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HAPPY NEW YEAR
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Discussion Starter #1
So guys I ordered my hvac led's they are the (4) 74 small type bulb. I had all the regular fillament bulbs in and on...I went to remove the first one and put the led in when It blew and had a small cloud of smoke along with a burnt smell...The fuse in the door for the hvac controls is fine. They are all strung together by two yellow/black wires and then plug into a circuit board behind the hvac controls. Once they blew ALL of them went out and this was when I tried to install one LED and the rest were regular. I tried putting all the regular bulbs back in and now they will not come on at all.

Cliffs
Tried to install and led
blew all 4 hvac bulbs
hvac fuse did not blow
all 4 hvac bulbs will not come on at all now, even with the regular bulbs in there.

Any help, greatly appreciated. I'm going to try and upload the pics of the connectors and where they go into the circuit board off my phone. Hopefully that works. Any tip, suggestion, or any help at all is greatly appreciated. I have no idea where to go from here.
 

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HAPPY NEW YEAR
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3,599 Posts
Discussion Starter #2
Ok. All 4 bulbs and connectors are strung together by that yellow/black wire and then in the second pic on the right side you can see where the yellow/black wire wires into that connector on the circuit board directly behind the hvac controls. I'm at a loss on where to go from here. I hope there is someone that may be able to shed some light on this situation.



sent from HTC evo
 

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kissin hands shakin babie
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6,529 Posts
to clarify you put 4 good regular bulbs in, or you put the same 4 that were blown out in?

and next time i would unhook the bat, or atleast pull the fuse before playing with something eletrical.
 

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HAPPY NEW YEAR
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Discussion Starter #4
I haven't replaced all of them yet at all :hmm: I do have 4 LED ones that are good lying there but I don't know if that'll help anything. I don't have 4 good regular ones lying around though.
 

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kissin hands shakin babie
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they are wired in series with eachother, so if one burns out, the circut is broken, and the other wont light up,

personally, i would get 4 good regular bulbs and put them in and make sure that the harness works before putting the led's in. this is because with leds sometimes you have to flip them around to make sure they light up.
 

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HAPPY NEW YEAR
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Discussion Starter #6
they are wired in series with eachother, so if one burns out, the circut is broken, and the other wont light up,
Okay. That's exactly what happened. The very first one I tried to put the LED in and it blew and the rest went out. I tried putting all good LED's in and no dice. If I go buy new regular 74's and then they don't work where do I go from there? I thought they smoke and burning smell was pretty odd though.

Another thing that's odd is last week I bought all new twistlocks for the back of my gauge cluster with regular fillament 194's and they all worked perfectly. Last night I had 6 194's ordered and so It took pliers to get the regular 194's out of the new twistlocks, then I put all the new LED 194's in with the brand spanking new twist locks and the guages won't light up at all! Not even a flicker. I tried taking them all out and flipping them and nothing! I even just went out and tried to put the regular 194's back into the twist locks and it still does not work! This is leading me to think I blew something that controls all the guage lights and the HVAC controls. Odd thing is the emergency brake light still works and the little orange light for my gear shifter, but basically it all worked perfect and then I tried LED's and none of it will work even if I go back to regular bulbs now....I'm at a loss here.
 

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kissin hands shakin babie
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you sure you didnt hit the ilumination dial next to the headlight switch down and turn them all down?
 

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HAPPY NEW YEAR
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Discussion Starter #9
you sure you didnt hit the ilumination dial next to the headlight switch down and turn them all down?
I've done that before so I checked a million times to make sure that wasn't it. I just think it's odd.. All brand new twist locks and LED bulbs and not even a flicker from one of the 6 bulbs...I don't get it. It's as if a fuse that controls both the guages and hvac is burnt out...The other thing is I tried installing the gauge lights before the hvac lights ever even blew, and nothing blew with the guage lights they just didn't come on at all....

do you have a multi meter or a test light?
I have plenty of lights I can test. Can't I just use a 9v battery?
 

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Your HID Preferred Vendor
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a test light is for testing electrical circuits......... we know the circuit is missing something.... its either power or ground. you'll never be able to figure out which if you dont have the tools to diagnose it. you can make a test light if you really need to, but buying one is NOT bad idea
 

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HAPPY NEW YEAR
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Discussion Starter #11
a test light is for testing electrical circuits......... we know the circuit is missing something.... its either power or ground. you'll never be able to figure out which if you dont have the tools to diagnose it. you can make a test light if you really need to, but buying one is NOT bad idea
So it's either missing power or ground :think: Everything is already wired up and good but I have no idea exactly what blew. I know the smoke came from the first little lock in for the bulb that I tried to put in. I'm having an electrical guru buddy look @ this in about an hour. As you see I'm terrible with electrical stuff
 

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HAPPY NEW YEAR
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Discussion Starter #13
hahaha no everyone else it works for but this my luck type shit.

Does ANYONE know what could be the problem with a puff of smoke and a burnt smell if it's not the fuse? Am I going to have to rewire all of this? What?
 

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HAPPY NEW YEAR
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Discussion Starter #14
Okay guys so its not a fuse or relay and I even got another cluster and that didn't work. Everyone tells me I fried something in the HVAC but noone can tell me what the next step is. Everything works except the 6 lights in the cluster and the 4 lights in the hvac..someone please help.

I even tried putting new regular bulbs in the hvac and putting reg bulbs back in the cluster and still nothing....again, please lead me in the right direction on where to go from here

sent from HTC evo
 
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