I note from the dual battery wiring diagram that the connection from the system battery to the BCM is unfused so that if there is a short to ground (due to moisture) in the BCM then there is nothing to stop the max battery current flowing to the BCM - so I agree with the rational for your mod as in the event of a fault it will likely prevent further damage to the vehicle. Nice job.
Yes I caught that at the end, I was just concerned about the gauge of the wire. I’ll definitely carry out this work on mine. Love the site for the Merc so keep up the good work.
Hi, well I was all set to do the mod this weekend after flying home from work, my neighbour knocked this evening to say she thought she saw smoke at the back of my SL. Guess what...... Luckily I caught it before the car caught fire but the wiring, module and some carpet has melted. Obviously the car is now totaled, but I want to get the car off the road and in to my garage. How do I get the car out of park, and the steering lock off? Any clues?
Great job! You should try to get the car as original as possible - grille, removal of boot spoiler, etc. These are future classics! Give the steering wheel a go, its an easy job and will make the driving experience so much better.
Thanks, you are the first person to ever say remove the spoiler, the grille though I have had a few people say no but majority like it. The steering wheel I am looking at replacing with the wood combo, but may just dye if I can find the right colour
Did your red battery light come on using the two small gauge with 30amp fuse I’m in process of doing this, is this 12 gauge? All of a sudden, my consumer battery is getting hot. My car is charging the correct way not over 15v I get 13.95 consumer battery 14 starter battery I’m going to disconnect my amplifier and put it to the starter battery and state of the consumer battery.
No I had no red battery warning lights on the dash. I once had a hot rear convenience battery, but I think ti was due to driving for 6 hours straight twice a week for 2 years that may have damaged it. There was a bad smell that came off the battery too. I changed it with another genuine Mercedes battery, no issues since.
How did you decide on using 30A fuses? I wonder if a much smaller rating would work. I suggest trying out some really "small" fuses, such as 1A. Then if those blow, try 3A, 5A, etc until you find a value that doesn't blow in normal operation. I think that would get you the best protection. My thought is, 29 amps might be enough to start a fire still, but not blow the 30A fuse
It's a great question, there has been a lot of discussion on the forums and some people have gone smaller to say 20A. No harm in trying, if it blows then you can go higher.
The key objective is to avoid current flow through the BCM in the case of a malfunction, this could be water ingress etc. As I'm sure know I =V/R we know the volts sits around 14VDC however the current and resistance will vary especially as there is a front battery and rear. I have fitted 30A fuses and the simple test would be keep it simple and drop down to say 20A and see if they hold after a few weeks of driving and use.
not quite, the BCM over time can be affected by the current surge, especially if the rear battery has been jump started, as it should not be used, only the front.
Really useful video thanks. I intend to do this mod as some of the reports of fires are scary! I’ve read elsewhere that the order of disconnection/reconnection of the two batteries is critical to avoid electrical problems. Did you find that was the case?
Did you generate this thoughtful mod yourself? I haven’t seen it anywhere else. I would think the fuses could be even smaller as the box doesn’t require much current to operate. Parts ordered for my 2005. THANKS
I wish I was smart enough to have come up with this, 😳 I got the info from the forums I am a part of there are many people who have lost their SLs. You are correct about the fuses being smaller, some people are trying this out to see.
Any idea where the moisture is coming from? I lifted my sparewheel the other day, and noticed underneath the wheel face was damp. Don't think it was leak...
I did a video on prevention of water ingress into the boot. Its usually from the top seal, I found a method to use a tube to stop the leak. ua-cam.com/video/0PBCzLRVNew/v-deo.html
If your amp is just wired to the positive of the battery and ground, then I do not see any issues. The amp will draw amps to it rather than the other way around.
I explain at the end of the video that the smaller 10 gauge cable is part of the design mod, the heavy cables will continue to perform, with minimal current now being sent to the BCM. Remember that the current draw is dependent on the demand from the source, to which the BCM does not draw a lot.
I note from the dual battery wiring diagram that the connection from the system battery to the BCM is unfused so that if there is a short to ground (due to moisture) in the BCM then there is nothing to stop the max battery current flowing to the BCM - so I agree with the rational for your mod as in the event of a fault it will likely prevent further damage to the vehicle. Nice job.
Thanks man, we need to do what we can to protect these cars
Yes I caught that at the end, I was just concerned about the gauge of the wire. I’ll definitely carry out this work on mine.
Love the site for the Merc so keep up the good work.
let me know how you get on !
Will do
Hi, well I was all set to do the mod this weekend after flying home from work, my neighbour knocked this evening to say she thought she saw smoke at the back of my SL. Guess what......
Luckily I caught it before the car caught fire but the wiring, module and some carpet has melted. Obviously the car is now totaled, but I want to get the car off the road and in to my garage. How do I get the car out of park, and the steering lock off? Any clues?
Another brilliant video on protecting the Merc from a potential melt-down. Thank you for sharing!
Glad you enjoyed it!
the timing of this is incredible
Im so glad, feedback how you get on.
you are the man you got my car in good shape, i love this car you help me keep it that way
Thanks so much once again for the generous supper 🙏🏼 thanks!
Thanks!
Amazing, that is so kind, you've paid for the wiring kit for me, 😁 I hope this video saves some Mercedes ! Thanks so much again
Great job! You should try to get the car as original as possible - grille, removal of boot spoiler, etc. These are future classics!
Give the steering wheel a go, its an easy job and will make the driving experience so much better.
Thanks, you are the first person to ever say remove the spoiler, the grille though I have had a few people say no but majority like it. The steering wheel I am looking at replacing with the wood combo, but may just dye if I can find the right colour
@@GrooveOn Great, trust me (like with BCM), it will look much cleaner/better without that lip - same for the blackout grille.
love the car but it will never be worth shit to much to keep up and to many other cars that are better price will just keep going down
Hey are those red 10g wire dont become hot?
Great video. Thanks!
Good after noon I would like to know what the kit is called and where did you. Buy it
Hi there you can purchase the kit I used from my Amazon Store: www.amazon.co.uk/shop/grooveon/list/3QSEV0B0USU12?ref_=aip_sf_list_spv_ofs_mixed_d
Did your red battery light come on using the two small gauge with 30amp fuse I’m in process of doing this, is this 12 gauge? All of a sudden, my consumer battery is getting hot. My car is charging the correct way not over 15v I get 13.95 consumer battery 14 starter battery I’m going to disconnect my amplifier and put it to the starter battery and state of the consumer battery.
No I had no red battery warning lights on the dash. I once had a hot rear convenience battery, but I think ti was due to driving for 6 hours straight twice a week for 2 years that may have damaged it. There was a bad smell that came off the battery too. I changed it with another genuine Mercedes battery, no issues since.
How did you decide on using 30A fuses? I wonder if a much smaller rating would work. I suggest trying out some really "small" fuses, such as 1A. Then if those blow, try 3A, 5A, etc until you find a value that doesn't blow in normal operation. I think that would get you the best protection.
My thought is, 29 amps might be enough to start a fire still, but not blow the 30A fuse
It's a great question, there has been a lot of discussion on the forums and some people have gone smaller to say 20A. No harm in trying, if it blows then you can go higher.
you know nothing about cars or electricity.
@@GrooveOn this isn’t about Mercedes or legal action. My post was directed at a particular person.
@@steveww07 oh sorry my friend, I hadn't realised, I've deleted my reply, thanks
The key objective is to avoid current flow through the BCM in the case of a malfunction, this could be water ingress etc. As I'm sure know I =V/R we know the volts sits around 14VDC however the current and resistance will vary especially as there is a front battery and rear.
I have fitted 30A fuses and the simple test would be keep it simple and drop down to say 20A and see if they hold after a few weeks of driving and use.
Did you say 30A on both fuses?? Yhanks for great vid!
@@JoelBlauvelt yes mate 30A for both, thanks if you subscribed
Is moisture the only concern as a source for a short ?
not quite, the BCM over time can be affected by the current surge, especially if the rear battery has been jump started, as it should not be used, only the front.
Really useful video thanks. I intend to do this mod as some of the reports of fires are scary! I’ve read elsewhere that the order of disconnection/reconnection of the two batteries is critical to avoid electrical problems. Did you find that was the case?
I've not read about the order of battery's, no mate. But just in disconnecting the leads, neg first, then on re doing the positive first
Thanks for the vid, great mod and essential if we wish to keep these cars on the road. My BCM has blown, any ideas where I can obtain another?
if you are in the UK try Mike at Prestige Parts or eBay.
Goto ebay there is a rebuild service for about 350
Did you generate this thoughtful mod yourself? I haven’t seen it anywhere else. I would think the fuses could be even smaller as the box doesn’t require much current to operate. Parts ordered for my 2005. THANKS
I wish I was smart enough to have come up with this, 😳 I got the info from the forums I am a part of there are many people who have lost their SLs. You are correct about the fuses being smaller, some people are trying this out to see.
Any idea where the moisture is coming from? I lifted my sparewheel the other day, and noticed underneath the wheel face was damp. Don't think it was leak...
I did a video on prevention of water ingress into the boot. Its usually from the top seal, I found a method to use a tube to stop the leak. ua-cam.com/video/0PBCzLRVNew/v-deo.html
Do you think my amplifier is causing problem with the BCM overloading it? I noticed you have an amplifier also
If your amp is just wired to the positive of the battery and ground, then I do not see any issues. The amp will draw amps to it rather than the other way around.
Do you know anything about the switch by the headrest that makes the seat go forward and back T/K you cannot find anything on it ?
It it playing up?, can you remove the switch and check the wires?
@@GrooveOn will do
Great vid, thanks. Would you recommend this for the facelifted 08 - model?
Yes, absolutely
Is it not risky using a smaller gauge cable despite it being fused?
I explain at the end of the video that the smaller 10 gauge cable is part of the design mod, the heavy cables will continue to perform, with minimal current now being sent to the BCM. Remember that the current draw is dependent on the demand from the source, to which the BCM does not draw a lot.
Sweet!
I don’t understand why you’re struggling so hard with the booth separator 😂 it takes one minute to take it out.