P0003

[P0003 0]

My '06 has recently started showing P0003. It also has an issue shifting up from 3rd to 4th, 4th to 5th, and 5th to 6th in automatic mode. In manual it shifts fine. It appears there's some reduction in fuel delivery because getting on the highway is hopeless... unless you want to go nice and slow.I've found a few posts around the internet saying P0003 is a generic code which could mean anything. There are also a few saying it may be "fuel volume regulator control circuit low".Has anyone else encountered this and may have some advice on how to proceed?

[yow2013 0]

I don't believe the 2005 & 2006 Smartcars shifted automatically from 5th to 6th gear. Gears 1 to 5 should shift automatically but at a high rpm.If you have any transmission issues, check the health of your battery. Not just that it is charging, but it holds a charge. Smartcars can deal with a dead battery but not one that is slowly dying. If you need to change your battery, change it and then take your car to the dealer and ask them to "retrain" your transmission.I had problems with my 05 Smart for a few years until I came across an article about the battery. The dealer didn't think this was the issue but once I changed the battery and had the transmission retrained, I haven't had a problem with the transmission since.

[FlossyTheSmart 81]

Yes, it will shift to 6th, especially in auto. It sounds like you might be in limp mode - Are you able to go above 3000 RPM? If not, your EGR might be clogged.You say there are "issues" shifting in auto mode. Are you just saying it doesn't want to do it, or that it has some problem when it tries to actually shift? If you're in limp mode, as described above, it might simply "not want to" upshift.I can't say I've seen anyone get P0003 before.

[P0003 0]

I don't believe the 2005 & 2006 Smartcars shifted automatically from 5th to 6th gear. Gears 1 to 5 should shift automatically but at a high rpm.If you have any transmission issues, check the health of your battery. Not just that it is charging, but it holds a charge. Smartcars can deal with a dead battery but not one that is slowly dying. If you need to change your battery, change it and then take your car to the dealer and ask them to "retrain" your transmission.I had problems with my 05 Smart for a few years until I came across an article about the battery. The dealer didn't think this was the issue but once I changed the battery and had the transmission retrained, I haven't had a problem with the transmission since.

Thank you for your suggestion. Prior to this error code being shown it would indeed shift from 1-6 without much issue. It wasn't the nicest, most comfortable shift... but it shifted.

[P0003 0]

Yes, it will shift to 6th, especially in auto. It sounds like you might be in limp mode - Are you able to go above 3000 RPM? If not, your EGR might be clogged.You say there are "issues" shifting in auto mode. Are you just saying it doesn't want to do it, or that it has some problem when it tries to actually shift? If you're in limp mode, as described above, it might simply "not want to" upshift.I can't say I've seen anyone get P0003 before.

Your post is loaded with useful ideas... rock on! You made a great guess at the 3000RPMs. I went out for a stroll just now and both automatic and manual stop at 3000RPM. It goes a pinch above if you're going down a hill, but there's no way to get it up past the 3000. I found a guide on cleaning the EGR on http://smartcar.hostei.com/SMART_EGR_Valve.htm Does this look accurate? If so perhaps I'll attempt this with the help of my mechanic friend later today.As far as the issue with the shift, it simply doesn't like to do it (it's not impossible). Occasionally it will jump from 3rd to 4th, or 4th to 5th but there's no chance on this earth it'll move itself from 5th to 6th. In manual you can go between all gears it's just a matter of being able to actually use them. Generally speaking hilly areas are interesting as you'll be moving along like a slug compared to any other vehicle. I recall it being quite zippy previously.

[FlossyTheSmart 81]

Yep, those are the instructions. I'd say give that a go. Once you've cleaned it out, you should be able to go over 3000 again, and I bet the shifting will start working as expected again

[Alex 21]

Best/easiest way to do a routine clean-out of the EGR.

Towards the end are a few links to other EGR threads.

[Leadwing 565]

Once you get the ERG issue sorted out, if you don't already have it done, getting the car re-mapped might help lower the RPM's that the car shifts gears in automatic mode. Although I rarely use it, when either of my smarts are in 'auto', they shift to the next higher gear at a touch over 2,500 RPM when accelerating easily. More aggressive driving will raise the shift-point RPM's a bit.

[smart65 28]

That's funny, my remapped smart shifts at about 3100 RPM in auto.

[P0003 0]

Well I just got back from the shop and my EGR is all nice and clean... but I've still got the shifting issue+3000RPM max. The CEL came on immediately when reversing off the lift.Also lubed up the wastegate while I was down there. That appeared to be in good working order!But now I'm stumped and back with a P0003 error code. Drat. Any other ideas?

[Francesco 71]

That's funny, my remapped smart shifts at about 3100 RPM in auto.

Mine too. Perhaps the one that shifts lower is based on the 451 maps (the 45 hp version that does indeed shift at lower engine speeds)? Again, none of the remaps I've seen do this, just as none of the ones I've seen offer EGR deletion. AFAIK, Mark Malone's smart maps don't offer these features, and right now he's one of only a couple of custom mappers for smarts in North America.

[FlossyTheSmart 81]

Time for some stupid, maybe obvious questions:

-Did you clear the codes after cleaning the EGR?

-Did you make sure the EGR electronics were reconnected again?

-Did you verify that the flapper in the EGR was moving freely while you had it out?

Apparently a slow clutch actuator can cause limp mode as well. Maybe try lubing it?

EDIT: Another question, regarding the P0003 - What are you using to read that code?

[Francesco 71]

Your edit was going to be my next question. Much better would be a Star code readout.

[Alex 21]

I'm very suspicious of that PO003 code. Some aftermarket code readers can miss or misinterpret some MB specific codes. I wonder what a true STAR would say about it. It would be weird for a malfunctioning EGR to set off some code no-one has ever seen yet not trip the usual EGR codes. The PO003 itself seems to do with the fuel pressure, but not the high pressure side. I don't think it should apply to a smart CDI. I think a better code reader would say something else which would guide you in the right direction.A good stab in the dark would be to clean and reseat all the engine wiring plugs, inspecting the wiring somewhat as you go. Just a hint of corrosion on connectors can cause all kinds of spurious signal faults. I've often seen weird problems disappear after just reseating connector plugs. Spray them with contact cleaner and seat/unseat them a few times, lube any stiff seals and boots with dielectric grease. (Or vaseline)

[P0003 0]

Time for some stupid, maybe obvious questions:

-Did you clear the codes after cleaning the EGR?

-Did you make sure the EGR electronics were reconnected again?

-Did you verify that the flapper in the EGR was moving freely while you had it out?

Apparently a slow clutch actuator can cause limp mode as well. Maybe try lubing it?

EDIT: Another question, regarding the P0003 - What are you using to read that code?

I'm all for "stupid" questions. I ventured on to this forum in hopes of connecting with a group of knowledgeable and helpful individuals... so far I'd say you've met and exceeded that!!

In answer to your follow up questions:

1) We reset the code and then pulled the (-) battery prior to performing the work. The CEL came back on literally as it was backing out of the garage. It has been reset twice more in the last day since the cleaning and continues to come back with that pesky P0003.

2) The connector seemed to go back on without any trouble:

3) When it was out we separated the solenoid from the valve. The solenoid appeared to have a little piece stuck out via a spring or magnet which could pull itself back in about 10mm or so. It could not be pulled out. The valve portion had a little spot which it pressed on that also travelled about 10mm (guessing at the distance. Didn't have a calliper). There was quite a pile of thick black gunk inside which took a good 15 minutes to clean out and a few cans of cleaner. Eventually it ran clear and nothing more was reachable by pick or brush.

4) The codes were scanned and cleared using a few different scanners including SOLUS Ultra; Torque Pro for Android with a bluetooth ELM327 ODBII reader; and a ScanGauge 2. They all show the P0003 code and were able to clear it. I vaguely recall the SOLUS showing another code about a lightbulb... but I figure that was unrelated. Replaced one of my marker lights while the bumper was off.

The clutch actuator, module clutch, and release system (names taken from my dealer invoice) were just replaced 4 months ago. I'll see if I can find it though and get a little lube in there!

[FlossyTheSmart 81]

Hmm, at this point, I'm pretty much out of ideas, but not completely. In your picture, I noticed the braided hose wasn't tied away from the rubber one leaving the EGR. Has the braided hose rubbed a hole through the rubber one?Other than that, I would say you need to get scanned by a STAR system. They'll have it at the Halifax dealer, or maybe a good Mercedes independent will have one. Can't say for certain if that will actually provide anything useful though.

[Alex 21]

It's not the EGR! PO003 (even if real) doesn't point to the EGR.

New clutch etc a few months ago, that means the engine was dropped.

Wiring is more suspected knowing it has been moved around. I go back to my well-aimed "stab in the dark" of cleaning all the engine wiring harness plugs and inspecting the bundles. Without great difficulty you can unplug the entire harness, move it up above the engine and lay it out for careful inspection. Read through the three bars of death thread, the post I linked to shows the harness laid out. Earlier in that thread is more details.

A true STAR readout would be helpful, I'm still suspicious of that PO003, pretty sure I've never heard of it on these forums I don't think a smart should be able to trigger that code and I suspect a STAR would read it differently.

[Francesco 71]

It's also well documented that the smart's OBD isn't 100% CAN-compliant, and that it doesn't play nicely with Bluetooth and USB widgets suck as Elm and the like. Is the ScanGauge seriously reading a PO003 code?

[P0003 0]

It's also well documented that the smart's OBD isn't 100% CAN-compliant, and that it doesn't play nicely with Bluetooth and USB widgets suck as Elm and the like. Is the ScanGauge seriously reading a PO003 code?

You bet, more P0003 fun! It was the version 2 purchased from the manufacturer with the latest firmware about 2 months ago.

[P0003 0]

Hmm, at this point, I'm pretty much out of ideas, but not completely. In your picture, I noticed the braided hose wasn't tied away from the rubber one leaving the EGR. Has the braided hose rubbed a hole through the rubber one?Other than that, I would say you need to get scanned by a STAR system. They'll have it at the Halifax dealer, or maybe a good Mercedes independent will have one. Can't say for certain if that will actually provide anything useful though.

That missing cable tie was due to use being in there messing around. We ended up removing the intercooler fan temporarily and snipped that tie to get some extra play with the harness.

[Francesco 71]

As an aside, contact the manufacturer of the ScanGauge and tell them you have a 450 smart, they will send you a modified OBD cable that works with the smart's wonky CAN bus.

[P0003 0]

perhaps a fuel regulator , electronics side failure ? or bad connection at the plug ? or trace the cable back to check for shorts to ground ?

The code on the SOLOUS a the suggestion about replacing the fuel regulator solenoid. Is that what this part is? Seems like there's 2 or 3 different names for every part. They also mention there being the potential for collateral damage when installing this... have you seen any pictures that show where this one is located?

[Alex 21]

The fuel pressure regulator is not likely, imho. If it were, it either wouldn't start, or it would show at least one very specific code of low fuel rail pressure. Leave the fuel system alone! That is almost certainly not the problem. (At least not a problem until it gets messed with...) I still think a proper STAR code reading would be very helpful.

[P0003 0]

The fuel pressure regulator is not likely, imho. If it were, it either wouldn't start, or it would show at least one very specific code of low fuel rail pressure. Leave the fuel system alone! That is almost certainly not the problem. (At least not a problem until it gets messed with...) I still think a proper STAR code reading would be very helpful.

Please forgive my ignorance here... but what is "STAR"? Is that a Mercedes-specific thing, or can any higher end automotive dealer access this thing?

[FlossyTheSmart 81]

Other than that, I would say you need to get scanned by a STAR system. They'll have it at the Halifax dealer, or maybe a good Mercedes independent will have one. Can't say for certain if that will actually provide anything useful though.

It's a special computer system for all diagnostics on smart and Mercedes products. As mentioned previously, the dealer will have one, and a good Mercedes independent might (You'd have to ask).