E55 voltage low again
Thread Starter
Senior Member
Joined: Oct 2016
Posts: 387
Likes: 18
From: New York
2005 CL55 (sold) C63 Coupe 2012 p31(sold) Audi 330awhp E55 511WHP(sold)Z06C6 550whp C63 LTH
E55 voltage low again
I got a longtube headers on my car and a pulley. IM saying that because the shop worker told me when he installed a new alternator for me that the headers were to close to the alternator and that ill prob run into a problem down the road. So i changed all the batteries, the small one in the engine bay and the rear main one in the back. I'm monitoring the voltage via dash and it seems like I'm having the same problem i had in the past where the car doesnt want to charge. The alternator is a OEM Bosch. Im afraid to give the car to a shop because everyone keeps screwing me over. The car has aftermarket front and rear e63 lights and it has a lowering module. the new alternator lasted me a 2 months but towards the end it would start to give out on me and i couldn't leave the car without being driven for a day. if it wasn't driven for a day it would die but now it seems like it won't charge at all on its own.
MBWorld Fanatic!
Joined: Jan 2014
Posts: 3,969
Likes: 1,317
From: Republic of Texas
'99 and '05 E55 AMG
Query:
-What is the voltage displayed at idle?
-What is the voltage displayed at 2500 rpm?
-What battery was installed as a replacement for the main battery?
-What battery was installed as the replacement for the auxiliary battery?
-Are all connections clean of corrosion?
-Are the points where the cables enter the battery clamps clean and free of corrosion?
Recommendation: purchase a Solar BA-5 Battery Tester and check both main and auxiliary batteries. Main battery should no no less than 500 CCA (and that is for an old battery) and, if new, should show ~900-1100 CCA. Auxiliary battery should show minimum 170 CCA when new and I recommend replacement when at 100 CCA or less. Yes, technically it is still "good" but the distributed digital control system in our cars does not like an unstable voltage on the main or auxiliary bus....
Header close to alternator only requires a heat shield. Either header wrap or a thin metal shield between header and alternator. This is not rocket science.
-What is the voltage displayed at idle?
-What is the voltage displayed at 2500 rpm?
-What battery was installed as a replacement for the main battery?
-What battery was installed as the replacement for the auxiliary battery?
-Are all connections clean of corrosion?
-Are the points where the cables enter the battery clamps clean and free of corrosion?
Recommendation: purchase a Solar BA-5 Battery Tester and check both main and auxiliary batteries. Main battery should no no less than 500 CCA (and that is for an old battery) and, if new, should show ~900-1100 CCA. Auxiliary battery should show minimum 170 CCA when new and I recommend replacement when at 100 CCA or less. Yes, technically it is still "good" but the distributed digital control system in our cars does not like an unstable voltage on the main or auxiliary bus....
Header close to alternator only requires a heat shield. Either header wrap or a thin metal shield between header and alternator. This is not rocket science.
Thread Starter
Senior Member
Joined: Oct 2016
Posts: 387
Likes: 18
From: New York
2005 CL55 (sold) C63 Coupe 2012 p31(sold) Audi 330awhp E55 511WHP(sold)Z06C6 550whp C63 LTH
Thanks for the replies everyone. I will be using your advice. I just saw all these messages today. I charged the main battery to 12.3 volts and I drove the car and it slowly dropped down to 11.0 and didn't charge up. I lifted open the hood and the engine bay smelled like burnt rubber near the alternator 
so idk what that means
so idk what that means
MBWorld Fanatic!
Joined: Jan 2014
Posts: 3,969
Likes: 1,317
From: Republic of Texas
'99 and '05 E55 AMG
Thanks for the replies everyone. I will be using your advice. I just saw all these messages today. I charged the main battery to 12.3 volts and I drove the car and it slowly dropped down to 11.0 and didn't charge up. I lifted open the hood and the engine bay smelled like burnt rubber near the alternator so idk what that means
so idk what that meansTrending Topics
Thread Starter
Senior Member
Joined: Oct 2016
Posts: 387
Likes: 18
From: New York
2005 CL55 (sold) C63 Coupe 2012 p31(sold) Audi 330awhp E55 511WHP(sold)Z06C6 550whp C63 LTH
MB World Stories
The Best of Mercedes & AMG
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
MBWorld Fanatic!
Joined: Jan 2014
Posts: 3,969
Likes: 1,317
From: Republic of Texas
'99 and '05 E55 AMG
True, that. I would hazard that the alternator is burned due to the report of the smell. Nonetheless, I concur on connecting to DAS to verify codes.
Alenpepic, you are aware that you can monitor your bus voltage using the instrument cluster? Should show around 12.2-12.6 with engine off and a good battery; with engine running should be around 14 volts. Youtube videos will show you how to bring up the bus voltage on the cluster.
Alenpepic, you are aware that you can monitor your bus voltage using the instrument cluster? Should show around 12.2-12.6 with engine off and a good battery; with engine running should be around 14 volts. Youtube videos will show you how to bring up the bus voltage on the cluster.
