Replacing VF reading lamp globes with LED’s

[mwb235]

I bought these to replace the factory globes in a Magnum. All worked, no problems and no codes.

https://www.ebay.com.au/itm/10PCS-C...HITE-/322075524546?hash=item4afd327dc2&_uhb=1

Imoengnr does your Magnum have reading lamps? I just had a look at that ebay listing and it says the power is 2.1W. I thought I needed 5W so they turn on and off as per stooge’s post above? I’m confused.

 

[TTubrag]

Yep, As mentioned, you'll need to add load resistors or Canbus compliant LED T10's to beat the Canbus system in the car. Only applies for the map lights. The other interior 'dome' lights should be ok. VF is same as VE in this regard apparently.

https://www.autoinstruct.com.au/manufacturer/holden/ve-commodore/changing-interior-light-globes/

Check your eBay T10 LED's carefully though. The stock internal bulbs only throw about 40 lumens of light I think at about 3200 kelvin. If you fit an LED that throws out 200-300 lumen at 6500 kelvin, it's going to be blindingly bright and have a very bluish colour, which can get tiring after a while.

I like the Philips 4000k interior T10 LEDs for this application. Only 45 lumen but plenty white and bright enough, while not being tiring. Quality product too... not a hit and miss eBay jobbie.

https://www.powerbulbs.com/au/product/philips-x-treme-ultinon-led-w5w-t10-4000k

 

[lmoengnr]

Imoengnr does your Magnum have reading lamps? I just had a look at that ebay listing and it says the power is 2.1W. I thought I needed 5W so they turn on and off as per stooge’s post above? I’m confused.

Yes, just front ones, I think these have load resistors on the circuit boards.

 

[mwb235]

Yep, As mentioned, you'll need to add load resistors or Canbus compliant LED T10's to beat the Canbus system in the car. Only applies for the map lights. The other interior 'dome' lights should be ok. VF is same as VE in this regard apparently.

https://www.autoinstruct.com.au/manufacturer/holden/ve-commodore/changing-interior-light-globes/

Check your eBay T10 LED's carefully though. The stock internal bulbs only throw about 40 lumens of light I think at about 3200 kelvin. If you fit an LED that throws out 200-300 lumen at 6500 kelvin, it's going to be blindingly bright and have a very bluish colour, which can get tiring after a while.

I like the Philips 4000k interior T10 LEDs for this application. Only 45 lumen but plenty white and bright enough, while not being tiring. Quality product too... not a hit and miss eBay jobbie.

https://www.powerbulbs.com/au/product/philips-x-treme-ultinon-led-w5w-t10-4000k

Thanks for that! I’ll have to look at those too. Although I note in the specifications for the Powerbulbs LED’s it says they are only 1W? Maybe wattage isn’t the only determinant?

Yes, just front ones, I think these have load resistors on the circuit boards.

Hmmm maybe 2.1V is enough power. I think all the various LED’s i have tried so far are 1W or less so that might explain it. I’ve already ordered the 5W LED’s, but I might order some of the ones you got too since they’re cheap plus I’d get them before the others as they’re an Oz seller.

 

[Ausroamer]

I'm no expert in how these systems work, but as per above comments, it's likely a load sensing circuit. A 5W LED will be much brighter than a 5W incandescent globe, so ideally you want a low watt LED coupled with a load of some form (ie resistor). If you use a 1W LED globe, then you need approx a 4W additional load. Using the formula P=VA, then 4=12xA. The required additional load is about 0.33Amps. Using the formula V=IR, then 12=0.33xR which equates to a 36 Ohm resistor.
Caveat: I'm not electronic expert, but this seems like it would work to me and I hope it helps. You may also be able to get LED globes designed to use the same current as an equivalent incandescent globe, but I've never looked.

 

[HoldenCalaisV]

View attachment 199028

I fitted the Konik T10's and they work perfectly fine on the rear light housing for all 3 light functions.

https://www.ebay.com.au/itm/KONIK-K...067729&hash=item1a2bc29d8c:g:HuEAAOSwR29ZHn1o


May I ask how did you disassemble the front light housing with the sunroof?

 

[greenacc]

The problem with LEDs in these type of circuits is the low Resistance, not the low watts. Adding a resistor like Ausroamer said would solve the problem but be a pain in the bum to install and you end up butchering your wiring. Sounds like the LED globes don't have enough resistance for the light circuit to detect the lights are on.
This kind of explains it.
https://www.google.com.au/amp/s/tin...riving-an-led-with-or-without-a-resistor/amp/

 

[mwb235]

Ok thanks folks for all the helpful info. I obviously have a lot to learn about electronics!

 

[mwb235]

May I ask how did you disassemble the front light housing with the sunroof?

The whole light housing just pops out. Gently pull on front edge (closest to windscreen) with fingernails under edge of plastic. Then just three small wiring plugs to disconnect. That link from Ttubrag above showing how to do it in the VE (same light housing) shows this.

 

[mwb235]

I just thought of something (it can happen!). I remembered I had recently bought these LED’s to put in the small courtesy lamps at the bottom of each of the four doors (i.e. lamps that face the ground). I used these as they only have LED’s on one side rather than multi-directional, so they don’t fill the door cavity with excess light. They are 2W, 6000K, 120 lumens, and have a load resistor of some sort.

So just as a test I tried them in my reading lights, and voilà! They work perfectly and i can turn them on and off. Whacko! So I will try some of the other LED’s others have suggested above and I’ll be back in business!

Thankfully some of us (i.e. not me) know what we’re doing!