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hey im new to mbworld but hoping i can get help and not spend thousands of dollars at an import shop.
i drive a 2008 C-300 4MATIC Luxury model, its my first car and i got it roughly three months ago now. when we first looked at it we had to jump it, but other than that had only one issue up until recently, that being the ESP “not functioning”, as the dash tells me, and prevents me from slamming the gas all the way down, but i thought nothing of it cause i dont really care to do that.
lately however ive had some electrical issues. i hopped on the interstate and got a check brake pad wear signal and it all went downhill from there. on my way home i pressed the washer button on my turn signal lever for my wipers and my wipers kind of went haywire for a minute and then just turned off. then later i noticed my brights wouldnt activate and neither would my blinkers. i thought it sucked but its probably an easy fix so i shrugged it off, got out of the car and went inside but turns out my headlights never turned off and drained my battery. so we got my dads car and jumped it. my headlights remained on indefinitely, and my turn signal lever and headlight dial were non-functional, and i got a SRS Malfunction warning, which if im correct is for airbags? so anyway i drove it and parked it and tried to jump it earlier today, but all that happened was my alarm went off and my car still wouldnt start BUT i might have taken the jumper box off too early.
any ideas as to what this could be? ive checked every fuse related to my symptoms and they are all ok, none blown or corroded. all visible wiring is intact as well as far as i can tell. car also has no history of water damage and not really any noticeable signs.
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Pull up the carpet anyway and see if there are any signs that it had been wet. The drain channels for the sunroof get clogged with gunk and water backs up into the passenger compartment. Things can get wonky from there. Also check the Front SAM (fuse block) in the engine compartment for any signs of water.
Pull up the carpet anyway and see if there are any signs that it had been wet. The drain channels for the sunroof get clogged with gunk and water backs up into the passenger compartment. Things can get wonky from there. Also check the Front SAM (fuse block) in the engine compartment for any signs of water.
okay cool i will definitely check those out! ive heard a lot about the front SAM being a likely culprit but i dont own a Mercedes-dedicated scanner and even then the car wont start so i havent been able to look at it electronically. now as for looking at it, what should i be looking for? when i checked my fuses today they were all good and i didnt notice any type of wear in/around them except a load of pollen lol. but my fuse box cover is loose, do you think there might have been a moisture issue there? i didnt notice any corrosion but i dont exactly know where to look.
thanks for the tips tho ill check it out sometime soon when i dont have work and school and update!
oh, and is the SRS Malfunction warning something to worry about or just a probable side effect of electronic issues? its only ever popped up after jumping the car but i dont wanna ride around without airbags or some serious issue.
Car batteries don't last forever, and everything electrical starts with with your battery's health. Go to any auto store and ask to have your battery checked.
+1 on checking condition of the battery. Jump starting on a regular basis is not a good thing at all, especially on cars like this. Prolonged low voltage can cause a laundry list of issues.
The areas Jetta mentioned are large wire loom junctions for CAN BUS. There's one living underneath the carpets on front driver & passenger sides next to the doors & water intrusion (past or present) would be obvious. Staining on the foam underside insulation of the carpets, corrosion anywhere on the electrical connectors, even standing water present. It's not a large time investment to check sunroof drains by pouring some water in the sunroof channels & watching it drain (or not drain). The same goes for all drains at the windshield cowling (one central, & one on each side), & even the windshield seals themselves.
But again, charging system health/status is the starting point. I'm not 100% sure if you do have the "smart charging" program, (variable charging from alternator ranging from 12.6 - 14.9 depending on specific conditions), but if you do, the 'ol autozone charging system test will do you little favors. Their generic tester is for an alternator that constantly puts out high 13.x - 14.x voltage. Benz specific diag tools aren't massively expensive either. iCarsoft MB V2, Launch Creader, etc. The Ctek battery charger also is reasonably priced. I hope in today's insane nonsense that this is still the case, at least.
I've had plenty of electrical bs that was all due to low voltage, including madness at my turn signal stalk.
Most auto stores have battery load testers that they use to test batteries that fail under warranty (they don't want to give away free replacements unless certain the return is bad, not just discharged). Some other testers might not provide reliable results. Also have them check for a date code. If the battery is more than 5 years old, you're probably due for a new one anyway.
Most auto stores have battery load testers that they use to test batteries that fail under warranty (they don't want to give away free replacements unless certain the return is bad, not just discharged). Some other testers might not provide reliable results. Also have them check for a date code. If the battery is more than 5 years old, you're probably due for a new one anyway.
the battery sticker says 3/22 (its a DuraLast gold) but has had to have been jumpstarted multiple times, so my plan is to buy a new duralast platinum agm on my way home and try that. thanks for all of the help everyone and ill update later!
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Originally Posted by yvluc
the battery sticker says 3/22 (its a DuraLast gold) but has had to have been jumpstarted multiple times, so my plan is to buy a new duralast platinum agm on my way home and try that. thanks for all of the help everyone and ill update later!
It's either Walmart or Sam's Club that carries Duralast batteries. On another thread, we saw the Walmart prices were about $20 less than Sam's.
Walmart's in-house battery brand is EverStart, I believe. Autozone's battery brand is Duralast (this brand is also used on several of its hand tools. The last two batteries I've bought are Duralast Platinums, and they've performed reliably for me in my G550 and my Jeep Rubicon.
the battery sticker says 3/22 (its a DuraLast gold) but has had to have been jumpstarted multiple times, so my plan is to buy a new duralast platinum agm on my way home and try that. thanks for all of the help everyone and ill update later!
update: is not the battery. just spent $270 on a duralast platinum agm, good news is car started but bad news is:
alarm went off 2 or 3 times during process and would not shut off even when car started (idk if thats normal)
indicator lever still doesnt function
lights still dont turn off
planning to hopefully take it in to a shop tomorrow before i go to work
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Originally Posted by yvluc
update: is not the battery. just spent $270 on a duralast platinum agm, good news is car started but bad news is:
alarm went off 2 or 3 times during process and would not shut off even when car started (idk if thats normal)
indicator lever still doesnt function
lights still dont turn off
planning to hopefully take it in to a shop tomorrow before i go to work
Did you install the battery or the place you bought it? Mercedes are extremely temperamental when it comes to electronics and battery power. Does your car have one or two batteries? Did you connect the positve first when installing? Did you disconnect the negative first when removing?
Did you install the battery or the place you bought it? Mercedes are extremely temperamental when it comes to electronics and battery power. Does your car have one or two batteries? Did you connect the positve first when installing? Did you disconnect the negative first when removing?
Did you get a proper scan tool?
- I installed the battery myself with short tutorial off of youtube
- One main battery with an auxiliary in the trunk (99% sure of that not 100)
- Yes, positive then negative
- Yes, negative removed first
- I do have an OBD-II scanner but not a Mercedes specific, can’t exactly purchase one right now
I also did not run the scanner as the alarm was going off next to people in the pool and I was trying not to disturb. Is it possible the car thinks I’m trying to steal it? I don’t know why the alarm continues even when car is running.
Also, when alarm goes off blinkers are powered, so the problem has to be the indicator and not the blinkers
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Originally Posted by yvluc
-
- I do have an OBD-II scanner but not a Mercedes specific, can’t exactly purchase one right now
I understand. But a correct scanner is the most important tool you can have for a Mercedes. Generic OBD-II scanners are useless, if not misleading. Your car has around 50 individual control modules and your generic scanner is not going to cover all of those. Here is an example of a scan report from my LAUNCH scanner.
There have been a couple Launch scanners listed for sale at discount recently on the forum marketplace. Not sure they're still available, but worth checking. An OBD MB-specific scanner is more essential than a spare tire, IMO.
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
BlueDriver is not a bad alternative. It will download your brand of car to the app you use on your phone. But still about $100. For extra $30 or $40, LAUNCH is a better deal. BlueDriver is limited to scanning and clearing (most) codes.
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