ABS and ETS lights on/ I found the problem/LONG
 

This was on my 98 ML320, other vehicles may be similar.

Since these lights would come on instantly, after starting the engine, I figured I had a hard failure somewhere in the ABS/ETS system. See my previous entry on this subject of a couple days ago.

After checking the 40 amp fuse that feeds this circuit, I pulled the relay, K25, that feeds the ABS high pressure pump. I can test a relay on my workbench and it tested fine. I also noted there are at least 3 identical relays so rotating them into the ABS socket was also an option.

I had a wiring diagram that I got from the Tempe library, which has a free Mitchell repair access. It shows a red wire going from the load side of the relay to the ABS high pressure pump motor and then to ground. Putting 12VDC directly to the load slot of the socket SHOULD have run the pump, but it didn't.

Testing further, I unplugged the two pin connector which feeds the ABS pump and put 12 VDC directly to the motor. By pulling the sheath back, I was able to see the wire colors. Since brown is always ground on Mercedes, I knew to put the plus 12 VDC to the other wire, to insure the rotation was correct.

The pump ran smoothly! I needed to verify that power was reaching the pump assy.

Unplugging the 15 pin connector from the ABS pump unit was a little tricky. The sheath over the plug pulls straight up and then the sheath becomes a ramping device that pushes the connector out of it's socket. My fingers could start the motion but it took a little pliers to get enough grip to release this connector. The bottom two pins were hot and ground and fed through the housing to the 2 pin connector. With my temporary 12 VDC still connected to the relay socket, I found that 12 VDC was indeed reaching the ABS pump assy, but NOT getting through to the 2 pin connector. The problem had to be in the ABS housing somewhere.

NOTE: At this point I found it conducive to remove the driver's side headlight unit for more working room. A 5 minute task to figure out how to release the plastic trim strip under the headlight where two nuts were hidden.

The front of the ABS pump unit appeared to have a wiring acces cover and I got really lucky here as the whole actuator control and wiring came off by removing 4 small 6 point screws. It just slid off the 12 pins that seal the fluid side of the magnet assemblies, No fluid is released and I had the printed circuit board in my hand.

Checking with my VOM connected to read resistance on pin 15 to the pin on the two pin connector that feeds the motor, I found high resistance with considerable fluctuation whenever the pins were flexed a little. BAD SOLDER JOINT! Where have we heard this before? The manufacturer is ATE, a well known vendor, but who knows how many ABS pumps hit the trash can because of a simple joint failure. At $1200 each, I am glad I took the time to find this problem.

The PC side of the board was covered with a 1/4" of clear jellied sealant, easily removed with an exacto type knife. I cleaned the old joints with brake cleaner, then I soldered both pins and in minutes the unit was reassembled and tested. Zero resistance is good! I used some clear silicone to close up over the newly resoldered joints.

Suffice to say that I rejoiced when the engine started and both lights were eztinguished. Knowing that I had ABS again was a big relief too.

I took a few pictures and will try to attach them. If this file is already too big I will send a separate file. Thanks to all who took the time to reply to my pevious note.

Jim in Phoenix

Great that you could fix it and thanks for the writeup, Jim. I poked around the ATE website and believe this is a picture of the MK20 used in your ML:

http://home.comcast.net/~anthoni6/MK20.jpg

I am sure you have had many responses to this thread. I too have a 98 ML320 that has had the ETS and ABS lights "stay on", and planned to look into your solution this weekend. Was wondering if you had input on how often this solution resolved the problem, or where there other solutions that worked as well? just curious. Aslo, I have not looked for the ABS pump on my car, Is it located near the drivers side headlamP?

Abs Esp Lights On
 

Hi Jfreezn,
I to have suspected an electrical connection problem on my 2000 ML 320.
My question to you or anyone else with ABS unit is:
should the electric motor that is connected to ABS unit be running when engine is started.

Can someone with same vehicle check to see if motor is running by starting
engine and carefully placing your hand on electric motor to detect motor running or not.====PLEASE ONLY TRY THIS IF YOUR CONFIDENT AND WILL NOT CAUSE INJURY TO YOUR SELF.

Thank You

Wow, Jim, you really nailed this one; right down to the cold solder joint and intermittent behavior! I just finished fixing mine. It had the exact symptoms you talked about. Now it works great, thanks for the great instructions.

Don

abs ets & brake lights
 

Seems I have the same issue with my 1998 ML320. I just replaced the $12 brake pedal switch tonight and that did not fix the problem. Will check out the bad solder joint possibility this weekend.
After you fixed the root cause did you have to do a reset procedure or did the start-up diagnostic automatic procedure detect no faults on its own?
Thanks for the heads up.
Ken

Sorry for the long delay. No, the lights went out immediately, without any help from me. As soon as I started the engine, the lights went out by themselves.

1/2 similar problem ...
 

Found your info interesting. Yesterday my ETS light came on and has stayed on. I DO NOT have a ABS light on. Wondering if this could be related to a
similar soldering issue, or since I have only the ETS matter would you think
this may be a totally different matter ??

Thanks

You got it right on, Jim. I think this is a common problem. I followed your directions and could not get two of the four 4mm bolts out of the assembly, no matter how hard I tried. I managed to get the cover off (but almost all of the clips broke off), and dig out the jelled sealant so I could check for continuity with the bottom plug of the two pronged plug. The continuity was okay, but I couldn't manage to test if flexing it made a difference, but the bottom pin in the unit (the one that connects to the brown wire) did seem loose to the touch, (this can easily be tested without removing everything first). Anyway, I started the car to see if the problem was still there, and the ABS and ETS lights didn't light up!

If anyone else tries to get the little 4mm bolts out, be careful, as you can't get good leverage, and it's very easy to strip the heads. Make sure you have maximum pressure against the bolt before trying to turn it!

At least it's working for now (at least til I hit a bump at some point), but now I know exactly where the fault is, and know what to tell the mechanic if necessary. (Perhaps putting a little silicone in the plug might stabilize it enough to maintain contact if it recurs?)

Module OK, Problem was chafed wire
 

I sent the ABS control module out to Module Master in Idaho. They did a quick turnaround on the rebuild and guaranteed the work. However, as this did not fix my root cause I did some further investigation after removing the ABS control module and hydraulic pump assembly. It turns out there was a chafed wire which was consistent with the fault code. Instead of a $1,600 part and $600 labor (dealer repair prices quoted), it cost me about $0.10 worth of solder and probably a buck for shrink tube w/ sealant to waterproof the repaired wire splice.
This was on a 1998 ML320 with about 190k miles.
Ken

ABS/ETS lights on dash
 

Ken,

I was very surprised today, when I logged on to the forum, that my ABS/ETS thread was active again after 20 months. I should mention that I have had absolutely no ABS problems since the cold solder joints were repaired.

you mentioned a chafed wire and I am sure many of us would like to know if it was on the 2 pin connector or the 15 pin connector run. We could take steps to tie the cable more securely if you would care to reveal where it needs attention.

Thanks,

Jim in Phoenix

Jim,
Good point and happy to oblige. The chafed wire was in the harness that runs behind the driver's side headlight and feeds the 15 pin connector that plugs into the back of the ABS control module/hydraulic pump assembly. It was the wire that feeds Pin #13 in the connector block but it could have been any of them. After doing the splice repair and weatherproofing, I also wrapped the harness in new friction tape to preclude further abrasion of the wire insulation. No problems since doing the fix in early January '08.
Ken

Thanks, I'll check mine out in the morning

Jim in Phoenix, 98 ML320, 155,000 miles

Can anyone tell me if this is left or right hand drive?

As I am a resident of the United States, the work described in all of my posts was done on left hand drive vehicles. I was not a member of this forum when I had the pleasure of living in countries with right hand drive vehicles.
Ken

I am in the same situation with these lights now. All three are on and even when restarting the car they don't go off. So where can I find the instuctions on this procedure.

Thanks

ML w/ ABS/ETS lights on
 

In which procedure do you have an interest? There are a few outlined in this forum thread from troubleshooting and repairing a loose terminal pin in the control module to rebuilding the control module, to removing the ABS hydraulic pump and repairing a wiring harness.
Thanks,
Ken

Well I thought to check out the bad solder joint in the ABS pump first, but it seems that the loose terminal pin might be little easier. Always try the easiest first, right?
It wouldn't be bad to have both so please advise.

Thanks in advance.

Procedure
 

Dear 00ML320,
Please check out the 8/31/2006 post by JFREEZN. Subject line is "ABS and ETS lights on/ I found the problem/LONG". Should help you go through the troubleshooting procedure.
Ken

I did read his post but he was relating to some pictures, so I thought that there might be a file on this. His procedure is clear for some people but I think I might need little more input on it .
Exaple: what is the PC side of the board?

Hi guys,

I also have this problem on my ML320 2001 but I don't know where to locate the ABS module. Can you please give me some guidance? Thanks.

Hi All,

regretfully, I'm combating a similar problem on my 00 ML 320. Lights BAS/ESP, ETS and ABS all on with ABS pump also running. This started yesterday even though I changed the brake light switch about a week ago. What's even more strange is the ABS pump came on and remains running even after the car is shut off and locked!!! I had to disconnect the battery to get it to turn off.

Last night I inspected the ABS wheel speed sensors at each wheel, checked wires to/from and also removed and cleaned the magnetic pickup sensors and hub surfaces (where the sensor reads from). These contacts get pretty dirty on the sensors. Put back together and restarted engine, performed lock-to-lock steering sensor reset and all lights off (and ABS pump) and stayed off during 15 minute test ride.

JFREEXN Jim, any chance you can post the photos you had referred to in the beginning of this post along with the great write-up? I will send you a PM with my e-mail just as backup. These would be very helpful if you could send them to me please as I do not believe I am out of the woods yet. Will test ride again today, is raining nicely and believe the water has something to do with the problem or possibly the circuit board is the source.

Thanks!
Mike

I sure would like to see some pics too. I tried the procedure described above but it seems that my ABS unit is somewhat different from the one they have. I have an integrated two pin connector that goes from the module to the pump, which can only be accesed when the module is off. The two pin connector seemed little burned out. So I am currently hunting for an used replacement unit. All three lights are still on.

cleaning the ABS wheel speed sensors fixed the problem for me. clean the sensors and the hub from where the sensor reads.

I'll give it a shot this week, thanks.

ABS problem question
 

Thank you all for the advice! I was about to order an ABS control module for 2002 ML 320. However after reading maybe I should check the wiring first.

Only issue we have that has not been duplicated is that at some points our ABS pump will start for no reason. The dash lights come on and the pump continues to run even after the car is shut off! The only way to stop is to remove the relay, after which we are good for a few days untill it does it again.

Has anyone seen this???

Thanks in advance
Ray

Can anyone describe the lock-to-lock steering sensor reset please? I plan to wirk on cleaning all the sensors this weekend.

Thanks
Ray

Hi Salleerd,

In order to reset the steering sensor all you need to do is turn the steering wheel at maximum in both directions.

jfreezen in Phoenix,

You just saved me some bucks!!! The fix is very easy to follow. Removing the windshield washer reservoir is a must if you have the 4 6-point screws frozen. Using a 4mm socket helps in taking it out.

Thanks!!!

otil2001

Same Problem in model 2001
 

Hi Jfreezn,
Thank you for your time you took to post such a comprehensive troubleshooting guide. I have a similar problem with my ML 320, model 2001. The three lights BAS ESP, ETS and ABS appear and today I felt some problem with the application of brakes too.
The different thing is that these three lights are not ALWAYS on, sometimes they disappear and most of the times these remain switched on. What does that mean? does that indicate that the problem is with switching of K25 relay or something big?
Waiting for your kind reply !
Thanks
Khurram

Now all the BAS Esp and ABS lights are permanently on - I have checked the K6, K25 relays and the brake light switches. These work perfectly fine. Will do the next procedure as directed by the forum
There is one thing bothering me. I got the new brake pads fitted some 2 months back. Can the problem be related to that? Could the mechanic have done something to disturb the circuit which caused these lights to switch on?
Thanks and advance!

Thank you thank you thank you!
 

Hi there, this is our first post to the forum we stumbled upon it through another thread on another forum trying to fix another problem with our 2001 ML320.
We (well the husband part of the we!) cleaned up the brake switch and then we hauled it's sorry self to get some computer diagnosis which told us that indeed, the brake light was faulty but had been fixed, code was cleared but left us with the information that the ABS pump had failed... erggh.We also still had all three lights up too of course.
We had quotes from AUD$1000 with ours traded in for a second hand one and AUD$1600 for a "reco" (plus freight- we live on a large island rather than mainland Australia).
BUT! WAIT! I found Jim's fantastic blow by blow post about his repair and the husband-half pottered off and resoldered the joint and siliconed it up as per Jim's post...perfect! No more nasty lights for us!
Thank you soooooo much Jim for providing such vaulable info- it is no only such a money saving but it was quicker for the husband-half to repair than it would have been to run around finding the parts!
YAY!
Thanks!
JJ and Jess

ABS/ETS Lights On
 

This is amazing! My post from 8/31/06 is still active. I just had a request from Greece for my photos,(That's what brought me back to this forum) which have apparently been lost in the shuffle. Also heard from a guy in Canada, and see a positive comment from Australia.

I will try to attach the pictures to this post. By the way, I haven't been to this site since 11/19/08, until today, is that about when they changed the name.

I still have my 98 Ml (168,000 miles) and the ABS/ETS lights have never returned since my repair, almost 4 years ago!

Finally, I see some private messages for me and I apologise for the lack of replies--I lost this site a couple years ago and they seem to have lost me as well, as I never got copies of any of these messages since then.

Lets see if I can attach the 4 pictures.

Jim in Phoenix

BAS/ESP Help!
 

Just joined! Interesting stuff. I'm dealing with a 99 ML 320. The BAS/ESP light only comes on when the car is moving...during start up and idle no light. Once you hit the road for a short distance here they come. Shut car down --restart -- no light. ESP/BAS only comes on whenth ecar in moving.

I was wondering, if anyone thinks the ABS cold solder fix described is what's in order here? Oh yeah already changed out the light switch.

Thanks for the input!

Mike

____________
99' ML 320
01' ML 320
63' Impala SS
99' Yukon 4wd

:cool:

I just bought a 2000 ML430 ... BONUS, it came with all three lights already on. The purchase price was adjusted due to the lights.

I pulled the control module and soldered the joint for pin 15. All the lights are still on! The pump DOES NOT run with the the relay jumped!?!?!?

The pump on the 2000 model year is slightly different than the '98 & '99. The motor on the hydro unit DOES NOT have the external two wire power feed. The feed goes the THROUGH valve block.

I cleaned all the wheel speed sensors but have not done the steering lock-to-lock reset. I do not know if the brake light switch has been replaced.

Questions:

1) Should the pump run when jumpered at the relay regardless of other problems?
2) Can the pump electric motor be removed from the hydraulic valve block without compromising the integrity of the non-ABS/EPS/BAS functions?

Thanks

Eddie

Seattle, WA

2000 ML430
1999 ML430

Update ...

The electric motor was removed from the pump and spun manually. The motor was connected directly to a 12V power source and it ran??? The motor was installed back onto the ABS Hydraulic Pump and the ABS control modual, the jumper was installed and THE PUMP RUNS! YAHOO!

The relay was installed, the car was started and the ABS and EST lights DO NOT ILLUMINATE! YAHOO!

But the BAS/ESP light is still on???? RATS!

What's up? Does this need to be reset at the Dealer?

Thanks

Eddie

Jim, that was world class trouble shooting! 45 min. and I was so happy. ETS and ABS lights out at start up, no steering limit reset. I pulled the relay, did a jumper from the two large lugs, no key on, no pump run, but I had 12 volts connected. I pulled the drivers headlamp, removing the lower trim for the 2 X screws, jumped the motor at the 2 pin, my hot was a red wire, pump runs, circuit pulled, solderd, mine was end pins 8 and 15. Really cool. Note, on another matter, the heat is on all the time on my ML 320. I have verified the A/C control module, located behind the center dash, is maintaining 12 V to the "Hot" motor direction all of the time. The temp set dial (not climate control, or set by degrees, manual type) is inputing a change in resistance, but referencing + or -. Interior temp sensor is at 4,500 ohms. Dealer wants 275 US. I will try frys for replacement component, when I figure it out. Keep it posted as I find out. Again, a most excellant, and satisfying solution you have, Thanks again, mark

I have a 2000 ML 320 and I recently had the BAS Control Module replaced b/c of this same problem, BAS, ABS, ETS lights coming on. It was a horrifically expensive repair, $3400. About a week after the repair, the lights came back on. I returned to Mercedes and they couldn't figure it out and, of course, the codes wouldn't come on for them. Several weeks later it started to happen more frequently. I took it to a friend who is a Lexus mechanic with a lot of German car experience as well. I left it with him and the pump ran continuously for at least 6 hours. He took the temp with an infrared thermometer and it was running at 302 degrees hours after I stopped driving. I took it back to Mercedes today. They are saying that the relay or release switch (not sure what they said) is sticking so they are replacing the release switch. My concern is this - if this fixes the issue, my friend said that the entire module should be replaced b/c it ran hot for so long. Thoughts? I have already spent a fortune on this issue and I can't say that I have a lot of faith in the dealership right now. By the way, the Lexus mechanic fully supports your advice about finding a mechanic (if you are not mechanically inclined yourself) who is wiling to take out the module and send it off for repair first. He said often it is resolved with a little soldering. Errrrrr. Things I wish I knew several weeks ago. Thanks for your fantastic thread. I only wish I had found it months ago.

Ok, so I started this project today hoping to save lots of money but ran into a problem. Get the light with no issues, unscrew the module with no issue but when I go to take wire harness off (it comes off during the ramping as described) the blue part of the wire harness stays inside the module and the back part of it disconnects from it. This exposes the pins and such from the plug and when I do attempt to separate the blue part of the harness from the module it starts to crumble and break, Yikes! I follow the harness back and it appears to be hard wired to the fuse box. Her is the question, can you just get that part of wire harness and reconstruct? Thanks

ABS & ETS lights- connector pin block
 

Charli411,
As I understand it, the 15 pin connector assembly block has begun to break apart on your ML. If this is the part you are talking about I can say that the same thing happened in my case too. After spending about an hour at the parts counter at the dealership near where I was working at the time, and working with a VERY helpful parts counter gentleman working the phones with MBUSA, he found the connector block part. I ordered one and it was perfect. The part number is 032 545 18 28. As I recall, it included the interior part where the 15 wire terminals plug in to the rear of the connector housing as well as the exterior "ramping shroud" which fits over it.

I will look for the tool I made to remove the wire terminals from the block one at a time and private message you with the photo.

That repair from January 2008 has been trouble free ever since.
Hope this helps you.
Ken

Hey there Kwmccauley
I need help with the ETS light also, for my ML320 98,
can you upload a Pic of the location for the metal cold solder joints that need solder?
I have tried it all and still no luck getting rid of this ETS Light,
thanks for your time and help
any advise about getting rid of the ETS problem is greatly appreciated!!

ETS lights
 

Lito420,
I would be happy to send you the photos of the solder joint areas but this project was 4 years ago for me and I have had some computer hard disk problems since then which caused a loss of many files including photos. So I do not have photos to send. That said, I should also mention that the solder joints turned out to not be the problem that I had with my '98 ML320. The problem I was having with the lights was caused by a wire that had chafed all the way through. It was a wire that ran to the ABS hydraulic pump. The wire that chafed through was located behind the left side headlight assembly.
Did you also try replacing the brake light switch near the top of the brake pedal arm?
Ken

Chafed wire repair
 

Lito420,
If you go back to post numbers 10 and 12 (5/20/08 and 5/21/08) in this thread there is some more information on the damaged wire that was causing the issue with my '98 ML320.
The vehicle is still running great at 244,000 miles with no further ETS/ABS problems since the January 2008 fix.
Ken

BAS/ESP-ETS-ABS Trifecta
 

Hi Everyone
Just wanted to share that the wonderful group at Hoehn Mercedes was able to save me heartache by replacing the relay PN#002-542-26-19, the relay contacts were worn out. They performed DTC's and found fault code C1401 for high pressure and return pump, the relay was inspected and the relay contacts were indeed worn out. Hydraulic unit relay replaced and codes were cleared. NOW if the problem comes back I ill need the BAS hydraulic unit parts retail $1,736.00 - relay $23.50 - I'm good. This forum really help me put my thinking cap on - It also doesn't hurt to have a dad and an uncle as East Coast consultants everytime I have an issue - Good Luck to all :P:D

Henriette
2001 ML320
98 C230
98 300E

ml 320 abs three lights are on
 

just giving my 10 cents here read these other posts and well i had all three abs related lights on ,on my dash....so i just went out and crawled underneath my 320 where the pump and motor are located behind the drivers headlight and just wiggled the 15 pin connector without even removing it just yet and sweet it worked.....and another thing to removing if you do so everything on mercedes are known to be torx bits internal and external which are metric which are not cheap as regular sockets and bits.....you can go to any auto parts store and by them mostly sold individualy.....also the cover over the 15 pin connector you wont break it off if you lay down underneath like i said before and just push the cover up it slides in place .....

BAS ETS ABS LIGHTS ON Replaced brushes ABS motor
 

After reading the other post. I jumped the relay as suggested.The ABS motor did not respond.I took a hammer and tapped on the motor it started and the lights went out.The motor obviously needed brushes .So I removed the motor from the ABS unit.Only two torx screws hold it on.Be careful and try to leave the end cap bearing in the unit.If it comes out with the motor there is a torx plug on ether side of the pistons that can be removed to enable installation of motor.I took the motor to several auto electric shops before I found one that was willing to replace the brushes as they have to be hand cut.After re installing motor all lights are off.This is a better option than buying a used ABS unit that is likely to have worn brushes and likely to fail. Mercedes had scanned my vehicle before repairs and told me it needed an ABS unit and a ETS sensor which is also very expensive.Save yourself some money and do some trouble shooting. ;)

Kudos for Jim in Phoenix!
 

I acquired my '98 ML320 about 6 years ago. The ABS lamp lit sometime later, and the local MB dealer had "never seen this before", so used it sans ABS for years. I stumbled upon Jim's post, and being an electronics tech, thought I would check it out. The weather was 80f when I resoldered the pc board (2 wire connector). Two days later, even though the ABS light was off, I ran over some icy road to see if it REALLY worked. It did!

Thanks Jim!

2002 ML320 +- 25000km
My BAS ESP - one light only on the instrument cluster remains or stays on while driving.
The only thing I did was change the headlight on the drivers side.
Is it possible I may have disturbed the wring harness running to the ABS motor?
Where about is the ABs motor in relation to what I did?Any advice woud be really great please?

ABS Wiring
 

If the 2000 ML has the same layout of the ABS system as the 1998 ML then then some of the wiring passes behind the driver's side headlight. The ABS pump motor is part of the assembly you can see under the hood with all of the metal brake lines coming from it.
Hope this helps.
Ken

Thank you Ken - kwmccauley For responding
Forgive me I really have to work on my communication skills - I should have said that I changed the headlight BULB but I did reef or disturb the black harness as the little backing plate to the bulb fell down there between the windshield water bottle and the back of the headlight housing and the one harness runs along the side of the headlight and the other underneath housing cover and trust me you will be touching the wire harness along the side to get that back cover back on as the space to work within is so limited and the cover has little pesky tabs.

So I guess the question is whether these wires or wire harnesses are relevant to the abs motor and I could have disturbed an already fragile soldering from way back there in relation to where the pins and the abs motor sits?

My answer is yes it is possible -- (thanks to Ken yes the abs motor is to the side. I always thought it was under the fuse box and the water bottle - but it is slightly to the left between the engine and the water bottle)
POSSIBLE yes as one cannot see the wiring connector or plug to the abs motor.
How would you advise removing the entire headlight housing or the windshield wiper water container or both??? to find the brocken wire area?


Perhaps I should take a picture