HID conversion - - Resistors Necessary?
Thread Starter
Running Guns & Moonshine
Joined: Aug 2001
Posts: 12,547
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From: CT
HID conversion - - Resistors Necessary?
The fog, low and high HID kits came with a total of three in-line resistors to install.
I'm thinking I need to order 3 more. One for each bulb.
Are these necessary for HID conversions, or are they precautionary?
The reason I ask is that I will just do one side of the car and hold off it they're necessary. Otherwise, I'll wire everything up and then splice when they come in.
Edit: OR... I might just be asking a stupid question. The install instructions mention a resistor for installation in-line, but the resistors I have are to avoid hyperflash when I do the front corner signals.
I'm thinking I need to order 3 more. One for each bulb.
Are these necessary for HID conversions, or are they precautionary?
The reason I ask is that I will just do one side of the car and hold off it they're necessary. Otherwise, I'll wire everything up and then splice when they come in.
Edit: OR... I might just be asking a stupid question. The install instructions mention a resistor for installation in-line, but the resistors I have are to avoid hyperflash when I do the front corner signals.
Last edited by Tusc; Nov 20, 2012 at 12:51 PM.
Instructor
Joined: Jun 2009
Posts: 107
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From: Knoxville TN
I installed a resistor on my low beams to have the headlights go down. However, they didn't do anything to help me. I then took out the resistor and went with a relay.
If your headlights don't go down you flash your hi beams to get them working. The car believes a light is out and leaves them in the up position. That is the reason for a resistor...since the hids consume less wattage. Also, you do not need a resistor for each bulb. Ideally, one in line will do the trick.
edit - I'm not sure about a hyperflash resistor. I used a guide off here to install my own hyperflash relay. Spliced it in and came out cheaper than buying a premade one.
If your headlights don't go down you flash your hi beams to get them working. The car believes a light is out and leaves them in the up position. That is the reason for a resistor...since the hids consume less wattage. Also, you do not need a resistor for each bulb. Ideally, one in line will do the trick.
edit - I'm not sure about a hyperflash resistor. I used a guide off here to install my own hyperflash relay. Spliced it in and came out cheaper than buying a premade one.
Last edited by sereneDelusions; Nov 20, 2012 at 01:00 PM.
Thread Starter
Running Guns & Moonshine
Joined: Aug 2001
Posts: 12,547
Likes: 7,232
From: CT
I have time today (and warm weather) to work on this issue. I am mid-search now for an answer and found this original post of mine.
My question now is where to install the resistor to get the motors to function.
My question now is where to install the resistor to get the motors to function.
Tech Contributor
Joined: Aug 2008
Posts: 2,902
Likes: 21
From: Oak Hill Virginia
I have no idea why you got three separate inline resistors with your kits; I've never seen a kit come with one. They usually need to be ordered separately. The only kit you need a resistor for is the low beams. If you don't have a inline resistor installed with your low beam kit your light buckets will not retract properly. You only need ONE inline resistor for your lows. You do not need one per side.
BUT; are you sure that what your kit came with was resistors and not relay harnesses?
BUT; are you sure that what your kit came with was resistors and not relay harnesses?
Race Director
Joined: Apr 2007
Posts: 11,150
Likes: 890
From: South Western Ontario
I would not put resistors in for LED lights. Install a pre-made flasher bypass harnes or spend $5 and do it yourself.
As for the HID lights. You might need one on the low beams to get the lights to retract when on low beam. The resistor installs in between 2 connectors. It is wired in parallel or across the ballast to provide some extra load.
As for the HID lights. You might need one on the low beams to get the lights to retract when on low beam. The resistor installs in between 2 connectors. It is wired in parallel or across the ballast to provide some extra load.
Melting Slicks
Joined: Mar 2009
Posts: 2,300
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From: Odessa FL
St. Jude Donor '10-'12-'13-'14-'15-'16-'17
As mentioned above, you will not need a resistor for your HID fogs or high beams. You will need one on the HID low beams. If you are not using a relay wired for power direct from the battery wire the resistor between the OEM low beam socket and the ballast on one side only. If you are using a relay harness wire the resistor between the relay power out socket and the ballast on one side only. This will ensure that the light buckets lower without having to turn on the high beams to do so.
JW motorsports makes a resistor that is pre wired with the correct sockets and is a plug and play install. Be sure you have the polarity correct when plugging everything in.
As mentioned also there are vendors with prewired harnesses to keep from having hyper flash with LED conversions as well. These are not the same as the resistors mentioned above. Hope this helps.
JW motorsports makes a resistor that is pre wired with the correct sockets and is a plug and play install. Be sure you have the polarity correct when plugging everything in.
As mentioned also there are vendors with prewired harnesses to keep from having hyper flash with LED conversions as well. These are not the same as the resistors mentioned above. Hope this helps.
Race Director
Joined: Apr 2007
Posts: 11,150
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From: South Western Ontario
I'm not sure why you'd want the resistor between a relay and the ballast. It will do absolutely nothing to help the headlights retract. If the headlights don't retract then you'd want the resistor wired in parallel to the coil of the relay.
Melting Slicks
Joined: Mar 2009
Posts: 2,300
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From: Odessa FL
St. Jude Donor '10-'12-'13-'14-'15-'16-'17
Not an electrical expert. The instructions have it being placed between one of the sockets from the relay (87) and the ballast. Without it my lights would not lower until I turned the high beams on. After installing the resistor as mentioned on the passenger side low beam ballast only they retract without issue.
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Race Director
Joined: Apr 2007
Posts: 11,150
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From: South Western Ontario
Not an electrical expert. The instructions have it being placed between one of the sockets from the relay (87) and the ballast. Without it my lights would not lower until I turned the high beams on. After installing the resistor as mentioned on the passenger side low beam ballast only they retract without issue.
Last edited by lionelhutz; Dec 3, 2012 at 08:44 PM.
Melting Slicks
Joined: Mar 2009
Posts: 2,300
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From: Odessa FL
St. Jude Donor '10-'12-'13-'14-'15-'16-'17
That makes no sense. If the original headlight wiring goes to the coil of the relay and the relay contact is connected between the battery and the ballast then wiring a resistor to the ballast would have no connection to the original wiring and it could not affect the operation of the headlight motors. The resistor needs to connect to the original headlight wiring to have an effect.
Melting Slicks
Joined: Mar 2009
Posts: 2,300
Likes: 115
From: Odessa FL
St. Jude Donor '10-'12-'13-'14-'15-'16-'17
That makes no sense. If the original headlight wiring goes to the coil of the relay and the relay contact is connected between the battery and the ballast then wiring a resistor to the ballast would have no connection to the original wiring and it could not affect the operation of the headlight motors. The resistor needs to connect to the original headlight wiring to have an effect.
Le Mans Master
Joined: Oct 2010
Posts: 7,373
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From: cold & windy
that was going to be my question - what wattage HID kits are y'all running?
not having tried it myself (or remembering anyone specifically talking about it), you'd think using a 55W low beam kit wouldn't have this issue since that's the wattage of the stock 9006 bulbs.
i understand that with the crappy dispersion pattern of the factory housings, a 55W system gains you nothing (other than angrier oncoming traffic), but for those of us with the pop-up ACA projectors, the 55W would be a benefit.
would i still need the resistor for 55W low beams?
not having tried it myself (or remembering anyone specifically talking about it), you'd think using a 55W low beam kit wouldn't have this issue since that's the wattage of the stock 9006 bulbs.
i understand that with the crappy dispersion pattern of the factory housings, a 55W system gains you nothing (other than angrier oncoming traffic), but for those of us with the pop-up ACA projectors, the 55W would be a benefit.
would i still need the resistor for 55W low beams?
Le Mans Master
Joined: Oct 2010
Posts: 7,373
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From: cold & windy
and one thing i just realized (based on lionel's explanation) is that why does my system operate normally when i'm running a relay harness without a resistor - even with halogen bulbs? i understand the current flow concept he described, but by that explanation - since my factory low beam signal is only triggering the relay instead of bearing the load of the lamps themselves (or in y'all's case, the ballasts) - my buckets should stay up until i flash the high beams, too, right?
let me back up & give details on my current setup:
i swapped the factory headlight housings for the ACA projectors which use stock halogen 9005 high beams and halogen H9 65W low beams. due to the extra current draw from the H9s, they include a relay harness to protect the factory wiring (the same kind of harness used in HID applications to pull steady battery power to the ballasts - using the factory low beam plug as a relay trigger).
my lights work the same as they did from the factory with the exception of having the 4-high mod incorporated into the relay harness. shouldn't i also be experiencing the same low beam non-retraction issue?
this has me curious now...
let me back up & give details on my current setup:
i swapped the factory headlight housings for the ACA projectors which use stock halogen 9005 high beams and halogen H9 65W low beams. due to the extra current draw from the H9s, they include a relay harness to protect the factory wiring (the same kind of harness used in HID applications to pull steady battery power to the ballasts - using the factory low beam plug as a relay trigger).
my lights work the same as they did from the factory with the exception of having the 4-high mod incorporated into the relay harness. shouldn't i also be experiencing the same low beam non-retraction issue?
this has me curious now...
Race Director
Joined: Apr 2007
Posts: 11,150
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From: South Western Ontario
Mine works fine with the relay coil as the load too. The load doesn't have to be anywhere close to 55W. The car just needs a small amout of load on the selected circuit to make the lights go down. You could unplug the headlights and the little blue light is enough load to make the lights go down when the high beams are selected. The thing is that for some people the coil just isn't quite enough load.
5th Gear
Joined: Dec 2012
Posts: 5
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From: Dayton OHIO
Here is my 2 cents. I installed HID lights for low beam only. I work 3rd shift so I drive to work in the dark and home in the dark. 99% of my driving is low beam. So I did not go to the expense of installing high beams.
After installing the HID, I also noticed the lights would not go down. The cheap fix is exactly what "alxltd1" said. I turn off my head lights, then select high beam. Been doing this for 5 years. Works every time.
After installing the HID, I also noticed the lights would not go down. The cheap fix is exactly what "alxltd1" said. I turn off my head lights, then select high beam. Been doing this for 5 years. Works every time.
Advanced
Joined: Dec 2007
Posts: 82
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From: Lakewood Wa
Great info about the resistor for HID low beam lights. Not all C-5 behave the same. When i had the HID system I also ran it with a relay and had to try various things to make my light retract properly. One simple solution was to install a small light [use a side marker light for example ] and connect it on the passenger side lowbeam factory harness. I know this sound a little bit cheesy but it is cheap and truly works while the light reconize it as being 55w. By the way I went with George Argels V-2 Cannon fixed lights From Radioflyer Innovations which was the best investment I made and totally trouble free.