Visit Workshop Brakes light
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From: Los Angeles, CA
'03 E55 (My Daily), '01 ML 320 (Wifey), Twin Turbo '69 Camaro (In Progess)
Visit Workshop Brakes light
I had the warning light come on a few days ago and was concerned about my car dying on me on the freeway and my brakes not being available due to SBC shutdown! Took the car in and they found out that the battery was dying. SA stated that the front battery was responsible for starting the engine--not the trunk battery. Not sure if that is correct as I can't imagine it would have enough cranking amps. Can anyone verify this?
Am getting some other things checked out and found that my supercharger clutch was going out. Thank God for warranties! My SA stated that the SBC system was covered through 2013 on my car, provided that brake fluid is replaced every 2 years.
Am getting some other things checked out and found that my supercharger clutch was going out. Thank God for warranties! My SA stated that the SBC system was covered through 2013 on my car, provided that brake fluid is replaced every 2 years.
Last edited by bbearden; Mar 26, 2009 at 01:11 AM.
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From: Denver, CO
Formula Mazda, Beast Junior...400HP 135i
I was under the impression that the rear battery runs everything and the front battery is used as an emergency backup for the SBC and other systems.
Also, there is NO WAY the front battery is big enough to crank the engine! My race car has a battery that is about the same size as the front one and on a cool day, it won't fire the engine over without a booster pack and it doesn't have a big a** 5.5L V8 to crank.
Also, there is NO WAY the front battery is big enough to crank the engine! My race car has a battery that is about the same size as the front one and on a cool day, it won't fire the engine over without a booster pack and it doesn't have a big a** 5.5L V8 to crank.
Thread Starter
Super Member
Joined: Aug 2003
Posts: 626
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From: Los Angeles, CA
'03 E55 (My Daily), '01 ML 320 (Wifey), Twin Turbo '69 Camaro (In Progess)
I was under the impression that the rear battery runs everything and the front battery is used as an emergency backup for the SBC and other systems.
Also, there is NO WAY the front battery is big enough to crank the engine! My race car has a battery that is about the same size as the front one and on a cool day, it won't fire the engine over without a booster pack and it doesn't have a big a** 5.5L V8 to crank.
Also, there is NO WAY the front battery is big enough to crank the engine! My race car has a battery that is about the same size as the front one and on a cool day, it won't fire the engine over without a booster pack and it doesn't have a big a** 5.5L V8 to crank.
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ML550
The front auxillary battery is for supplying power when the main battery voltage is low. Attached is a detailed explanation of the two battery set-up. Hope this helps.
Last edited by komp55; Feb 19, 2013 at 04:36 PM.
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From: Denver, CO
Formula Mazda, Beast Junior...400HP 135i
Thread Starter
Super Member
Joined: Aug 2003
Posts: 626
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From: Los Angeles, CA
'03 E55 (My Daily), '01 ML 320 (Wifey), Twin Turbo '69 Camaro (In Progess)
Awesome, thanks for the post! SA has stated that both batteries need to be replaced. That said: what else could have failed to cause them both to go out other than really $h*tty luck? I inquired about the battery control module and alternator and he stated they both checked out fine. My question is: what is the coincidence that both go out at the same time?! I did admittedly leave an accessory on that caused that batteries to drain about a week ago. Jumped it before leaving for work and they have ran fine ever since though they both are not holding a full charge. Since it was in the shop, they checked out the S/C clutch and are replacing it along with a brake fluid change for the SBC system. Didn't plan to spend $750 when I have a warranty! At least all preventative stuff is done for a long time...
