Christi@n

I've just purchased bulbs plasma led, both For tailight and front parking light.
I've no problems with rear light led bulbs only, they are working properly, but once I've got front parking led bulbs in socket, at this point all the system works with parking light turned off only, that's all four corner blinker work properly.

Though When I turn on parking light and then blinker, blinker is stucked, no flashing

So i've re-installed classic 1157 incandescent bulb for front, and then it works. I've already in an electromechanical flasher...


Any idea?

Bluezman

Hi. It is a bit tough to follow your description of what's happening, but I am sure the problem you have is caused by the difference in resistance from the standard filament bulbs vs. LED.

LED's draw very low current and will cause the light controller in your Corvette to react in odd ways. Why Chevrolet engineers designed our cars that way is irrelevant at this point, but they had good reason for it.

The only options you have are to add resistors to the light circuits with the LED bulbs, buy LED bulbs with resistors built into the lamps themselves, or replace the lighting relays with resistance-matching relays. I'm sure all of that is available at local auto parts stores and tuner shops. You can find everything online as well. It is a common problem.

It is easy to fix but can make you feel like your car is possessed. It's all about matching the resistance of the original lamps at each location. I hope this helps.

Christi@n

To be more clear, long story short

With 4 led bulbs installed (4 red tail bulbs) car works, when I put in 5th and 6th led bulbs (two Amber front parking lights ) car won't works.

Bluezman

Ok. I understand. Still, I have a great deal of experience with these issues. The problem is centered around the disparity between resistance values. If you add up the total resistance of each controlled circuit, and match that, the LED's will work perfectly. Anything else will cause problems.

If you forget the bulbs you have and buy LED's that have resistors to match their incandescent counterparts, the problem will be nonexistent (until you burn a resistor).

Christi@n

Ok, but I think you forgot a part of the story:

With 4 red tail led in and 5th and 6th front amber led in, car still properly works, as long as lights (parking and headlamps) are off.

In this case the blinker works right

Bluezman

The thing is, our Corvettes have a control module that looks at various resistances of each controlled circuit. It's different than the resistance of a circuit overall - or, in other words, the entire added resistance of every lamp on a particular fuse, for example. The body control module compares the resistance of the controlled circuits and reacts based on the added or divided effects of each circuit. The circuits react differently whether they are compared in series or parallel. In series, resistance increases. In parallel, resistance decreases.

So it is very complicated to "out smart" the controller because it is always looking for these values. If it sees something different, odd things happen to the lighting. It is much different than what you'd expect and can make a person feel like they are losing their mind.

The truth of the matter is, using LED's that are corrected for incandescent resistance is the easiest way to keep the system working like it should (LED's with +/- 10% similar resistance to 1157 bulb for example). To make it work any other way would require a person to change the control modules altogether. It isn't a terrible idea but you'd loose the higher-level functionality of the car. I am certain that a person could bypass most or all of the electronics on a Corvette using basic relay logic. It would dumb down the system but might be more reliable. I know that GM engineered these various control modules to participate in the general control of the vehicle, diagnostics, and the VATS protocols. It's irritating now as the older control systems seem quite clunky. But at the time, it was genius. You are running against this stuff when you change out certain parts of the car. The clearance, brake, and turn signal lamps are an example of this.

Christi@n

I will contact the bulbs dealer tomorrow (synetic usa) and ask them about this bulbs....

though i'm not sure that i'm not using led with resistance correction... They didn't recommended me a resistor, when bought bulbs

These bulbs are 1157 bulb type 2835 chip 12 smd led. These for front light

Bluezman

That's a good company and they sell good quality LED's. Some places sell garbage, which adds to the problem generally.

I just looked on their website to find the LED's you purchased but couldn't find them listed. I'm sure I just missed them. But I saw that they do offer resistors to pair with the lamps.

I was at a local auto parts store and saw that they sell resistors in the section where they have the LED's displayed. Its nice that they are becoming more common. It looks like you are in Italy so I don't know what is available there. I'm sure everything is set up about the same as it is in the US though. You'd probably find everything you need right there.

I'm confident the resistors will end your problem but if you need anything else, just let me know.

RWDsmoke

There is a flasher available that is made to solve this problem. It has a separate ground wire so it doesn't rely on the load of the circuit to control the flasher. I haven't tried it yet but a friend told me it worked for his car.

Christi@n

Do you know what is would be?

I've already in a sort of this flasher... That's an electromechanical type...

It makes the typical tic-tac sound when turn on blinker..... The stock electronic type is almost completely quiet...

I have heard that electromechanical is the right one for this problem but it is not my case

JimLentz

You don't want the mechanical type as they require a certain load to work. You want one like this.

Christi@n

I can easy go with that? Mount it and anymore problems?
Need to connect the ground?

Do you know?

JimLentz

Check the link for flasher selection guide to be sure. The one I linked is good for up to 30 W and you don't need a ground wire.

Christi@n

Thank you Jim, i will get tht flasher.....

Christi@n

Just spoken with dealer they said me

"Our LED bulbs have internal driver to stabilize the current (resistor on board; if that's what you meant by resistance correction?)"

Is this the resistance correction?

Christi@n

I've just received the flashers...

I've them in hands ( one for turn one for hazards)

Just they seems a little bit too big, compared to the stock one...
Does it fit properly on that clips?

P.s, ruler is cm

Christi@n

I don't know why i'm never be able to upload more than one shot per time

Cathul

It will fit, but not work. I tried them, too. You need an electonic-mechanical flasher, the pure electronical flasher wont work (at least in my car they didn't).

EL12 will work as well as EF32.

Tried both and both work. CF12ANL wont work.

Christi@n

The el12 Is that one i've in at the momento and it won't works

Christi@n

Also cf12anl, they say is not a pure electronical, it is instead an electronical for led

https://www.superbrightleds.com/more...c-flasher/781/