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Discussion Starter #1
So I took my 2005SL 500 to my Indy. It came back with codes that the SBC unit needs replacing. So I had it towed to the dealership seeing it’s covered under a 30 year warranty.

Unfortunately he cleared the codes, and the dealership needs to see them in order to replace the SBC under warranty. Is there anyway to recreate the codes without driving the vehicle until they come on again? That’s really a risk I’m not willing to take.
 

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I doubt the dealership is going to do anything unless they can prove the fault for themselves.
 

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Discussion Starter #4
I doubt the dealership is going to do anything unless they can prove the fault for themselves.
Yes they will not. That’s basically my dilemma. It’s completely unsafe for me to drive the vehicle until the codes come back on. I’m looking for a quick way to make this happen, as it would be a serious risk for me and others to get back on the road with this vehicle.
 

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Have you driven the car since this happened? If so, were the brakes good? If good, then you may have an intermittent issue with the motor for the SBC pump, or a failed SBC accumulator.

A failed accumulator means the pump will need to run more often, or continuous, but the brakes work fine.
A failed pump or motor means no pressure in the SBC, and you will need to mash the brake to the floor to get the weak backup system to stop the car.
Either failure will trigger the brake warning, and put the code back in the system.

I suppose it is possible to do this while sitting in the garage with the car running, but it may require driving it. If driving, drive cautiously and don't tailgate in case you get a pump failure.

An example - I had a brake warning, and found no specific issue, and kept driving it. 1000 miles later it came back, and the issue was the SBC accumulator. In the 1000 mile period, the 30 year warranty came out for the SBC, so I took the car to the dealer and they only replaced the accumulator. I was hoping for the total SBC module replacement, but they said the motor and pump are fine, and they are correct. Down the road it will eventually fail the motor or pump, and I'll get a total replacement at that time.
 

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Discussion Starter #6
Have you driven the car since this happened? If so, were the brakes good? If good, then you may have an intermittent issue with the motor for the SBC pump, or a failed SBC accumulator.

A failed accumulator means the pump will need to run more often, or continuous, but the brakes work fine.
A failed pump or motor means no pressure in the SBC, and you will need to mash the brake to the floor to get the weak backup system to stop the car.
Either failure will trigger the brake warning, and put the code back in the system.

I suppose it is possible to do this while sitting in the garage with the car running, but it may require driving it. If driving, drive cautiously and don't tailgate in case you get a pump failure.

An example - I had a brake warning, and found no specific issue, and kept driving it. 1000 miles later it came back, and the issue was the SBC accumulator. In the 1000 mile period, the 30 year warranty came out for the SBC, so I took the car to the dealer and they only replaced the accumulator. I was hoping for the total SBC module replacement, but they said the motor and pump are fine, and they are correct. Down the road it will eventually fail the motor or pump, and I'll get a total replacement at that time.
When it happened had to press brake all the way down to stop it at a few mph. Honestly not sure that completely stopped it as I put in park and threw the parking brake on.

See all the codes above in my first reply-points to complete SBC failure. Scared to death to drive it all. The tech at the dealership said he wouldn’t let anyone there drive it either, as he saw fluid on the ground (he assumed it to be brake fluid).

I have sent a message direct to Mercedes-Benz, but I’m not holding my breath. I suppose I will just turn it on and continually mash the brakes hoping the lights come back on?

My Indy seemed certain it was SBC pump, and he suggested not driving it anywhere. Kind of stuck here. If I had been going more than a few mph there would have been no way to stop the vehicle.
 

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That is an SBC motor or pump failure...the worst kind. Likely the motor quit for a while, as it sounds like the brakes work now, and the dealer was not able to replicate the issue. Could be bad brushes, dirty contacts, sticking pump. Who knows.

I would do the garage test for a number of applications and see if you can get it to come back. Otherwise, you have to drive it and wait until the issue happens. If you are afraid to drive it, you have to sell it! Last option - replace the SBC motor using money from your own pocket. You might be able to plead for a reimbursement from MB after replacement.
 

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Discussion Starter #9
That is an SBC motor or pump failure...the worst kind. Likely the motor quit for a while, as it sounds like the brakes work now, and the dealer was not able to replicate the issue. Could be bad brushes, dirty contacts, sticking pump. Who knows.

I would do the garage test for a number of applications and see if you can get it to come back. Otherwise, you have to drive it and wait until the issue happens. If you are afraid to drive it, you have to sell it! Last option - replace the SBC motor using money from your own pocket. You might be able to plead for a reimbursement from MB after replacement.

Thank you for the responses, they are much appreciated.
 

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If you can lift the car and put it on jack stands, you could run it in gear and keep applying the brakes until your codes reappear, or until it falls off like Ferris Beulers friends Ferrari and goes out the window! Hmmm. Maybe rest it on railroad ties front and rear. Might have to spin the front wheels too. Maybe spin them backwards too, that might generate a code or two. That's all I've got.
 

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I went through the process of getting the pump replaced a few months ago, under warranty. The warning light (and brake power loss, and presumably codes) occurred luckily always very shortly after starting the car, never while driving at speed. In addition, it occurred when I had to pump the brake pedal several times because e.g. I had to pull back and forth a few times in order to get out of a tight parking spot, our out of my garage etc. That seems a "safe" way to force the issue to show up.
 
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