[WE47B1ME]

Hi guys --

About a week ago the trio of traction lights (ABS / BAS / ESP) were coming on intermittently. Usually the system would reset it self, but they were coming on more and more sporadically, sometimes at start, sometimes 20 minutes into the drive, sometimes none at all in a 10 minute drive.

Carsoft threw me C1401 and figured the brushes in my ABS pump had finally worn down after 317k miles.

Here's where it's strange and different than all of the other threads I've been reading this morning. If the fault lights ARE NOT ON, I can jump relay K25 to get the pump going manually. If the lights are on, nothing happens when I jump the relay.

I bought a whole used ABS unit with the pump for $100 on eBay (yes, didn't feel like pulling the bearing to replace the brushes, and swapped it out this morning. Jumping K25 when I put it back together -- new motor spinning up just fine.

Crank the truck and let it run in the garage for almost 25 minutes, the lights all stay off. Fixed, right?

Back out of the garage, and the second I hit the street, all 3 are back on. C1401 is back. Go back inside the garage, can't get it running manually.

I'm also throwing the following:

P1520
P1113
P1111
C1025
B1041
B1042

I thought about replacing the whole ABS unit, but it's not throwing C1000? This feels like a bit of an electrical gremlin? Brake light switch was swapped out for a spare new one just to see, but that didn't do anything.

Was thinking it might be the Yaw or one of the speed sensors, but she's not throwing any codes to indicate that.

Any idea where to look next? Thanks guys.

 

[mattml430]

Try changing K25 relay for a similar one.


Sent from my iPhone using Tapatalk

 

[WE47B1ME]

Try changing K25 relay for a similar one.


Sent from my iPhone using Tapatalk

Hey Matt -- I see you went thru a similar experience. I swapped it, but the codes are still on. Don't know why it seems to only want to reset after the engine is cold? Usually overnight.

I'm thrown off as well by not being able to manually engage it with a jump wire once the lights are on and the relay is out.

 

[art_arev]

Have you thought that maybe the "new" motor could be faulty?
Why don't you just change the brushes in your original motor?

 

[43sqd]

I'm assuming that you did, but none of your postings say that you cleared the codes.

 

[WE47B1ME]

I'm assuming that you did, but none of your postings say that you cleared the codes.

Yes, I did. Sorry for not specifying. I cleared the Traction and BAS modules. The lights turn off, and come back on 2 seconds later.

And, it would seem a Happy Birthday is in order. Hope you have a good one!

 

[WE47B1ME]

Have you thought that maybe the "new" motor could be faulty?
Why don't you just change the brushes in your original motor?

I thought that, but then I thought it's too strange that it exhibits the exact same timing re: the system shutting down -- and the fact it was idling for 20 minutes without throwing the codes.

I'm still trying to understand why it won't manually engage when I jump the relay if the codes have shown up. Is it because the ESP module that sits under the fuse box has shut down power to the relay?

I'm going to open up my old motor in a bit to see how those brushes are.

 

[WE47B1ME]

Update with a video and pictures, because everyone loves visual aids.

Wanted to see how long the "new" motor would run with the truck cold. Not long. Also you'll see in the video, I could start and stop the motor once by jumping, but on second attempt, it would not spin up again.

Seems as if she's winding down, starving for power. I need to check power on the fuse panel now I think.

Also, the picture is my OLD abs pump motor. The brushes are almost toast, but there's still some life in them. Considering I live in LA, and the ABS turns on maybe once a year, this doesn't seem to be the reason why the system is failing. I'm leaning into electrical gremlin...

 

[Witek_M]

Power to relay f1k25 terminal 3 comes straight from circuit 30 unfused. Ground for the pump W9 is behind left headlight.

If you are heavy footed pump runs without your knowledge or consent as part of ESP. Yellow warning triangle comes on only if ESP reduces engine power through engine control module.

http://eurtonelectric.com/catalog/motors/mercedes_a1634310312_abs_pump_motor_repair

https://www.google.com/maps/place/E...637fe42!8m2!3d33.9471682!4d-118.0488753?hl=en

 

[WE47B1ME]

Power to relay f1k25 terminal 3 comes straight from circuit 30 unfused. Ground for the pump W9 is behind left headlight.

If you are heavy footed pump runs without your knowledge or consent as part of ESP. Yellow warning triangle comes on only if ESP reduces engine power through engine control module.

Mercedes A1634310312, ABS Pump Motor Repair | Motor Repair & Rewinds | Eurton Electric

https://www.google.com/maps/place/E...637fe42!8m2!3d33.9471682!4d-118.0488753?hl=en

Thanks for the rebuild links...I may go down that route after I've verified I have 2 bad motors, which I'm not ready to believe yet.

I think electrical gremlin.

And sorry, when it comes to that, it's not my strongsuit. What do you mean k25 power is coming from circuit 30. And is that where I need to check for 12v power?

I see the ground behind headlight, below where washer reservoir is. Connection looks fine?

 

[art_arev]

Change the brushes.....There is enough life to run the motor once, when you jump the relay.........Brushes are you #1 suspect.

 

[Witek_M]

Thanks for the rebuild links...I may go down that route after I've verified I have 2 bad motors, which I'm not ready to believe yet.

I think electrical gremlin.

And sorry, when it comes to that, it's not my strongsuit. What do you mean k25 power is coming from circuit 30. And is that where I need to check for 12v power?

I see the ground behind headlight, below where washer reservoir is. Connection looks fine?

This is not religious subject.:angel

Jump f1k25 relay and at the pump check red wire = battery voltage, brown wire = 0V.

 

[WE47B1ME]

This is not religious subject.:angel

Jump f1k25 relay and at the pump check red wire = battery voltage, brown wire = 0V.

Ah ha. I was overthinking it

Came up at 11.6v at the pump after jumping and measuring, so we gotz power there.

I pulled the "new" pump motor off, and decided to look at the brushes. Whaddya know.

As I'm quite used to saying this to my wife, "you're right, I'm wrong, I'm sorry" :grin

 

[art_arev]

This is were we say - we told you so....

Look at it on the bright side. You can fix both motors at the same time......Keep one as a spare.......

 

[WE47B1ME]

This is were we say - we told you so....

Look at it on the bright side. You can fix both motors at the same time......Keep one as a spare.......

Thanks everyone as always.

 

[Witek_M]

Ah ha. I was overthinking it

Came up at 11.6v at the pump after jumping and measuring, so we gotz power there.

I pulled the "new" pump motor off, and decided to look at the brushes. Whaddya know.

As I'm quite used to saying this to my wife, "you're right, I'm wrong, I'm sorry" :grin

You have not finished checking it. What's the voltage at brown wire?

 

[WE47B1ME]

You have not finished checking it. What's the voltage at brown wire?

I was getting 0v -- isn't that right?

 

[Witek_M]

I was getting 0v -- isn't that right?

You have not stated this.