06 cls500 need mercedes benz/expert technician
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06 cls500 need mercedes benz/expert technician
i have a 06 cls500. so basically it been having a battery issue , where something in the car is draining the battery so every night if i use the car and i’m done with it i would take the battery off , been doing this for like 2-4 months , so now 2 weeks ago i went to the car and it was dead , i had someone directly give me a jump with cables and for about 10/15 and it finally started after fixing the terminals quite a bit just moving it around , then it finally turned on after a long battle. i drove it around for about 10 mins so the car would catch itself i seen the gas tank is low but the gas light didn’t come on so i parked it and rolled down all the windows and turned the car off and it was off for 5 minutes and i tried turning the car back on and they key didn’t turn at all in the ignition hold , it was stuck in one place and the wheel was locked also , i can’t move the gear box , lights would turn on in the car but the headlights are dim , and on the dash it sometimes says does not recognize key , tried changing the battery in the key still nothing changed. the car would not crank or turn over at all just lights inside sometimes and headlights are dim , and on the dash it sometimes says “reduce brake” . i went on youtube and google to see what might be the issue and all i’m seeing is the EIS the electronic ignition system and the starter relay.
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Joined: Jan 2007
Posts: 309
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From: Central Pennsylvania
1994 S420 RIP (2/8/13), 06 CLS55, 02 ML55, 94 TT Supra, 89 Maserati 228, 911 Porsche Carerra
Well you have several issues going on. First you need to check alternator output. If voltage is 13.8-14.2 alternator is fine. You got it started so that rules out starter issue. How old is your battery? May need it changed. If lucky they last 2 years and you change both not just one. Then the drain. I had two one in the audio gateway which I bypassed the other in the ignition subsystem which turned out to be a sticking relay because the drain was intermittent. Get a light bulb and hook it between the battery terminal and the post in series. Then pull one fuse at a time and see which one dims the bulb when pulled. You got work to do but the car is quite repairable. good luck
