bha280

Hello, I am new to MB's but not cars, so I'll be detailed as I can to help with diagnosing the issue.

Picked up a 2004 E55 AMG with some mods a couple weeks ago, and within minutes of driving on my 9 hour drive home got the convenience features disabled message. About half way home a red battery error with a service now message came on. Then, about an hour from home the radio went out, and about 15 minutes later I smelled an electrical burning smell and the AC stopped working. Made it home and started the Google searching and found that the voltage regulator may be the issue. Went to pull the voltage regulator out and the back cover of the alternator came off in pieces and the regulator had already been changed.

Changed the alternator but forgot to put the cables back on because I was in a rush trying to get done before it started raining. When I put the cable on the battery it sparked bad and the clamp started melting to the terminal because the power cable for the alternator was touching the block. Corrected that, checked all the fuses (all good), and tried to start the car. There was a metallic clank and it ran very rough for a few seconds and died. Tried again and nothing. Battery had 12.37 volts but went to 9 when cranking, so I got a new battery. When I started it, got the metallic clank and rough running for a few seconds before it died again. Tried starting again and it clicked like the starter wasn't getting enough juice that usually means the battery is dead. Still had the red battery warning as well. I stopped there because I was disappointed and now I am turning to the community for some help.

Is it possible I fried a power cable to the starter, or is there some module or relay between the battery and starter I may have fried? Thanks for any input.

bobgodd

If you have any friends close to you that have Xentry, get them to scan for codes, possible it could tell you in detail what's failing. Just wanted to get that out of the way.

The two things that jump out to me right away, considering you had a short is the BCM (battery control module) that resides in the trunk near the battery. If yours is original to the 2004 model, it might have taken the brunt of the short as it's meant to analyze power needs. Also there have been I think 2 updated part revisions since the 2004 cars. I had to replace mine once on my 2004, and it was superseded by a new part number. Second thing that jumps out to me is the crank position sensor, which is a pretty easy replacement. I know when that thing fails the car won't run, but I don't know if it causes the exact symptoms you're describing.

Before you start throwing money at it though, you should try to get it scanned.

machild

In EPC there are no less than five BCM - the original and four superceded versions. Not sure what dates they all occured but the latest one 211 540 86 45 is the one to use.

kevm14

Geez. I wonder what the issues were that required that many revisions. I hope it was because the first 4 caused phantom electrical draws, the ultimate irony considering what that module is supposed to do.

bha280

Thanks for the input. What's the best way to check the BCM? Also, I tried to hook up my generic OBD2 scanner and got no power to it, if that means anything

zhmorrow13

for me it was buying a used one off eBay for $70 and I installed it along with a new aux battery (under the cabin filter box). Took care of my red warning

bha280

Got a BCM from eBay installed yesterday and the red battery warning on the dash went away, but still no start. There is a metallic chunk sound when I turn the key, then nothing. Maybe I fried the solenoid in the starter or something too.

Mijanboy

Try connecting another starter source - help your battery even if it is new. Starter box or starter cables + second car started. Will the starter start working?

SICAMG

Jump the starter at the starter and see if it spins the engine over.

bha280

I connected my other car up like I was going to jump the E55 and tried to start. It clicked about 10 times then nothing. Still no errors on dash showing either.

machild

Have you tried what @SICAMG suggested about jumping the starter? That bypasses much on the wiring and starting system of the car to simply confirm your starter motor can turn the engine over. This will confirm two items. The starter is either functional or not. If it is functional then you know you have a problem with the starting process system. Then you troubleshoot that.

SICAMG

+ 1 on Machilds theory. Do it and then move from there.

Mijanboy

​​​​​​​So far, everything points to the burned-out winding of the starter coil, which is so damaged that the connection of the other car had no effect. A damaged / burned starter coil winding will not signal the car to you. Likewise, this fault may not be detected by the diagnostic connection. Starter replacement or repair required. The starter must be removed from the car out. Disconnect the battery first. check the cables for tightness and damage. Then disconnect the cables from the spool, loosen the 2 screws and remove the starter.

bha280

Are you talking like old school touching it with a screwdriver or some other method?

bha280

That's what I was thinking but didn't want to hear lol. I'll see if I can get some kind of test on the coil to verify that's the issue.

machild

Generally, yes. I prefer to use a jumper wire with aligator clips to keep from accidently shorting the high voltage to ground. If the starter does not run when jumped it could be either the windings, as discussed here, or the solenoid. If it does not run then I would remove the starter from the car and bench test it to confirm the issue with it.

If it does run then you know there is an issue with the start circuit. It could be as simple as an internally corroded battery cable (which could also keep the starter from running when you jump it and the reason for bench testing using a different 12V power source). A corroded internal cable can not be visually confirmed and it can/will read 12V at the starter but can not carry sufficient current.

kevm14

I'll jump in and say that, yes, this is how you isolate starting issues. This is very basic stuff. I still remember the first "bad" starter I replaced like 18 years ago. The engine still didn't crank. It was a battery cable connection to the battery issue (it just clicked). Lesson learned.

Mijanboy

Yes, the starter can be tested if it is connected directly to another source. The problem is in a small space and there is a risk of a short circuit. That's why I'd rather take the starter out of the car. The old Mercedes w123, w124, w126 had plenty of space. Newer ones usually have little space to securely connect another source and there is a risk of a short circuit. If you are testing a starter outside the car and you have never done so, you have to be careful !! Never hold the starter in your hand or connect the power supply - risk of injury. The starter has tremendous power. Always fasten the starter somewhere in the vice. If the starter works, you need to find out if it is strong enough. Each starter works outside the car unless burned. But he can be weak. That's why it simply clicks in the car - it doesn't have the power to turn the engine. You need the help of another person in the garage. The other person connects the starter to the source. You use wood / to avoid damaging the starter / you try to fix the rotor so that it does not turn. The other person then connects the starter to the source. If he doesn't turn, he's weak. If it is OK, it cannot be fixed with wood. Even if you were as strong as Arnold Schwarzeneger. Never try to fasten the rotor with iron - there is a risk of injury or destruction of the starter. Always wood. The best thick stick is 1 m long. Pencil, skewers, toothpick NO .

That's why I wanted him to connect a spare source. He did and nothing has changed.

Mercedes has a terminal 50 / battery cable - starter / copper. How does a copper cable corrode internally in a car that has been in production since 2006? If there is no problem in the starter, then I believe in damage or poor contact / oxidation /. We will solve this only after the starter test.




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Mijanboy

When I took out my first starter (over 30 years ago), I connected it to the power supply and the starter worked. I mounted it back and looked for a fault elsewhere. I didn't know that the starter was spinning with all its might . I searched for a mistake for 3 days and found nothing. I almost went crazy . When I didn't know which way to go, I went to see my dad. Did you try the starter? Yeah, the first day - it's spinning normally. And Dad: spinning? Every starter spins you stupid unless it's burned. Does he have strength?
What ... what ... what ... what strength?

machild

Battery cables can develop corrossion inside the insulation just like seen on battery terminals. Electric current travels on the outside (not through the core) of the stranded wires. If there is corrossion it creates a barrier to the flow of current. Voltage can be seen and verified on such a cable but insufficient current will flow. It takes minimal current flow to close the starter solenoid - so the click of the starter solenoid can be heard, but the large current flow required to rotate the engine with the starter motor can not get through the corrossion.

kevm14

No, the skin effect does not limit current at DC or low frequencies. You have to get way up there into the 10 kHz+ range before that matters...

Mijanboy

what???? So when you see a strong high-voltage cable falling outside on the road / after a strong wind /, grab it by the center / core and remove it from the road to the side ... and nothing will happen to you ... Before that, I recommend calling a hearse. Just to be sure, if you're wrong in your statement.
The battery cable is not a coaxial cable. It has one conductor of electricity around the circuit and the other, which is called the core, goes through the center of the cable, but even here I would not recommend touching the core, because usually it is the other way around.
If you need to buy jumper cables - how do you choose really good cables that will start the V8 cdi or V12 in the winter immediately after connection, even if the battery is completely dead and outside -30 ° C? What is a crucial parameter for jumper cables?

ModE211

Try to jump the starter while the key position is turning to start and see if it will start.