Electrical Chaos CL65
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Junior Member
Joined: May 2021
Posts: 18
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CL65, M2C, Ducati 748
Electrical Chaos CL65
My car has been sitting in the driveway for the past few months.
Yesterday I drove it about 3 miles to get gas and all heck broke loose.
I pulled up to the pump pressed the start / stop button to shut off the engine exited the car and suddenly it began calling 911 and could not make it stop.
I immediately drove home while apologizing to the 911 operators. I disconnected the antenna splitter so it can no longer connect to the cellular network and complete a call.
Now my car is possesed with so many strange electrical issues I honestly do not know where to start.
When I start the car most everything works except features that are blocked by SOS.
When I press / start stop without foot on the brake first and second press behave normally (although SOS is active); when I press the third time the electrical system should shutdown with the exception of exit delay in my case it does not but rather continues to try 911. I have to disconnect the negative front battery cable to shut everything off.
I am wondering if something electrical got wet while sitting outside? it rains a lot everyday in southwest Florida in the summer.
I checked the front and rear SAMs, trunk, under the front and rear seats, and everything is dry.
I will appreciate troubleshooting ideas.
Yesterday I drove it about 3 miles to get gas and all heck broke loose.
I pulled up to the pump pressed the start / stop button to shut off the engine exited the car and suddenly it began calling 911 and could not make it stop.
I immediately drove home while apologizing to the 911 operators. I disconnected the antenna splitter so it can no longer connect to the cellular network and complete a call.
Now my car is possesed with so many strange electrical issues I honestly do not know where to start.
When I start the car most everything works except features that are blocked by SOS.
When I press / start stop without foot on the brake first and second press behave normally (although SOS is active); when I press the third time the electrical system should shutdown with the exception of exit delay in my case it does not but rather continues to try 911. I have to disconnect the negative front battery cable to shut everything off.
I am wondering if something electrical got wet while sitting outside? it rains a lot everyday in southwest Florida in the summer.
I checked the front and rear SAMs, trunk, under the front and rear seats, and everything is dry.
I will appreciate troubleshooting ideas.
Out Of Control!!
Joined: Sep 2018
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From: unbegrenzt
2017 GLE350 4MATIC
Step 1: replace the battery, or batteries if it has an auxiliary battery
Step 2: inspect very closely all around the vehicle for water intrusion. Look under the front seat carpet, and on the floor all around the trunk perimeter. Many MB models over the years suffer water intrusion and with many electronics components located in the floor, bad things happen. W213 and W164 are two case studies.
Step 2: inspect very closely all around the vehicle for water intrusion. Look under the front seat carpet, and on the floor all around the trunk perimeter. Many MB models over the years suffer water intrusion and with many electronics components located in the floor, bad things happen. W213 and W164 are two case studies.
Thread Starter
Junior Member
Joined: May 2021
Posts: 18
Likes: 18
CL65, M2C, Ducati 748
Step 1: replace the battery, or batteries if it has an auxiliary battery
Step 2: inspect very closely all around the vehicle for water intrusion. Look under the front seat carpet, and on the floor all around the trunk perimeter. Many MB models over the years suffer water intrusion and with many electronics components located in the floor, bad things happen. W213 and W164 are two case studies.
Step 2: inspect very closely all around the vehicle for water intrusion. Look under the front seat carpet, and on the floor all around the trunk perimeter. Many MB models over the years suffer water intrusion and with many electronics components located in the floor, bad things happen. W213 and W164 are two case studies.
I did check under seats, removed rear seat cushions, checked trunk, removed trunk panel to expose rear SAM etc., took the cover off front SAM everything so far is dry but I suspect water somewhere else.
The batteries seem fine. the car started up with no complaints. Everything went south after a short drive.
In the meantime I have everything opened up and the A/C cranked in the garage to lower humidity.
Out Of Control!!
Joined: Sep 2018
Posts: 14,670
Likes: 4,574
From: unbegrenzt
2017 GLE350 4MATIC
I appreciate the help.
I did check under seats, removed rear seat cushions, checked trunk, removed trunk panel to expose rear SAM etc., took the cover off front SAM everything so far is dry but I suspect water somewhere else.
The batteries seem fine. the car started up with no complaints. Everything went south after a short drive.
In the meantime I have everything opened up and the A/C cranked in the garage to lower humidity.
I did check under seats, removed rear seat cushions, checked trunk, removed trunk panel to expose rear SAM etc., took the cover off front SAM everything so far is dry but I suspect water somewhere else.
The batteries seem fine. the car started up with no complaints. Everything went south after a short drive.
In the meantime I have everything opened up and the A/C cranked in the garage to lower humidity.
Thread Starter
Junior Member
Joined: May 2021
Posts: 18
Likes: 18
CL65, M2C, Ducati 748
With both batteries connected and the engine running I measure ~16vdc on the front and ~19vdc on the rear?
I have a lifetime of experience working on cars, motorcycles, boats, pretty much everything electrical and mechanical.
This CL65 is more than a little beyond my scope of experiance.
Thanks very much for the reply.
Member
Joined: Apr 2017
Posts: 134
Likes: 28
2014 ML350
Before I buy new batteries I am going to have to better understand what the heck is going on.
With both batteries connected and the engine running I measure ~16vdc on the front and ~19vdc on the rear?
I have a lifetime of experience working on cars, motorcycles, boats, pretty much everything electrical and mechanical.
This CL65 is more than a little beyond my scope of experiance.
Thanks very much for the reply.
With both batteries connected and the engine running I measure ~16vdc on the front and ~19vdc on the rear?
I have a lifetime of experience working on cars, motorcycles, boats, pretty much everything electrical and mechanical.
This CL65 is more than a little beyond my scope of experiance.
Thanks very much for the reply.
Thread Starter
Junior Member
Joined: May 2021
Posts: 18
Likes: 18
CL65, M2C, Ducati 748
I agree with Chassis, depending on what year your car is, the consumer battery in the trunk or the auxiliary battery could be failing. The same happened to me where the battery showed proper voltage when checked but the cells were starting to fail and caused all kinds of weird issues. Once replaced everything was ok. Definitely start with battery replacement if over 5 years old. Also, 16v and 19v for 12v batteries seems way off. Even with the engine running you should only be seeing between 13 to 14v. If you're reading voltage that high something may be wrong with your meter.
I figured the voltage was way off. As you said ~14vdc would be "normal" in my world with the alternator charging and something just north of 12vdc with the engine not running.
My trusty Fluke 112 DMM is not fibbing. I am going to replace the rear battery to begin with. The front battery has a date code of 7/20 so I'll leave it for now and check back later today.
Oh and I thought I read somewhere that there is some procedure for replacing the battery that involves tools I may not posses?
I'll have to figure that out too.
Thanks again for the help.
Last edited by BBM3; Aug 21, 2022 at 08:04 AM. Reason: added vehicle year
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Thread Starter
Junior Member
Joined: May 2021
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CL65, M2C, Ducati 748
@Renntech6509 @chassis
Thank you again for the help so far.
I just pulled the rear battery and you guys are correct it is done.
Thank you again for the help so far.
I just pulled the rear battery and you guys are correct it is done.
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Thread Starter
Junior Member
Joined: May 2021
Posts: 18
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CL65, M2C, Ducati 748
The new battery didn't help. I purchased a Mercedes specific scan tool (iCarsoft i980) that looks to be capable of looking at CAN level diagnostics.
If that doesn't help I am either going to try BenzNinja or have it towed to my trusted German car service specialist.
I have a feeling this is going to be a wallet buster.
Stay tuned I will keep this thread updated and promise once resolved I won't end with "Everything Fixed" without explanation.
If that doesn't help I am either going to try BenzNinja or have it towed to my trusted German car service specialist.
I have a feeling this is going to be a wallet buster.
Stay tuned I will keep this thread updated and promise once resolved I won't end with "Everything Fixed" without explanation.
Thread Starter
Junior Member
Joined: May 2021
Posts: 18
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CL65, M2C, Ducati 748
Senior Member
Joined: May 2021
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From: North of Houston, Texas
2013 CL 63, 2002 E 55, 04 Jaguar XJ8, 66 Jaguar XKE
I would definitely check codes. I have a CL63 and one time, driving on a long trip, it seemed like every light on the dash came on. Nothing worked, cruise control, lane change, nothing. I thought I was toast. Car ran fine, got it home (it was somewhat intermittent) and checked codes. It was a $50 wheel speed sensor. Replaced myself, took and hour and all is now well.
Hopefully you have a similar positive experience, other than the heart failure thing
Might try putting a good battery minder on the main battery. I have a CTEK that I use weekly. Again, Good Luck.
Hopefully you have a similar positive experience, other than the heart failure thing
Might try putting a good battery minder on the main battery. I have a CTEK that I use weekly. Again, Good Luck.
Thread Starter
Junior Member
Joined: May 2021
Posts: 18
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CL65, M2C, Ducati 748
I FIXT IT With Your Help
First off...Thanks for all of the help!
This is the solution to my CL65 Electrical Chaos Problem.
This might have cost a whole lot of $ if I had sent it on a flatbed to the dealer.
1) Replace the rear battery.
2) Erase all of the low voltage error codes stored in the many modules using a $100 iCarsoft i980
3) Reset the window switches, steering angle, throttle position sensor, and ECU.
4) Turn off traction control and make enormous smokey burnouts as Mercedes intended.
Thanks agin.
BB
This is the solution to my CL65 Electrical Chaos Problem.
This might have cost a whole lot of $ if I had sent it on a flatbed to the dealer.
1) Replace the rear battery.
2) Erase all of the low voltage error codes stored in the many modules using a $100 iCarsoft i980
3) Reset the window switches, steering angle, throttle position sensor, and ECU.
4) Turn off traction control and make enormous smokey burnouts as Mercedes intended.
Thanks agin.
BB
Thread Starter
Junior Member
Joined: May 2021
Posts: 18
Likes: 18
CL65, M2C, Ducati 748
I posted a couple here New Members Check In!
The car looks exactly the same today but with new rear tires.
Strange how quickly the first pair wore out.
The car looks exactly the same today but with new rear tires.
Strange how quickly the first pair wore out.
Out Of Control!!
Joined: Sep 2018
Posts: 14,670
Likes: 4,574
From: unbegrenzt
2017 GLE350 4MATIC
I posted a couple here New Members Check In!
The car looks exactly the same today but with new rear tires.
Strange how quickly the first pair wore out.
The car looks exactly the same today but with new rear tires.
Strange how quickly the first pair wore out.
