[pmaf.iphone]

I bought a new one from Mercedes for €160 and paid €50 to have it coded in a workshop with online access

 

[FalconFour]

Well, I got the new ECU today! It didn't need coding. It just dropped right in and the car started right up.

...

Started right up, for a few seconds without faults (yay! Happy, clean dash! No fault light!). And then, about 10 seconds after "run" while getting happily excited that there's no faults... "Malfunction - visit workshop". AARGHHHH...

Same exact problem. Same exact code. Same everything - no Cruise (can turn on, can't "set"). Drives fine, cools itself just fine. Well, the saga continues.

Now what? I think I need to find wiring diagrams and start digging into whether there truly are two pumps, one of which may have failed while leaving the other working fine. Seems odd, but I can't get a clear picture of what really is in this car (while it's mixed-up with its evil twin, the gas version of the 453). And I don't have a lift to easily and freely mess-around with stuff, so I really need to get advance information/research before digging into the car - especially if I want to keep driving it while figuring it out.

 

[pmaf.iphone]

Are you sure the NEW ECU is good?
I think is not

You can check rear pump when the car is charging:
Put the hand on it to feel if it is working
You can see the coolant running in the expansion tank

Try to find someone with a similar car so you can try an ecu that is good
that's how I did it

 

[FalconFour]

There's a 0% chance that two ECUs in a row are going to have an identical, obscure fault that precisely no other people on the internet have ever reported (I'm the first person to ever write "P0463F1" it seems - the only results are my own posts now). Not only that, but it's the only fault it has. So I can definitely rule out the ECU and I'm not going to focus on it anymore.

I'm going to try digging into wiring diagrams and figure out what wires go where, and hopefully determine if there is more than one pump, where the sense wires go, how it gets its feedback, etc. Just need to find a way to get that info out of the labyrinthian Mercedes service software...

(and yes, the one pump I see is working fine. Under the hood, you can see it diligently squirting coolant into the bottle, circulating normally. It runs, and all the components stay cool)

 

[FalconFour]

I also could be entirely on the wrong track, misled by a bad description of the error code itself - the iCarSoft scanner is the one telling me that it's a coolant pump fault, but Lord only knows where it got those definitions. It could be an entirely different problem (especially since "P0463" is a fuel level sensor fault on Renault cars - and this ECU is a Renault!). The fuel level sensor fault is, obviously, not rational for an electric vehicle though - so it's still got me a bit stumped.

If I could find any other way to retrieve fault codes and definitions, it could at least correlate some sanity if it matches, or disagrees, with the iCarSoft results.

At this point, we really just don't even know if it is truly complaining about the pump, or if iCarSoft is just sending me in circles. If the car itself could use its beautiful full-graphics dash display to display a fault code and/or message, that'd go a long way! Secondarily, maybe there is PC software (a la DDT4All?) or a mobile app that can interface with this beast and get me a second opinion. I do have DDT4All set-up and working (I was able to switch my lock mode to "unlock all doors with 1 press", hooray!), but it was unable to interface with this ECU - possibly because I lack the data file for it.

 

[pmaf.iphone]

"There's a 0% chance that two ECUs in a row are going to have an identical, obscure fault that precisely"
I don't agree, I have 2 EQ smarts from 2017 and they both had the same error with approximately 80 000km
The cars never had any more errors
Here in Portugal there are more smarts that had the same error
With the Mercedes software you can check the insulation resistance, which can be measured with a good ECU and cannot be measured with a damaged ECU.

 

[smc]

@FalconFour Have you managed to make any further progress? I had the same issue start a couple of weeks ago: same warning light, can't select a cruise control speed (or LIM speed). A local, independent garage checked it today used two code readers. One of them said P0463 and the other said P0463F1 - which brought me to this discussion.

I took the rear right side panels off today and my 2018 ForTwo EQ uses the exact same part numbers as yours. I'm waiting to hear for the price of the part from my local Mercedes dealer and the programming cost. But I suspect their reply will be that they want to test it first - I can just see the Euros adding up! My guess is that I'll need to go down the official Mercedes route as my local independent probably can't program a Mercedes part. My guess is that they need to be programmed to suit the particular car they'll be installed in (as you noticed yourself, the same ECU is used by multiple different cars brands).

Please let me know how you get on and I'll also update my own situation here.

 

[pmaf.iphone]

Not need to be programmed to suit the particular car but must be programmed with the latest software

 

[FalconFour]

@smc I'm still in limbo (still all the same original symptoms). Waiting to get a chance to get the car on a lift and be able to inspect the SECOND cooling pump that's behind (/above) the aero panel in the front of the car. I can obviously tell that the power electronics cooling pump - attached to the motor in the rear of the car - is working fine, and coolant is flowing... but the battery loop pump may not be (I think it may borrow/circulate coolant through the power electronics loop, or through a heat exchanger somehow, but not sure how it all works).

Finding a chance to lift the car or get it in a position where I can get that whole aero cover off and be able to poke around under it is the hardest part, so it's taking a bit.

 

[smc]

I left my ForTwo at the local Mercedes dealer today. They said they were able to do a more thorough diagnosis than just an error code read. I got a call later in the day and everything they said was consistent with what's been said in this thread. They read the code and used some Mercedes(?) software to command the coolant pump via the ECU, but it failed. So they were then wondering if it's the ECU at fault (just as we've mentioned here), so tomorrow they'll test the coolant pump with a direct power feed (not via the ECU). If that works, then they'll order a new ECU from Germany. The interesting thing is that they told me that would be ideal because replacing the pump is actually more expensive than replacing the ECU. ..I'm guessing that's because they'd need to refill the coolant again...?

I'll post more updates here when I have them.

 

[FalconFour]

@smc - did they make a distinction whether it's the battery coolant pump (in front, behind the shroud) or the power electronics coolant pump (exposed, attached to the motor in back)? In my case, the coolant is visibly flowing in the bottle under the hood when the car is on or charging, and everything is charging/driving just fine. If the power electronics pump weren't running, I'd expect it'd overheat while charging or driving, and give other issues (possibly damaging other things, too).

My current suspicion is that, since the ECU has two coolant pump circuits, it's that other pump that's legitimately failed, especially since I can't really monitor battery temps (frustratingly, neither my OVMS nor the iCarSoft scanner seem to show battery temps). No way to monitor that pump, control the pump, or get a more clear fault description either. So I'm still a bit blind until I can get under there and look at it.

But yeah, ... replacing the ECU is fairly easy (15 minutes), while replacing that battery pump would be a fair bit more daunting.

 

[smc]

No, they just said, '"pump". I can ask them when I collect the car, though. The new ECU should arrive mid week and I should get the car back by Thursday.

 

[Savvidisgr]

There's a 0% chance that two ECUs in a row are going to have an identical, obscure fault that precisely no other people on the internet have ever reported (I'm the first person to ever write "P0463F1" it seems - the only results are my own posts now). Not only that, but it's the only fault it has. So I can definitely rule out the ECU and I'm not going to focus on it anymore.

I'm going to try digging into wiring diagrams and figure out what wires go where, and hopefully determine if there is more than one pump, where the sense wires go, how it gets its feedback, etc. Just need to find a way to get that info out of the labyrinthian Mercedes service software...

(and yes, the one pump I see is working fine. Under the hood, you can see it diligently squirting coolant into the bottle, circulating normally. It runs, and all the components stay cool)

Εγώ have the same problem P0463F1 I changed 2 woter pump and the same problem ☹

 

[smc]

Just got my car back from the dealer and everything is now fixed. The pump they had tested was the battery coolant pump. The new ECU was 269EUR and its firmware update cost 29.10EUR.

So, from my point of view, @pmaf.iphone was correct. But even if you bought and fitted the new ECU yourself, you'd still need Mercedes to update the firmware for you.

On a side-note, they were able to see that one other Smart had the same issue at some point, but it was dealt with by another dealer in the same chain (not that particular garage). This is because the exact same ECU part number had been ordered and they could also see the job order - which the other dealer had apparently initially been misdiagnosed and replaced the coolant pump... I'm guessing that customer was reimbursed for the pump costs once they realised it was the ECU at fault.

Hope this all helps!

 

[pmaf.iphone]

@smc great, falconfour It's working with the pumps but I think it's the ECU too, he bought a damage one

 

[FalconFour]

i think at this point i have no choice but to go to mercedes and beg for mercy 😭 This sucks. I was hoping it was the pump... something I could actually replace.

Going to ask about how the policy works. If I pay for diagnosis, will it pay forward into repair if I have them perform the repairs? I don't want to pay $200 just for them to look at it, and then another $550+ for them to buy the ECU (inevitably $$$+ more than Euro), and then another $100 for them to program it.

If I could, I'd want them to first try updating/reprogramming the ECU I have. I still doubt two ECUs have the same hardware fault - rather that it may be a faulty detection of an aging pump, that a newer firmware version corrects? Not sure, but if I can ask them to just reprogram/update it to see if that resolves the issue, I'd pay for that.

At any rate, I guess all signs point to feeding the evil Mercedes service monopoly a bit of my money to do something I'd be capable of doing myself, if the tools and information were available like it is with Tesla. Rubs me the wrong way, I tell ya...

 

[pmaf.iphone]

Try to find a workshop with a mercedes online accout

 

[Savvidisgr]

I have the same problem and I can't find solutions

 

[FalconFour]

Try to find a workshop with a mercedes online accout

I'm in the US. No independent shops can work with Mercedes ECUs. They can work with mechanical/electrical/parts, but ECUs are locked behind Mercedes' software which is unobtainable by independent shops, it seems. I called around and got all the same reply - from the few shops that actually work with Smart - that no independent shop will be able to reflash an ECU, and working with ECUs is the one thing that requires a Mercedes service center.

(I could swear this kind of business practice was illegal here - it's surprising Merc hasn't been fined/sued for this)

Unfortunately it means there's no option except to go to a Mercedes dealer.

 

[pmaf.iphone]

mercedes software it is easy to download on MHH auto, vci it is easy to buy on aliexpress, I believe that in America there are thousands of independent workshops with this