wannawagon

I have a 2006 ML320

I only just bought it, It had code 5967 on ABS ASC but I cleared the code using a Snap-On Solus scanner and bought the car (at auction).

I went to pick up car and now the code is back on and wont be cleared as previously

The code 5967 comes up as "low voltage supply to high pressure pump"

I am wondering if "High pressure pump" is generic for the whole ABS pump unit or just the pump within the whole unit?

I took the plug off the pump and cleaned the contacts (all looked good) and interestingly the code came off for about 100m (30 seconds) of driving.

I had experience with an E46 BMW (similar looking ABS pump unit) and the two long conectors running down to the ABS pump motor fracture at the PC board - the actual repair is easy - just cutting the housing away without damaging the PC board was difficult (I did wreck one in the process).

I don't think my problem is battery related as 12.2 on standby, and also I put a jump starter on it to help at start up.

Any help appreciated

I do have access to another 2006 ML320 (with no codes up)

Maj. Dundee

There are a few models with a 320 handle. Which one do you have?

wannawagon

164.122 going by the VIN

Sorry about slow reply - Internet issues

wannawagon

Just thought I would add that the car is NOT 4matic, just std AWD.

Maj. Dundee

With the eng. running, check both contacts for 12v on fuse #6 in the Eng. Prefuse Box and do the same for fuses 109 & 115 in the Eng. Compartment Fuse Box.

If the fuses are good then the problem is probably that the brushes in the pump motor (Green arrow) are worn out.

Post back with results of fuse checks.

wannawagon

Big thanks, I have done 109 and 115, but was not aware of 6. I will do this tomorrow and get back.

Maj. Dundee

M/B 4matic & AWD are one in the same.

wannawagon

just a dumb question - how do I open the front pre fuse box?

wannawagon

Ok - I got into the pre fuse box (pushed heaver at the side tabs and wiggled - it looks like someone else had been there before me as one of the tabs holding it to the chasis was broken).

All the contacts were good for all 4 fuses so I got more adventurous

I checked the part number on the top of the pump control module with the other ML320 I have here (both 06 CDI) and they were both A251 545 08 32. so I pulled them off and swapped them.

The one off the "good-old" car had no codes in the "bad-new" car, and the one off the "bad-new" had codes in the Good car.

So I assume it is the control module.

I checked the resistance between the two contacts going down to the abs motor and the good one read 22 meg ohm and the bad one read 91 kilo ohm so less resistance on the "bad"

I can't help thinking it is the same as the BMW E46 I had years ago that developed fractures on the PC board where the motor conectors solder to it. I remember I killed one E46 pc board when I was trying to open the box (cut the PC board)

Has anyone got any good ideas? or is there a check resistance hidden in some MB literature somewhere?

The other 320 I have here is my Wifes - I think she would notice the warning lights.

wannawagon

just wondering if anyone was a wiring diagram of the abs control module?, assume one of the prongs to the motor is always live when the plug is connected? assume the 5967 code picks up voltage on one of the prongs? it would be great if I knew which pin on plug was feed to motor so I could check for continuity

Am I right in thinking there is no ABS relay for the pump on the W164? Assume the "-" is made or broken by the control module? , It would be easy if there was a relay (like in most cars) but I have not found anything on the fuse charts (or am I reading them wrong?)

Maj. Dundee

Here are the wiring diagrams with legends.

wannawagon

Thanks again - really helpful and heaps of info.


Can you see if fuse 109 ( in F58 Engine compartment fuse block) permanently on?, only on with ignition, or only on from a relay?


If it is only on with a relay it's location would be great.


I am trying to see if the pump is powered by pin 32 with 16 being its return? (they are both 2.5mm)


Thanks again for your help ( I realize you replied before 5 am NY time)

Maj. Dundee

There are no relays in the system.

The white box w/# inside signifies the amperage of the fuse.

The #30 and #15 signify the circuit it is on. 30 means it is hot at all times. 15 means that it only becomes hot with the key on or engine running.

wannawagon

Thanks once again, nicely explained.


I was hoping I could have bridged the motor drive directly to 2 pins off the plug (the early E36 BMW powered their pump this way and had a separate control unit - simple and had the advantage the vibrations from the motor were going through a flexible wire - not a rigid connection on a pc board.


I will see if I can find a reasonably prices module and if I can I will firstly "break into" my module and see if I can repair repair it (hoping it is the solder conection down to the motor)


I will post back how I go - it may take a while

Maj. Dundee

Check the wiring harness to the hydraulic unit. Strip the harness as far as you can and look for corrosion or severed wire/s/

wannawagon

Thanks , will do - I will also check voltage on 1,4 and 32, and check resistance to earth on 16,47


I find it weird that there is no relay - unless it is built into the module -


I think my fault is in the module as it through up error in the other car (and the other cars module didn't throw up error in this car). But will check as above incase it is coincidental. I will also check if pin 32 is direct to motor? long shot I know - with thought that the earth is controlled through the module to engage motor ( error is low voltage supply) - sort of hoping I might have a bad solder on that line. I can also check resistance between same pins on known good module.


Thanks again

wannawagon

Ok - well done a bit of testing - and probably a bit of damage.


In the process of pulling the module off the pump one of the contacts to the motor touched the pump body (earth) and I had a spark and blew the 40am fuse (6). I replaced the fuse (evidently in Australia it is know as a "Midi Fuse" ).


Now I get the pump running when I have the ignition off and the module attached to pump and its is plugged in. NOT GOOD.


I checked the following off the module - the Right side (engine side) prong is probably earth, and on both the modules (the good one off wifes car, and this one) it reads 0.6 Ohm (nearly dead short). Now the Left side reads 0.6 Ohm on the BAD pump, and 110 KOhm (nearly open circuit) on the good pump.


All I can think is that there is an internal relay and I have fused it closed so pump runs all the time......


I think I need a new module.


I phoned the dealer and he says my part number


A251 545 08 32 was superceded twice. (at least) once to A251 545 11 32 and now is A251 545 40 32.


I am thinking that I will try and chase a A251 545 40 32 from a wrecker and check the date code, hope it will be newer and give me less issues. I will probably chase this from the USA as they want too much here (and car can wait til I get it)


Does it sound like the right thing to put in a later part number?, or keep to the original part number?.


If I do either will I need it to be reflashed or because I am putting in a 2nd hand it will already have been flashed ?


I don't have access to a STAR but I can borrow a Snap-on Solus


Cheers

wannawagon

Ok - well done a bit of testing - and probably a bit of damage.


In the process of pulling the module off the pump one of the contacts to the motor touched the pump body (earth) and I had a spark and blew the 40am fuse (6). I replaced the fuse (evidently in Australia it is know as a "Midi Fuse" ). I am still unsure why this conector was hot? as I thought it would only be hot when the pump motor was activated....


Now I get the pump running when I have the ignition off and the module attached to pump and its is plugged in. NOT GOOD.


I checked the following off the module - the Right side (engine side) prong is probably earth, and on both the modules (the good one off wifes car, and this one) it reads 0.6 Ohm to pin 47 (which is the 4mm earth pin) (nearly dead short). Now the Left side to Pin 1 (4mm positive off Fuse 6 reads 0.6 Ohm on the BAD pump, and 110 KOhm (nearly open circuit) on the good pump.


All I can think is that there is an internal relay and I have fused it closed so pump runs all the time......previously it might have been stuck open (this low voltage to motor error)


I think I need a new module.


I phoned the dealer and he says my part number


A251 545 08 32 was superceded twice. (at least) once to A251 545 11 32 and now is A251 545 40 32.


I am thinking that I will try and chase a A251 545 40 32 from a wrecker and check the date code, hope it will be newer and give me less issues. I will probably chase this from the USA as they want too much here (and car can wait til I get it)


Does it sound like the right thing to put in a later part number?, or keep to the original part number?.


If I do either will I need it to be reflashed or because I am putting in a 2nd hand one it will already have been flashed ?


I don't have access to a STAR but I can borrow a Snap-on Solus


Cheers

Maj. Dundee

With your insistence that the problem was with the control module you have now created a nightmare for yourself. You never even said that you fully checked the wiring harness.

Now you will have to find a used module in Australia and install it and hope for the best.

https://www.ebay.com.au/sch/i.html?_...54032&_sacat=0

wannawagon

Thanks, I bought that one - ebay had another 10% off last night so wasn't too bad.

I didnt mention that I did check the harness, as far as I could strip it (only a foot) and it was good, I actually touched the motor connector to earth while checking voltages

I had also swapped in a good module from other car (and put bad module in other car) and all lead to my module bad

I still don't think that motor connector should have been hot (given the ignition was off-not on start up etc) it is open circuit to positive feed into module on the "good" module

Thanks again for your help. will repost when I get other module in

wannawagon

Just a quick note - This error finally went away a few months back (and about 5000km) by changing the pump motor - Maj Dundee was 100% right - I haven't worked out how to get into the motor to fix it but by changing the motor the problem has gone.

BenzBallin

Wow ..ok ..so is this the same as for the R350 ???

Maj. Dundee

Please UPDATE YOUR PROFILE in USER CP to include the year of your RL and whether or not it is a diesel.

Then in a separate post provide your full vin#.

BenzBallin

OK ,Thanx, i did now... i have the 2008 R350 4Matic Gas engine..and got the Esp ABS light.,,i scanned it with my iCarsoft Mercedes Scanner and got the # 5967 code reading Power Supply high pressure Pump

wannawagon

I assume it is - what is the part number on your abs controller - by memory mine was 251 545 08 32 (251 suggests R series)

Maj Dundee is right in saying we have no idea with your car as same model name (R350) for diesel/petrol