Jump to content
SAU Community

Recommended Posts

Hi all

I have a 34 GTT and have replaced the bulbs behind the air con LCD display with LEDs. I bought these LEDs from an overseas seller who modified the stock bulb twist lock bases and put in a LED + resistor.

Weird thing is that 1 of the 3 LEDs sometimes works and sometimes doesnt.

3 days ago it didnt work when I started the car up in the morning, when i started it in the afternoon it was fine.

2 days ago, same thing again, didnt work in the morning but in the afternoon after work it worked fine.

Yesterday, didnt work in the morning, worked in the afternoon. Later on during the night it didnt light up again so I pulled it out, all looks to be well. The contacts, LED and resistor look okay (i think) so put it back in, and it works fine. I dont think its a loose connection because how can it work when I park my car at night, then not work when I start it in the morning.

Anyone have any ideas? I would get a new one but they arent cheap and take a while to get over here, just wanted to figure out what the deal is, quite annoying hahah

Thanks

Your LED and resistor is getting too hot... I bet.

If you work out which resistor you need (in ohms), you'll probably also notice a "wattage" rating. The bigger, the more amperage it can handle. The more amperage it has to drop for the LED, the more it has to transfer energy into the form of heat.

The heat will make an LED work, not work, flicker... you name it.

For most 14v applications, a 1 watt resistor is MINIMUM, but i've encountered problems even with those! A 2watt would work, but they're HUGE!

Only workaround I can think of is to use two resistors per LED. One to drop the voltage, and one across the LED to drop the amperage. Theoretically, they will both share the load. 2x1watt = 2watt.

Yet to actually TRY this though. =-[

Edited by RANDY

Thanks Randy

Problem is they were hand made pre purchased items. Strange the other 2 in the exact same design are not having issues.

If heat is making it fail, I would;ve thought it wouldnt work in the morning and not the other way around. Ill swap the 2 working LEDs over to see if its a problem with the bulb or the connection on the circuit itself.

I think when the LED's get overheated, they are semi-dead. I've had 4 of them do the exact same thing to me, and then I went back to the drawing board and started measuring the temperature of the resistors with my multimeter.

14v down to 3.3v, at 100ma, using a 1/2watt resistor saw the temp go to about 80 degrees celcius within 30 seconds.

I'm using a 1 watt resistor now, and it gets to about 70 degrees. Obviously still too hot, because the globe assembly part has actually deformed from the heat, and those LED's are now stuffed.

My left-hand side doesn't work at all anymore, and the right-side flickers on and off.

Okay switched around the LED that I thought was broken with one that doesnt give me a problem at all.

Worked well for 2 days...until today.

The one originally with the problem is in a new spot and that is fine.

The one that never had a problem in the problem spot is not fine.

This leads me to think that its the actual connection spot and not the LED itself.

There are 3 spots for bulbs behind the LCD display, why would the first spot from the left sometimes work and sometimes not. e.g. park my car, leave it for 10 hours, come back, and it doesnt work anymore. This is frustrating.

I've returned the lights behind the LCD back to stock.

No problems yet (apart from the ugly light you get from incandescent bulbs). This morning it was fine.

If it continues to stay fine, what could it be? The circuit not liking the LEDs?

Stock bulbs still doing okay by the looks of things...what theeee??

LEDs broken? cant be because I switched them around and its always the same spot. Circuit can deal with the board perhaps?

I did see that one of the legs of the resistor for the LED was touching the actual resistor, does this cause a problem?

It's the contact being made on the track at the base, it may look OK, but the modified bulbs if treated to too much heat misalign the base giving intermittent contact.

This is why it's good practice to test all bulbs in situ before sending them out, just to check for any invisible defects.

The R34 A/C is prone to needing exact contacts with the rail, that's why I soldered directly to them.

So perhaps that one spot is prone to some extra heat, that is why no matter which LED I use (I believe they are all working okay), somehow the LEDs are getting faulted?

Strange why for 3-4 weeks there wasnt an issue at all.

Is there anything wrong with soldering the LEDs directly on? I am worried that I could permanently stuff up something, OR I wont be able to return it back to stock if I wanted to (ie. the copper contacts are ruined?)

Sorry, I jsut realised they ones you're talking about. I did the same thing as the guy, soldered them up and wrapped them around the base, as you would with a bulb.

It's the back lights for the buttons I soldered!

Hmm OK I've had no issues with the other ones, they went in extremely snug though, no possibility of them coming out without a screwdriver in the base slot.

Hahah cool cool. My LEDs which are in a twist lock base for the buttons are working 100%, no dramas there yet (fingers crossed)

But behind the LCD, the guy who gave me the LEDs in the twist lock base, those bases arent a perfect fit, they are actually smaller than the original bases, I think that is where my problem is.

Do you agree DAN? I am inclined to think so seeing as the stock bulbs in the stock bases are doing okay at the momment. Too bad they're almost an orange colour when viewed with the blue buttons.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Hey guys, Just want some advice on r34 GTT ac system. Since I’ve owned it, the ac compressor, doesn’t matter the set temperature or ambient temperature, runs for around 10 seconds then disengages the clutch, then re-engages everywhere 30 seconds or so and keeps repeating this.    is this normal?   I had it recharged today as it was slightly low and thought it would fix it but still does it. it cools fine in summer even prior to the recharge, except for the usual warmup when stopped or in traffic (still yet to wire overheat fan to on with ac)   any thoughts would be much appreciated 
    • To plug the hole. The engine plant may not have known whether the car it was going into had a gauge or not. It was a long time ago and the integrations might not have been fully modern. Or they might not have cared because the extra inventory and processes to save a few cents on the sender might have cost more anyway. But please tell me you are not still confusing the idea of a pressure gauge sender, and an oil pressure light switch. The switch will be out there. In a separate hole. Probably with only one wire running to it. Running the light.
    • Blower needs to go low on the exhaust side, displacing the AC and PS, which you have to decide whether you want to keep and how and where to relocate if you do. Electric option for PS is, at least, helpful. Sadly, there is no workable 12V electric AC of any value. Whilst the blower is the last compression step before the throttle, and so it might seem a good idea to have it near the inlet manifold (as mentioned above), you probably want it to go through an intercooler first, so, having it on the opposite side of the car facilitates that air flow path. The turbo discharges into the blower, so proximity of the turbo's compressor outlet to the blower's inlet is nice. But then you might want to intercool that too, before boosting it again....which would probably be a ball ache. Routing pipes out to the front and back could be a bit shit. If there was room for (at least) a small (but preferably larger) water to air core on that side, then that would probably be the best approach. I guess a reasonable alternative would be to locate the blower where the alternator is (more or less, associated with the inlet manifold, per Matt's thought), and somehow incorporate a water to air core into the manifold, sort of like they do for modern blown V8s. The big difference here though is that those V8s have only the one throttle (upstream the blower) and only the one compression step (the blower) and no need for too much in the way of bypass/blowoff valves. Whereas in a twin charged 6, you do need to think about one or two bypass valves associated with the 2 compressors and you would prefer to have the intercooling done before the air has to pass through the throttle. You'd like the throttle to work approx the same no matter what the compression is doing. But if it is located in hot air stream before a cooler, then sometimes the air will be real hot, sometimes it will be quite cool, and the throttle mapping/response will be quite different between those two cases. The throttle, if sized for hot air, would be too large for cold conditions. It's all a ball ache.
    • Package SC on exhaust side. Remote mount turbo. Still a fair bit of room when you get creative on the inlet side of the motor too. Especially if you can get really creative with the welding, and effectively build it into the bottom of the inlet manifold. Would definitely take some design work, and some trial and error, to make sure flow works well still! Might be easier to just start with the Nissan March though... All the work is already done for you...
    • I'll sit down and get a post together 😁
×
×
  • Create New...