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My brake control board, wiring harness, and vacuum pump failed about 4 months ago and were replaced under warranty. Some of the postings about the failure and repair hinted at a known issue with chafing on the wiring harness eventually leading to a short in the wiring that cause the whole subsystem to fail.

I was never able to get more info about the location of the wiring and what we might do to prevent the short from happening. Is anyone on this excellent sub-forum aware of this issue and can suggest where on the car I might be able to apply some preventative measures?

Thanks in advance, RG
 

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Unless the ED brakes are markedly different than the ICE version (don't think they are) this would potentially apply to all smarts of your model year.....

Did you report the issue to the NHTSA as a safety problem? I don't recall seeing the whole brake system failure mentioned before. :)
 

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Unless the ED brakes are markedly different than the ICE version (don't think they are) this would potentially apply to all smarts of your model year.....

Did you report the issue to the NHTSA as a safety problem? I don't recall seeing the whole brake system failure mentioned before. :)
The ED brakes are the same except that they use an electric vacuum pump instead of engine manifold vacuum to provide the power assist. While a failure of power assist (brakes or steering) should not be considered something dangerous, it seem that in these days of a low-skill driving populace it is - such as those Chevy keyswitch defects causing fatal accidents simply from power steering or braking going of when the engine shut off.

I suspect in the case of a 2000 pound Smart ED, braking is still easy without power assist but I haven't tried it yet.

But yes, I think that NHTSA should definitely be investigating this. Rob should contact NHTSA. Presumably they have a consumer complaint site...
 

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My brake control board, wiring harness, and vacuum pump failed about 4 months ago and were replaced under warranty. Some of the postings about the failure and repair hinted at a known issue with chafing on the wiring harness eventually leading to a short in the wiring that cause the whole subsystem to fail.
Yes. My A/C failed due to wire harness chafing. While they replaced the compressor, I'm not sure it actually failed or it was a wrong initial diagnosis. They did not replace the harness, but only found the chafing point and spliced the worn-through wire. I hope they did something about the harness chafing too.

They also replaced the charging receptacle and its harness - claiming in a follow up inspection that it was wearing through somewhere. They weren't able to provide me with the old harness though - claiming that it was already thrown out. I tied the new charging harness clear of any possible rub points myself when I got home.

Presumably, what car syatem fails is entirely dependent on the particular wire in the harness that gets worn through.

I will call my dealer and ask if I can talk to the actual service technician who did the repair to find out where this chafing point is - hopefully he will remember.

Chafing wiring is something I's expect in a Chinese or Russian car, not a German one.
 

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Unless the ED brakes are markedly different than the ICE version (don't think they are) this would potentially apply to all smarts of your model year.....

Did you report the issue to the NHTSA as a safety problem? I don't recall seeing the whole brake system failure mentioned before. <img src="http://smartcarofamerica.com/forums/images/SmartCarOfAmerica/smilies/tango_face_smile.png" border="0" alt="" title="Smile" class="inlineimg" />
The ED brakes are the same except that they use an electric vacuum pump instead of engine manifold vacuum to provide the power assist. While a failure of power assist (brakes or steering) should not be considered something dangerous, it seem that in these days of a low-skill driving populace it is - such as those Chevy keyswitch defects causing fatal accidents simply from power steering or braking going of when the engine shut off.

I suspect in the case of a 2000 pound Smart ED, braking is still easy without power assist but I haven't tried it yet.

But yes, I think that NHTSA should definitely be investigating this. Rob should contact NHTSA. Presumably they have a consumer complaint site...
No, braking without the assist wasnÂ’t easy. I waited until late at night to drive the vehicle to the dealer so I could minimize the chance of an accident by driving when there was no traffic.
 

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Discussion Starter #7
Unless the ED brakes are markedly different than the ICE version (don't think they are) this would potentially apply to all smarts of your model year.....

Did you report the issue to the NHTSA as a safety problem? I don't recall seeing the whole brake system failure mentioned before. <img src="http://smartcarofamerica.com/forums/images/SmartCarOfAmerica/smilies/tango_face_smile.png" border="0" alt="" title="Smile" class="inlineimg" />
The parts that failed only apply to the ED - the electric vacuum pump, the associated computer control board, and the wiring harness.
 

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Nice snark. Did my point about quality-control reputations of various countries really go over your head? Making a wiring harness that does not destroy itself from vibrations is not exactly rocket science...
 

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Very interesting! The frame on the right side of the engine compartment is also where the charging receptacle wiring on my car were also found to be chafed in addition to the unspecified wiring harness chafing that disabled the A/C.

After I got the car back, I secured the charging wire harness better by tying it to the stiff A/C refrigerant lines that go through this area so it is not rubbing on the car frame.

I think is it time to issue out own "service bulletin" and recommends every ED owner check all wires that are routed along the right side of the engine compartment for wear.

The service guy (or gal) wrote quite a detailed report. I wonder if all MB service tech's do that. I'll see if there is comparable documentation for my car.
 

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No, braking without the assist wasnÂ’t easy. I waited until late at night to drive the vehicle to the dealer so I could minimize the chance of an accident by driving when there was no traffic.

Prev to my cars full shutdown, I had a crash sensor and brake system code in the system, but no affect on car or performance.
 

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Very interesting! The frame on the right side of the engine compartment is also where the charging receptacle wiring on my car were also found to be chafed in addition to the unspecified wiring harness chafing that disabled the A/C.

I think is it time to issue out own "service bulletin" and recommends every ED owner check all wires that are routed along the right side of the engine compartment for wear.
With ED representing such a small production run the few reports of chafing on SCoA is alarming! Has anyone filed with the NTSB or the likes to raise the awareness and perhaps trigger a TSB or Recall?


This link will get you started . . .

https://www-odi.nhtsa.dot.gov/VehicleComplaint/
 

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My last visit gave me a 9 page report, nyc dealer only tried to sell me tires
Another question... what do you think the tech who wrote the report is calling the "right side trunk panel" By "trunk" I assume he is referring to the space behind the seats and by "panel" is he referring to the interior right trim, or the outer body right quarter panel? I recall they told me that they had to remove the quarter panel to replace the charging recptacle/harness unit, and also, possibly, repair the harness to the power control unit.

So, to fully inspect this part of the wiring harness, some body disassembly may be needed.
 

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I had some time today so I poked around in the engine compartment and underneath as well. I didn't see anything really worrying in my ED that has done 12.5k miles in 17 months since I purchased it with 10 miles on the odometer.

What I did see was a cable on the right (passenger) side that was pressed against a tube and wearing the insulation a bit. I put on some split loom tubing to protect it. Here are before and after photos. This is from the rear of the smart looking forward. This area is on the right, pasenger side of the motor bay.





From underneath, to the right side of the motor, are wire bundles that are exposed. They don't chafe on anything, but could potentially be damaged by snagging something while being driven. I didn't really have a better alternative than to just put some split loom tubing on it - that won't protect it if I really catch something heavy but it should keep the wires in better shape from gravel and rocks.

Again, before and after:





Sorry for the changing perspective on these last two pictures - it was hard to take a cell phone pic with the limited room I had underneath. The exposed wires are at the far right in the "before" picture, and are centered in the "after" picture after I put the split loom tubing on.
 
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