BAS/ESP/ETS/ABS - Yet Another One of These Threads... - Mercedes-Benz Forum
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 41 (permalink) Old 05-27-2019, 05:14 PM Thread Starter
BenzWorld Elite
 
LWB250's Avatar
 
Date registered: Jan 2013
Vehicle: 65 220SEb, 97 SL500, 98 E320 Wagon, 2002 ML500 - former W108/W112/W114/W123/W124/W126/W140/W220
Location: Tampa, FL
Posts: 6,099
Mentioned: 14 Post(s)
Quoted: 1052 Post(s)
Garage
(Thread Starter)
Unhappy BAS/ESP/ETS/ABS - Yet Another One of These Threads...

Sorry to do this, but I've spent the better part of the weekend researching my issues and found little to nothing that corresponds with other threads for similar warnings. So bear with me and I'll do my best to present everything as best i can.

As a preface, I'm a 30 year Mercedes owner and a former high-line mechanic, so my diagnostic skills are probably at the higher end of the scale. I have a STAR/DAS system so I can access codes, faults and see active data as required.

So why could this be so darned perplexing????

Here's the deal:

2002 ML500
195k

Complaint:

BAS comes on randomly. Can often clear it with the "lock to lock" steering wheel turning. Will often come on maybe 10-15 miles later.

BAS/ESP/ETS/ABS will come on as a group, accompanied by the "Brake" warning light. This is accompanied by the peeping alarm that continues to sound as long as the car is moving. Come to a stop, lights remain on, peeping stops.

Running a full scan using the DAS system, the only faults that come up are C1140 (steering angle sensor) and C1306 (right rear axle solenoid valve).

ABS pump has been checked and it runs by doing an activation though DAS.

Voltage tests as prescribed in Star Tekinfo for the steering angle sensor are correct. Looking at actual values for the steering angle sensor in DAS reflect correct values. Steering has been zeroed and cleared both using DAS and with the "lock to lock" method as well.

Car was aligned recently (again, steering is centered properly and the steering angle sensor reflects this) and I have the same tires with lots of tread all the way around.

I replaced the brake light switch and installed it per the bulletin, as I had one on the shelf.

I suspect I'm looking at multiple issues here possibly, and this is why I say this:

I replaced a right rear caliper last week. I bled the system with my pressure bleeder, but the first time I put my foot on the brake pedal it went to the floor. Once it returned I had pedal, but the travel seemed long and if I maintain pressure on the pedal it will leak down very slowly. It's also spongy.

I'm wondering if when the pedal went to the floor the cups in the master cylinder might have been damaged. Based on this I'm pretty sure I need to replace the master cylinder.

Differential pressures at the master cylinder were checked in DAS and they're right on the money, so I don't see where that would cause an issue, but the leaking down can't be anything but the master cylinder. However, if that was leading to some of these alarms why doesn't it occur when the brakes are applied rather than just coming up as what appears to be random intervals?

The only other thing I can think of to toss into the mix is that the ECU box blower is not working. Totally dead, I've got a replacement coming later this week. I'm also wondering if it would be wise to disconnect the battery, disconnect all the modules in the ECU box and clean the connectors with contact cleaner.

And a proverbial red herring:

No horn. Fuses are good, horns are good. I've wondered if someone has been into the steering column and messed with the clock spring and/or things in that neighborhood. I'm not getting any error codes for airbags or anything like that, however.

I'm open to any and all suggestions at this point. I'm practically stumped.

Thanks,

Dan

Last edited by LWB250; 05-27-2019 at 05:53 PM.
LWB250 is offline  
Sponsored Links
Advertisement
 
post #2 of 41 (permalink) Old 05-27-2019, 06:22 PM
BenzWorld Extremist
 
Date registered: Jan 2004
Vehicle: 2004 ML500,Sport; 2014 ML550; 2009 ACURA TSX
Location: New York City
Posts: 857
Mentioned: 0 Post(s)
Quoted: 57 Post(s)
Check transmission code. Itís likely that one of the speed sensor on the wheel is bad. I had the same issue last month, case was bad left wheel sensor. P2403 code was stored.

photo attached.
Attached Thumbnails
Click image for larger version

Name:	IMG_5265.jpg
Views:	9
Size:	33.7 KB
ID:	2516176   Click image for larger version

Name:	IMG_1292.jpg
Views:	10
Size:	80.3 KB
ID:	2516178  
LWB250 likes this.

Last edited by johnma; 05-27-2019 at 07:21 PM.
johnma is offline  
post #3 of 41 (permalink) Old 05-27-2019, 06:24 PM Thread Starter
BenzWorld Elite
 
LWB250's Avatar
 
Date registered: Jan 2013
Vehicle: 65 220SEb, 97 SL500, 98 E320 Wagon, 2002 ML500 - former W108/W112/W114/W123/W124/W126/W140/W220
Location: Tampa, FL
Posts: 6,099
Mentioned: 14 Post(s)
Quoted: 1052 Post(s)
Garage
(Thread Starter)
Quote:
Originally Posted by johnma View Post
Check transmission code. Itís likely that one of the speed sensor on the wheel is bad. I had the same issue last month, case was bad left wheel sensor. P2403 code was stored.
Thanks, I'll look into that. I don't recall having any transmission error codes, but I'll run a check tomorrow and see.

Dan
LWB250 is offline  
Sponsored Links
Advertisement
 
post #4 of 41 (permalink) Old 05-28-2019, 12:53 AM
Lifetime Premium Member
 
mattml430's Avatar
 
Date registered: Sep 2008
Vehicle: 2000 ML55 sold😢 2013 ML500,😁 2015 C250 estate wagon, 1927 Dodge 4 sedan, 1929 Dodge
Location: Melbourne Australia
Posts: 4,357
Mentioned: 4 Post(s)
Quoted: 790 Post(s)
Lifetime Premium Member
Swap relay 25 with one similar and check the brushes in the ABS motor.
You still have a couple of other issues but thatís a start.


Sent from my iPhone using Tapatalk
mattml430 is offline  
post #5 of 41 (permalink) Old 05-28-2019, 02:24 AM Thread Starter
BenzWorld Elite
 
LWB250's Avatar
 
Date registered: Jan 2013
Vehicle: 65 220SEb, 97 SL500, 98 E320 Wagon, 2002 ML500 - former W108/W112/W114/W123/W124/W126/W140/W220
Location: Tampa, FL
Posts: 6,099
Mentioned: 14 Post(s)
Quoted: 1052 Post(s)
Garage
(Thread Starter)
Quote:
Originally Posted by mattml430 View Post
Swap relay 25 with one similar and check the brushes in the ABS motor.
You still have a couple of other issues but thatís a start.


Sent from my iPhone using Tapatalk
I've got some new relays on the way, as a couple of them appear to be slightly discolored as if they've overheated. I'll swap relay 25 this afternoon after work.

I've run the diagnostics on the ABS pump and it runs fine and without any noise to speak of, so I'm going to assume the brushes are fine. I can pull it if necessary (I've got the windshield washer reservoir out at present) but since it checks out in DAS OK I'm reluctant to be pulling it apart.

I found a bulletin last night that talks about corrosion on the ESP module connector which causes random errors, so I'm planning on disconnecting the battery and cleaning connectors in the ECU box later today.

Thanks for the suggestions, and keep them coming!

Dan
LWB250 is offline  
post #6 of 41 (permalink) Old 05-28-2019, 02:31 AM
Lifetime Premium Member
 
mattml430's Avatar
 
Date registered: Sep 2008
Vehicle: 2000 ML55 sold😢 2013 ML500,😁 2015 C250 estate wagon, 1927 Dodge 4 sedan, 1929 Dodge
Location: Melbourne Australia
Posts: 4,357
Mentioned: 4 Post(s)
Quoted: 790 Post(s)
Lifetime Premium Member
Also have a look at the ABS control unit connection, it is prone to corrosion from leaking water washer reservoir.
Pull the left hand inner fender and trace the ABS loom along and make sure it hasnít rubbed through to bare wires along the length of it.


Sent from my iPhone using Tapatalk
LWB250 likes this.
mattml430 is offline  
post #7 of 41 (permalink) Old 05-28-2019, 03:46 AM Thread Starter
BenzWorld Elite
 
LWB250's Avatar
 
Date registered: Jan 2013
Vehicle: 65 220SEb, 97 SL500, 98 E320 Wagon, 2002 ML500 - former W108/W112/W114/W123/W124/W126/W140/W220
Location: Tampa, FL
Posts: 6,099
Mentioned: 14 Post(s)
Quoted: 1052 Post(s)
Garage
(Thread Starter)
Thanks again for the suggestions!

As I’ve read through darned near every thread on these issues, I’ve seen this referenced as well. I inspected the ABS harness this past weekend and found no damage, the windshield washer reservoir does not appear to have been leaking, and I disconnected the connector at the ABS module and hosed it down with contact cleaner.

Dan
mattml430 likes this.
LWB250 is offline  
post #8 of 41 (permalink) Old 05-28-2019, 05:39 AM
BenzWorld Elite
 
Witek_M's Avatar
 
Date registered: Sep 2008
Vehicle: 1972
Location: Dallas, Texas
Posts: 6,351
Mentioned: 15 Post(s)
Quoted: 882 Post(s)
Quote:
Originally Posted by LWB250 View Post

BAS/ESP/ETS/ABS will come on as a group, accompanied by the "Brake" warning light. This is accompanied by the peeping alarm that continues to sound as long as the car is moving. Come to a stop, lights remain on, peeping stops.
For this issue drive around while watching live data for parking brake switch and brake fluid level switch.

Similar issue.
https://www.benzworld.org/forums/w16...ht=brake+fluid

https://www.benzworld.org/forums/w16...ht=brake+fluid

1972 280SEL 4.5
1999 ML320
2000 E320
2003 ML350
Witek_M is offline  
post #9 of 41 (permalink) Old 05-28-2019, 05:56 AM Thread Starter
BenzWorld Elite
 
LWB250's Avatar
 
Date registered: Jan 2013
Vehicle: 65 220SEb, 97 SL500, 98 E320 Wagon, 2002 ML500 - former W108/W112/W114/W123/W124/W126/W140/W220
Location: Tampa, FL
Posts: 6,099
Mentioned: 14 Post(s)
Quoted: 1052 Post(s)
Garage
(Thread Starter)
Thanks a bunch!

Trying to sift through this and separate all the various fault is a real challenge at times. I’m wondering if I’ll see any fault codes related to this when I scan it tonight? I’ll report back what I find.

Again, thanks!
LWB250 is offline  
post #10 of 41 (permalink) Old 05-28-2019, 10:38 AM
BenzWorld Member
 
reetp's Avatar
 
Date registered: Apr 2017
Vehicle: 2002 W163 ML400 CDi
Location: Spain
Posts: 133
Mentioned: 0 Post(s)
Quoted: 40 Post(s)
Garage
While you replace the ECU fan go through every connector you can find in the box. Literally pull out every cable you can.
The box leaks....
There are a few connectors buried right at the very bottom, and I found a few cruddy ones so cleaned the lot up while it was apart (I was actually looking for the brake pad sensor connectors).
Probably not your issue but worth eliminating while you are there.
reetp is offline  
Sponsored Links
Advertisement
 
Reply

  Mercedes-Benz Forum > Mercedes-Benz Vans/Trucks/SUV/Others > W163 M-Class

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Mercedes-Benz Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 

Title goes here

close
video goes here
description goes here. Read Full Story
For the best viewing experience please update your browser to Google Chrome