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Hi,
Does anyone know what bulbs I use to change my vectra c 150, 1.9cdti 07 plate to white led.s,
Reverse bulbs ,And also wilL they flicker as the canbus system,
 

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Don't do it !

Without substantial wiring modifications, all exterior bulbs will strobe due to the canbus bulb check system if you use LED's. Not only that, while they might look "bright" the lighting power needed to actually use the lights to light up the darkness at night, simply won't be as good as a standard bulb.

Save your hard earned for more "useful" mods :D

The last thing you want is an excuse to be pulled over by the law for driving forward at night and yet showing strobing white lights at the rear.

HTH
 

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Without substantial wiring modifications, all exterior bulbs will strobe due to the canbus bulb check system if you use LED's. Not only that, while they might look "bright" the lighting power needed to actually use the lights to light up the darkness at night, simply won't be as good as a standard bulb.
Total rubbish I'm afraid. Yes modifications would need done to the wiring system but if you buy the right bulbs (ie not cheap ones) it's all included. Either way the wiring doesn't require "substantial modification". The can bus doesn't check to see if your using LED's, it checks so see if the bulbs are working by sending out small voltages. Since LED's use less power than standard bulbs that's why they pulse. That's also why a 12v LED is much brighter than a standard 12v halogen bulb. Less power is wasted as heat.
 

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If that is "Total rubbish I'm afraid" then I assume you can point to a source of non strobing LED reversing lights, where the light output is brighter than a standard bulb when used on a Vectra-C / Signum ?
 

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In my earlier reply, I was basing my response on some much researched, work on another forum with excellent results.

So, here you go, let the OP read this and make up his own mind.


"Of course, CREE LEDs do drain much more current than regular ones, but it will most pobably lead to the OBD strobing be VERY visible.


Still, those bulbs are interesting. But nothing will magically stop them from strobing.


Assuming their internal resistance would be lower, or most probably, the protection resistance will be lower, or even absent if they were really made to work under 12V, allowing for more current to flow trhough them and giving much more light, it would mostly help with OBD errors (maybe a higher value resistor in parallel would be enough to cancel errors, the same way as when wiring it across a relay coil, with the only effect to reducce heat - which is still appreciated).

But an LED is an LED. It has no inertia an is very sensitive to the least voltage, so it will always flash whenever the checking voltage will be applied, unless you asdd some delaying or low pass filtering device.

So in conclusion,

- It's very bright and very white, which is good
- It probably can work with a hng igher value resistor than usual to fool the OBD and cancel errors, which is good as well
- You still need a low pass filter, using either a relay or a capacitor and resistor cell to prevent the check voltage to flash the bulb.



One word about the resistor you linked.

Frst of all, "5W" means nothing for our use. It's only the maximum power it can handle before burning.

What we need is its resistance express in ohms. We care a f.ck about its power alone.

In the case of a 5W sidelight bulb under 12V, this means the OBD is looking for a 12²/5 ) 28.8 ohms filament. Actually, you can double this value and still get no error, as the OBD is tolerant enough, so a 50 ohms resistor would be OK, with the huge dvantage to heat much less. In fact, we could even use a 2.5 W resistor, but to keep some security margin, we'll stick with 5W.

When using a relay to cancel the strobing, the coil has a low resistance already. Not enough to foool the OBD alone, but quite low already (around 80 ohms), so wiring an additional 150 ohms resistor gives a combined resistance around the 50 ohms we're looking for : remember when combining resistors in parallel, you add their inverses : R total = 1 / ((1/R1) + (1/R2))

But for reverse lights, we need to simulate a 21 W bulb, meaning the OBD will be looking for a 12²/21 = 6.86 ohms filament. Now this is no joke. 21W bulbs do heat a LOT, and so will our anti-error resistor. There we can't use random values, or we'll melt our tail lights.

What wil probably help will be the 12V CREE LED bulbs will probably have a much lower resistance than the usual ordinary LEDs + protection resistor assembly (that has a very high internal resistance). We could use this to our advantage, the same way we used the relay coil own resistance.

However, this means we have to know that value, and I don't know it. You'll have to buy the bulbs first and check the resistance across the poles using an ohmmeter. Be careful to use the correct polarity, or you'll get an infinite value (after all, LEDs are still diodes and allow the current to flow only one way).

If the measured value is low enough, then maybe we'll be able to use higher value than the damn 7 ohms for our anti-error resistor. As the problem is, such a low value resistor will heat like a toaster !!! In theory, a 25W model should be enough, but maybe you'd better select a 50, or even 100W model, so it would stay relatively cool...

However, it still doesn't address the strobing. Since the bulb you linked doesn't look like you could easily insert a capacitor inside, and it may even not have the necessary resistor in series onboard, we're obviously on to a 100% external solution.

There I honestly think the relay solution will stay the simpler.

Now at least we can calculate the needed resistor to build the anti-error value, as we do know the relay coil resistance...

It gives 1 / R total = (1/R coil) + (1/R)
=> 1/R = (1/Rt) - (1/Rc)
=> R = 1 / ((1/Rt) - (1/Rc))

OK, so we know Rc = 80 ohms (relay coil resistance) and Rt = 7 ohms to simulate a 21W bulb filament. From experience from the sidelights, we can probably double the value, so let's take... Well, 12 ohms so we should be inside the tolerance range.

So we should add a resistor across the relay coil poles whose value should be R = 1 / ((1/12)-(1/80)) = 14 ohms

As you can see, the problem with such low values is the 80 ohms coil almots doesn't count...


So we almost need a... 21 W bulb across the relay coil (still and option, if you can avoid stray light inside your boot ^^), or a 14 to 15 ohms wirewound resistor, if you can find some.

Now let's calculate the needed power to avoid catching fire in the boot...


Of course, 21 W is probably around the good value, but you'll be able to fry a steak on it, so let's find something better.

Under 12V, a 15 ohms resistor will dissipate 12²/15 = 9.6W : still much better than 21W...

So using a 15 ohms resistoir across the relay coil, I avise you use a 25 to 50W wirewound model, that would hopefully stay cool enough.

Once again, using the OBD tolerance and the relay coil, we have been able to use a higher resistance, less heating resistor than theorically necessary.


If I have some time, I'll do some tests with my reverse lights to get sure 15 ohms would be enough to cheat the OBD.


Note that you could also select a lower value (10 to 12 ohms) resistor, selecting a 50W wirewound model, followed by a small resistor in series, then a capacitor in parallel.

You would get something less bulky than a relay, and you could solder all this directly to the tail lights bulb holders.


Since the anti-error resistor value will have to be lower, you'll select a higher power one so it stays cooler if possible.

Remember the power value is only the limit before it burns. I still don't understand why most sellers only give this value, as it's totally irrelevant to chose the correct model : you need to know the resistance, not the power. Well at least, not just the power, as you still have to select a model that's powerful enough to resist the heat. ^^ "


I'm quoting a reply from an electronics wizzard on the workings of the Vectra-C electronics here :D

I hope that this explains my initial response to the OP adequately.

Woody :D
 

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Don't do it !

Without substantial wiring modifications, all exterior bulbs will strobe due to the canbus bulb check system if you use LED's. Not only that, while they might look "bright" the lighting power needed to actually use the lights to light up the darkness at night, simply won't be as good as a standard bulb.

Save your hard earned for more "useful" mods :D

The last thing you want is an excuse to be pulled over by the law for driving forward at night and yet showing strobing white lights at the rear.

HTH
If he buys canbus bulbs, that won't be an issue.
The flickering effect happens on herman cars.
Its easy to put right on any car. Just a resistor is required..
You sound like an old woman.
Im fact proper led smd cree led projector canbus bulbs are bright and white. Hence contrary to what you claim and are brighter.
 

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Hi,
Does anyone know what bulbs I use to change my vectra c 150, 1.9cdti 07 plate to white led.s,
Reverse bulbs ,And also wilL they flicker as the canbus system,
Pop the original bulb out and read the info.
Buy canbus ready bulbs. Ideally a ceramic. Im unsire if your vectra take a t15 or a t20. It may takebthe push and twist bulbs.
You may need a decent resistor to cancel out the flickering..
 

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In my earlier reply, I was basing my response on some much researched, work on another forum with excellent results.

So, here you go, let the OP read this and make up his own mind.


"Of course, CREE LEDs do drain much more current than regular ones, but it will most pobably lead to the OBD strobing be VERY visible.


Still, those bulbs are interesting. But nothing will magically stop them from strobing.


Assuming their internal resistance would be lower, or most probably, the protection resistance will be lower, or even absent if they were really made to work under 12V, allowing for more current to flow trhough them and giving much more light, it would mostly help with OBD errors (maybe a higher value resistor in parallel would be enough to cancel errors, the same way as when wiring it across a relay coil, with the only effect to reducce heat - which is still appreciated).

But an LED is an LED. It has no inertia an is very sensitive to the least voltage, so it will always flash whenever the checking voltage will be applied, unless you asdd some delaying or low pass filtering device.

So in conclusion,

- It's very bright and very white, which is good
- It probably can work with a hng igher value resistor than usual to fool the OBD and cancel errors, which is good as well
- You still need a low pass filter, using either a relay or a capacitor and resistor cell to prevent the check voltage to flash the bulb.



One word about the resistor you linked.

Frst of all, "5W" means nothing for our use. It's only the maximum power it can handle before burning.

What we need is its resistance express in ohms. We care a f.ck about its power alone.

In the case of a 5W sidelight bulb under 12V, this means the OBD is looking for a 12²/5 ) 28.8 ohms filament. Actually, you can double this value and still get no error, as the OBD is tolerant enough, so a 50 ohms resistor would be OK, with the huge dvantage to heat much less. In fact, we could even use a 2.5 W resistor, but to keep some security margin, we'll stick with 5W.

When using a relay to cancel the strobing, the coil has a low resistance already. Not enough to foool the OBD alone, but quite low already (around 80 ohms), so wiring an additional 150 ohms resistor gives a combined resistance around the 50 ohms we're looking for : remember when combining resistors in parallel, you add their inverses : R total = 1 / ((1/R1) + (1/R2))

But for reverse lights, we need to simulate a 21 W bulb, meaning the OBD will be looking for a 12²/21 = 6.86 ohms filament. Now this is no joke. 21W bulbs do heat a LOT, and so will our anti-error resistor. There we can't use random values, or we'll melt our tail lights.

What wil probably help will be the 12V CREE LED bulbs will probably have a much lower resistance than the usual ordinary LEDs + protection resistor assembly (that has a very high internal resistance). We could use this to our advantage, the same way we used the relay coil own resistance.

However, this means we have to know that value, and I don't know it. You'll have to buy the bulbs first and check the resistance across the poles using an ohmmeter. Be careful to use the correct polarity, or you'll get an infinite value (after all, LEDs are still diodes and allow the current to flow only one way).

If the measured value is low enough, then maybe we'll be able to use higher value than the damn 7 ohms for our anti-error resistor. As the problem is, such a low value resistor will heat like a toaster !!! In theory, a 25W model should be enough, but maybe you'd better select a 50, or even 100W model, so it would stay relatively cool...

However, it still doesn't address the strobing. Since the bulb you linked doesn't look like you could easily insert a capacitor inside, and it may even not have the necessary resistor in series onboard, we're obviously on to a 100% external solution.

There I honestly think the relay solution will stay the simpler.

Now at least we can calculate the needed resistor to build the anti-error value, as we do know the relay coil resistance...

It gives 1 / R total = (1/R coil) + (1/R)
=> 1/R = (1/Rt) - (1/Rc)
=> R = 1 / ((1/Rt) - (1/Rc))

OK, so we know Rc = 80 ohms (relay coil resistance) and Rt = 7 ohms to simulate a 21W bulb filament. From experience from the sidelights, we can probably double the value, so let's take... Well, 12 ohms so we should be inside the tolerance range.

So we should add a resistor across the relay coil poles whose value should be R = 1 / ((1/12)-(1/80)) = 14 ohms

As you can see, the problem with such low values is the 80 ohms coil almots doesn't count...


So we almost need a... 21 W bulb across the relay coil (still and option, if you can avoid stray light inside your boot ^^), or a 14 to 15 ohms wirewound resistor, if you can find some.

Now let's calculate the needed power to avoid catching fire in the boot...


Of course, 21 W is probably around the good value, but you'll be able to fry a steak on it, so let's find something better.

Under 12V, a 15 ohms resistor will dissipate 12²/15 = 9.6W : still much better than 21W...

So using a 15 ohms resistoir across the relay coil, I avise you use a 25 to 50W wirewound model, that would hopefully stay cool enough.

Once again, using the OBD tolerance and the relay coil, we have been able to use a higher resistance, less heating resistor than theorically necessary.


If I have some time, I'll do some tests with my reverse lights to get sure 15 ohms would be enough to cheat the OBD.


Note that you could also select a lower value (10 to 12 ohms) resistor, selecting a 50W wirewound model, followed by a small resistor in series, then a capacitor in parallel.

You would get something less bulky than a relay, and you could solder all this directly to the tail lights bulb holders.


Since the anti-error resistor value will have to be lower, you'll select a higher power one so it stays cooler if possible.

Remember the power value is only the limit before it burns. I still don't understand why most sellers only give this value, as it's totally irrelevant to chose the correct model : you need to know the resistance, not the power. Well at least, not just the power, as you still have to select a model that's powerful enough to resist the heat. ^^ "


I'm quoting a reply from an electronics wizzard on the workings of the Vectra-C electronics here :D

I hope that this explains my initial response to the OP adequately.

Woody :D
You've way over complicated things there. Those resistors are from osram. They know what they are doing. If they say it's stops can bus errors on 5w or 21w systems then they do. As for the flickering, this is where you need to get the right bulbs. Yes what you've just said will likely work (to be honest I didn't read it all) but, it's so much simpler getting some flicker free bulbs. I'm not saying the ones I linked are flicker free but there's plenty of them out there.
 
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