C7 Coupe Interior Storage lighting Fuse ?

[SharkBait]

Hi All need some help,
I was installing LED lights to replace the stock oem version and I blew the fuse accidental as I had a none plastic tool. Didn't think much of it until I tried to find the fuse to replace. Apparently this is top secret as I cannot find out which fuse it is. I believe it would be an AUX fuse but I check all of those and they were good. None of the interior lights shown up in the two fuse block listings. The license plate lights work along with everything else. I tested many of the low amp fuses and 10 amp fuses all working.

So that being said anyone know what fuse this may be? "two rear interior trunk lights"

 

[theboss]

Regular bulb dont have polarity but led light have, did you try to turn the bulb? can you show a picture of the oem bulb? I am pretty sure there is not a fuse just for that bulb

 

[theboss]

Are talking about the lights in the trunk? most of the interior lightning is powered by the BCM (body control module) who is powered by 3 10 amps fuses in the fuse block under the hood, fuse bcm5, bcm6 and bcm7 . bcm 7 is only on automatic cars. There is another fuse block in the floor on the trunk, fuse bcm1, its also for bcm power.

 

[cdnrx1]

As stated, that segment of the interior lighting is controlled by CANBUS through the BCM so you're not likely to find a blown fuse.

First thing to do, if you have not already done so, is to reinstall the original bulbs to see if they work. If they don't work, disconnect the negative battery cable for 20 - 30 minutes to reset the ECM / BCM. Reconnect, index your power windows, check the stock bulbs again. If they work then you know that the circuit is okay. I suspect that they will work and that the problem may be one of the following:

- incorrect LED bulb polarity, as stated by theboss.
- incompatible LED's, current draw is too low, confusing the CANBUS.
- make sure that the interior light circuit is not timed out, approximately 10 minutes.

Once you've done all of these checks and, hopefully, solved the problem, it's always a good idea to disconnect the negative battery cable while performing any electrical work.

Give these things a try and let us know how it goes.

Best regards
Ross

 

[SharkBait]

Hi All
Thanks for the information this is excellent feedback!
I had tried the original bulbs and I have tried to reverse the LED's. One did work when I first worked on them and then I shorted the terminals on the second one unfortunately.

I will try resetting and trouble shoot accordingly and will give you feedback once completed. Thanks again for the information!

Thank You
Charles

 

[YFCvii]

I had no issue installing leds on both my c7's.
Sourced brand name bulbs at Napa and they were a simple/careful switch-out.
Curious where you sourced your bulbs as I have people asking me when they
notice the white light within the interiors.
Your experience is something I would not have anticipated
and will have to mention it now. Yoikes

 

[SharkBait]

Hi All,
Ok, I have had successfully trouble shot the problem using your combined thoughts.

• 1st I have the hatched close to ensure timers were all reset, thinking that there was possible pwr at the lighting sockets.
• I used your idea to re use the old light bulbs ( as per Ross's suggestion) They lit up so I knew I had power and everything in the circuitry was working fine. Great !
• Took one incandescent OEM light bulb out and replaced it with the T10 LED and it work, lucky try with the polarity. ( I knew about the polarity before, however frustration got the better of me)
• While power was on I was careful and changed the 2nd OEM Light bulb and replaced with the T10, wrong polarity but no short, flipped around carefully with the right tool this time (non conductive) and it lit up and now all is well in C7 land.

Gentlemen,
Thank you for let me share my pain. I just needed a little direct to get this MOD done. You all helped immensely thank you for taking your time. It was a little hard to believe there was no fuse, I guess I am a little old school in that regard. Hopefully this will help others now that run into this situation. I will be tackling the License plates light next, but much more carefully. i will disconnect the neg battery terminal on that project.

Cheers everyone

Charles

 

[SharkBait]

Regular bulb dont have polarity but led light have, did you try to turn the bulb? can you show a picture of the oem bulb? I am pretty sure there is not a fuse just for that bulb

Hi there,
thanks for your input. You are correct there is no fuse. I order these LED bulbs from Amazon, then do work but not sure for how long we will see. I had made a few errors in trouble shooting the problem but you and the other got me on the right track to understand the system better and solve the problem. Thanks again

This is the amazon description of the Bulb....currently unavailable

194 168 w5w led bulb T10 175 2825 Wedge 24SMD 3014 Chips 6000K, 5Watts, White for Interior Car Dome Map lights, Door Courtesy License Plate Lights (Pack of 10)​

 

[SharkBait]

I had no issue installing leds on both my c7's.
Sourced brand name bulbs at Napa and they were a simple/careful switch-out.
Curious where you sourced your bulbs as I have people asking me when they
notice the white light within the interiors.
Your experience is something I would not have anticipated
and will have to mention it now. Yoikes

Hi Thanks for sharing, I have posted the bulbs and the description with the spec above. Being careful is really the trick. I should have know better, but the tool I used had a coating that I thought would be non-conductive. just need something plastic or wooden (chopstick) and I would not have had the problem and also remove the negative side of the battery...that would of solved all the problems, and is more safe all around.

Charles

 

[SharkBait]

Are talking about the lights in the trunk? most of the interior lightning is powered by the BCM (body control module) who is powered by 3 10 amps fuses in the fuse block under the hood, fuse bcm5, bcm6 and bcm7 . bcm 7 is only on automatic cars. There is another fuse block in the floor on the trunk, fuse bcm1, its also for bcm power.

Thanks again this was great to know the electrical system better. I was not aware of this before!

Charles

 

[theboss]

Happy to see everything work out now.

 

[SharkBait]

Changed out the License Lighting with LEDs this was much much easier, Again thanks for the help every. Cheers

 

[umpy]

Always be careful with ordering LED bulbs from sources unknown. As a supplier in the marine industry we always get challenged by " why are your marine LED bulbs so expensive" .
Some of these off shore bulbs run at high power creating a lot of light but also a lot of heat... and sometimes melting the light housings. Not good in a boat with a fire potential. We've seen customers walk back into dealers asking for a better bulb because of the heat from a cheap LED option.
Typical marine LED lights will run with a dummed down light ouput for safety.
So in your trunk area..... not a big deal as they won't be on too long. Your license plate light might be a different story. Go check it for heat after a while as it may melt the housing.
So the moral of the story might be to buy from a known source. May be more money at the outset. But Safe.
My 2 cents