Lights in the interior are only receiving half power?
03-01-2011, 05:30 AM
#51
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2004 E55, 1997 E320 "Sold"
yes, let's know.
fact is that the elctrical system in these cars (as in most modern cars) uses transistor switches, instead of relais, for a lot of minor functions (as it is the case for interior illumination).
As I already told you, these interior lights are NOT subject to a Fuse NOR to a relais. Therefore you cannot have burnt any of them. ***
They are instead driven by a transistor (which also can act as a dimmer).
The fact that you see something like 7Volts is worth nothing, it's a WRONG reading.
We had the same problem when fitting led taillights of the facelifted version: we could not get any 12Volts reading !! ... till we discovered that the electrical system does NOT work in continuous current but in Alternate Current .Proof that those 7 Volts you are reading is a fake reading is that they should suffice to light-on a bulb. it would not get the best of brightness but it should light on. but, as far as I understand from your words, it does not lights-on at all.
This does not happen because that's just a parasitic tension exiting from the transistor , with extremely weak current.
end of the story there are 2 scenarios:
Best: the CAN system detected the shorting and went into protection while impeding subsequent feeding of current. in this case a reset with SDS/STAR will solve the issue.
Worst: - your shorting burnt the transistor. In this case they will likely need to replace the whole SAM (while, in truth, it would just suffice to replace the bad transistor).
in any case this is an educating experience .. for us to know what can happen when toying with these cars without an appropriate engineering degree.
No more Fuses to save all DIYers out there
so, remain waiting !
***
from the scheme on top of page we know that E17/17 and E17/18 are rear footwell lights.
H2, for example, is the Horn.
While H2 is directly subject to a Relais and Fuse that you see on top, our E17s connect to pins 12 and 13 of SAM N10/1 but NO direct Fuse there... (even if the whole strip seems still subject to the previous relais. .. for the "Best" case scenario
)
just that weird symbol that I circled in green. guess what it stands for ...
)
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fact is that the elctrical system in these cars (as in most modern cars) uses transistor switches, instead of relais, for a lot of minor functions (as it is the case for interior illumination).
As I already told you, these interior lights are NOT subject to a Fuse NOR to a relais. Therefore you cannot have burnt any of them. ***
They are instead driven by a transistor (which also can act as a dimmer).
The fact that you see something like 7Volts is worth nothing, it's a WRONG reading.
We had the same problem when fitting led taillights of the facelifted version: we could not get any 12Volts reading !! ... till we discovered that the electrical system does NOT work in continuous current but in Alternate Current .Proof that those 7 Volts you are reading is a fake reading is that they should suffice to light-on a bulb. it would not get the best of brightness but it should light on. but, as far as I understand from your words, it does not lights-on at all.
This does not happen because that's just a parasitic tension exiting from the transistor , with extremely weak current.
end of the story there are 2 scenarios:
Best: the CAN system detected the shorting and went into protection while impeding subsequent feeding of current. in this case a reset with SDS/STAR will solve the issue.
Worst: - your shorting burnt the transistor. In this case they will likely need to replace the whole SAM (while, in truth, it would just suffice to replace the bad transistor).
in any case this is an educating experience .. for us to know what can happen when toying with these cars without an appropriate engineering degree.
No more Fuses to save all DIYers out there
so, remain waiting !
***
from the scheme on top of page we know that E17/17 and E17/18 are rear footwell lights.
H2, for example, is the Horn.
While H2 is directly subject to a Relais and Fuse that you see on top, our E17s connect to pins 12 and 13 of SAM N10/1 but NO direct Fuse there... (even if the whole strip seems still subject to the previous relais. .. for the "Best" case scenario
) just that weird symbol that I circled in green. guess what it stands for ...
)
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03-01-2011, 06:13 AM
#52
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you really don't want to use your warranty ?
if your Dad wants to play with silicium, tell him to check that green transistor above pins 12-13.
That N10/1 Sam has a bunch of sockets with 14 pins. it should be "L13".
03-01-2011, 06:24 AM
#53
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2004 E55, 1997 E320 "Sold"
I am going to use my warranty, but I just wanted to give him something to see so we would have a better idea of how to explain to the MB people what is going on. We are not going to touch that stuff lol.
03-01-2011, 06:34 AM
#54
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.. except it has 3 legs, it's not anything terrible
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OK, I pass on this ... going to look at TTM's injectors LOL
03-01-2011, 11:09 PM
#55
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Lol ^^^. I might have gotten one step closer to figuring out the problem. I was messing with the bulbs again, and decided to put the regular bulbs back in and see if they would work, and after removing one of the LED's while the other three were still in they all went out (no light), but when I put one of the regular bulbs in the other three LED's started to work normally at full power and brightness!
This tells me the car knows something is going on, but I do not understand why putting one regular bulb back in would make the others work? Is there a work around for this? Thanks
This tells me the car knows something is going on, but I do not understand why putting one regular bulb back in would make the others work? Is there a work around for this? Thanks
03-02-2011, 01:22 AM
#56
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03-02-2011, 02:27 AM
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2004 E55, 1997 E320 "Sold"
What do you think can be done to fix this snafoo? Resistors, but how do I add them into there and are we sure that will fool the car? The car will be at Mercedes in the morning so I will let them figure it out.
03-02-2011, 03:42 AM
#59
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Lol ^^^. I might have gotten one step closer to figuring out the problem. I was messing with the bulbs again, and decided to put the regular bulbs back in and see if they would work, and after removing one of the LED's while the other three were still in they all went out (no light), but when I put one of the regular bulbs in the other three LED's started to work normally at full power and brightness!
This tells me the car knows something is going on, but I do not understand why putting one regular bulb back in would make the others work? Is there a work around for this? Thanks
This tells me the car knows something is going on, but I do not understand why putting one regular bulb back in would make the others work? Is there a work around for this? Thanks
I would have guessed that you already removed ALL those non-oem lights ..
Happening of crazy things when replacing LED lights was already witnessed in my old thread about swapping taillights with the LED version.
good for you and .. for your warranty
03-29-2011, 08:48 AM
#60
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Crap...I was all excited about potentially swapping out the interiors for LED's...but this has scared me away a bit.
Mikey - any resolution?
Mikey - any resolution?
