimes up to a full second.

When the ambient light sensor on your dashboard detects sustained light input, the vehicle will pulse the low beam (+) line at ~10HZ continuously.

It is not the supplied voltage to the ballast that is being irregular, but the supplied power to the relay that is causing the relay to pulse the power to the aftermarket ballasts that is causing what you are experiencing.
 
#50 ·
The other guy pmed me and said "1000uF may not be enough, but too large of a capacitor will cause the headlights to stay on after cutting power for an extended duration. Maybe 3500uF?" So what the heck do I go with? He was also talking about reprogramming the BCM and I could avoid all this modification to the harness but I don't know what that is, what it does or how to get it reprogrammed.
 
#51 ·
right now your best bet is to work with what you have. wait till the appointment and have them check/change the capacitors. again, i would also connect the ballasts without the relay harness as an option.

im not sure what the load of the circuit would be so its tough to say how long the cap will hold a charge, but with a 1000uF cap i dont think you will see a delay in turning off the headlights. i would go with 1000uF if you attempt this, if option 1 fails.

BCM is Body Control Module, basically a computer in the car. In the ATS, The BCM controls the DRL/Headlight functions and can be reprogrammed using the OBD port under the dash to turn off the DRLs, but i have not come across anyone openly offering this service.
 
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