SL/R230 ABS red warning - MBWorld.org Forums

Jun 21, 2017 | 09:18 AM

Darrens

Thread Starter

Newbie

Joined: Jun 2017

Posts: 5

Likes: 3

2007 SL 500

ABS red warning

Hi.
I've had the red warning come up, ABS & ESR disabled - reduced braking
I've been having problems with a dash cam draining my battery so left on charge over night.
I spent several hours reading old posts on the subject, but resigned myself to trusting the main dealer or purchase a OBD2 code reader.

I needed to drive so went to the car earlier today, and error no longer showing on dash board. Drove 2x 15 miles without issues.

Can anyone suggest why a low battery (the one in the trunk) could cause this driver alert? The car started at least a dozen times easily when I was fault finding before placing the trunk battery on charge.

Is this just a coincidence?

Should I be worried about something terminal?

The only other thing unusual is the very hot weather we have in the uk at the moment.

Thanks for any replies

Jun 21, 2017 | 01:18 PM

kbob999

Super Member

Joined: Jul 2014

Posts: 992

Likes: 245

From: Tucson, AZ

'20 X5 M50i; '17 Ram 3500; Golf Cart; Bikes; Scooters

The braking system is run by the electrical, so low voltage shows the braking error. If you have a low battery, it will trigger this error.

After driving a bit, the charge will come up and all is well.
Sounds like you need to keep it on the charger, replace the rear battery, or disable all of the drain items before parking it.

A simple 12v cigarette outlet voltage reading tool (eBay) will keep tabs on your voltage. They are great for seeing where you are on volts.

Jun 21, 2017 | 04:51 PM

tandan

Senior Member

Joined: May 2005

Posts: 397

Likes: 11

From: san diego

2001 viper rt-10, 2007 SL65

Quote:

Originally Posted by Darrens

You too! San Diego is cookin. Highly unusual heat, but compared to the rest of the Southwest, we've got it easy.

Jun 22, 2017 | 08:16 AM

Darrens

Thread Starter

Newbie

Joined: Jun 2017

Posts: 5

Likes: 3

2007 SL 500

Fortunately Aircon still working!

Mar 14, 2018 | 02:08 PM

Darrens

Thread Starter

Newbie

Joined: Jun 2017

Posts: 5

Likes: 3

2007 SL 500

Quote:

Originally Posted by Darrens

Thought I'd post an update.

MB main dealer carried out a replacement as good will given car had full service history, was just under 10 years old, and the fault creates a safety issue.
Very happy with my main dealer!

Mar 14, 2018 | 02:31 PM

Racin_fool

Super Member

Joined: Feb 2007

Posts: 809

Likes: 74

From: Dallas, TX

2008 E63 wagon (1 of 62)

Did they say what part they replaced? Was it the front passenger-side SAM or something else?

Mar 14, 2018 | 03:22 PM

Darrens

Thread Starter

Newbie

Joined: Jun 2017

Posts: 5

Likes: 3

2007 SL 500

Quote:

Originally Posted by Racin_fool

Did they say what part they replaced? Was it the front passenger-side SAM or something else?

HI,
According to the email at the time, they called it "Brake Control Unit Replacement".

I remember that i did have to pay for another module. I don't have the name, but it was reference the star diagnostics not able to automatically access all of the other cpu information. Apparently the could access individual control units, but the 'broken' control unit is needed by star to talk to all of the other control units.
About £300 cost with some discount, - but a hell of a lot cheaper than the quote they originally gave me to fix the ABS alarm.

The ABS alarm was still terribly intermittent, and would go away by itself for a while, but no problems at all since the control unit replacement, so it appears they where 100% right.