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Hello, I have a 2000 450 diesel smart (city-coupe). Today I stopped the car after a 1-hour drive and 5 minutes later the engine was not starting. The starter motor was working perfectly, but the engine was not starting. Not hearing the noise of the fuel pump when the key is in position 1, I checked the wires in the fuse/rele' box under the left seat (see FQ101 guide). I noticed that the fuel pump wire is kind of melted (connector H-LS I pin 2). See the pictures below. With a 10 A fuse-protected wire from the cigarette lighter, I provided 12 V and the car could start. Then I drove home (1 hour again). Now I've cleaned the "burned" connector and the car seems to work properly without the external 12 V. I am also going to replace the fuel filter (was not old though). QUESTIONS: - While driving back I could not disconnect the external 12 V, otherwise the engine would switch off. Is normal that the fuel pump is always active while driving? - What do you think happened? Should I measure the Amperes that the pump uses to see if is working properly? - Where can I buy the crimps to replace the bad ones? Do you know how to replace them? - Does someone have the ECU pinout for the diesel version? I could only find the petrol ones on Evolution Thank you.

I have a 2006 fortwo diesel that my son basically did a full rebuild on. Cylinders, pistons, rings, timing chain and guides, valves, starter, alternator etc. Most it was for fun. But suddenly this week the car has lost all power. It will fire up and idle for about 20 seconds and then just dies. You can't move it at all. Since we are getting power to the fuel pump we think the fuel pump is just done. So I figure I'd replace the pump and filter right away and maybe the crank sensor if its accessible? BUT I've been searching for a place that sells fuel pumps and haven't found anything. Where are you guys, ordering things from? Any places in Canada?

Hello all, I've been leaching knowledge from this site for many years but have never actually made a post! I'm hoping somebody might be able to come up with something obvious that I'm missing, here's what's going on: My 2006 Smart Fortwo CDI started intermittently stalling when decelerating to a stop and occasionally when accelerating from a stop. When I put the scanner on it I get P0087 for low rail pressure/fuel system pressure. I've done the following: • Replaced fuel filter • Had the wife turn the ignition on while I held a disconnected fuel line in a bottle • Pulled SAM unit out, inspected plugs but didn't unfold for fear of cracking the old crusty circuit board • Bypassed SAM unit fuel pump relay and set up an external one • Removed EGR and thoroughly cleaned it • Resealed the injection pump with the Bosch CP1 kit You can hear the low pressure pump running with the ignition on. It runs constantly though and I never noticed if it did before or not. Some things that I was considering doing but haven't yet are: • Remove and inspect/clean the fuel pressure sensor (I read that it has a screen that can get clogged) • Dropped the fuel tank to remove and inspect/test the pump Has anybody been down this road with theirs before? Mine is a convertible with 130,000km on it and was honestly the best performer out of the three I've had up until this point. I appreciate any direction and apologize for my first post on here being a "help me please"!

2005 diesel has a weird noise coming from SAM. attempted to start a few weeks ago and it was trying to start and just shut off and started making this arcing noise. A few months ago I had the normal issue with the connector melting that goes to the fuel pump, I bypassed that and solved that issue. Shortly after that similar issue this time it was a bad ground running to the fuel pump so I fixed that with a new ground. I’ve checked continuity on the ground and it’s good. Fully charged the battery and that’s good. When I move the new connection I made for the fuel pump to a different fuse location the fuel pumps comes on and you can hear it pumping no problem. But you plug it back in where it goes and the noise starts back. So the fuel pump can get power and the ground is good. It’s just that fuse slot for it is where the problem lies. 61100904286__2ECC9F88-DE63-4870-BDFB-380EDB43FC10.MOV

My 06 450 just decided not to start. Turned over fine, but no fire. Glenn (Smart142) said: If its turning over and not starting I would check to see if its getting fuel. Easy to do. Disconnect the line to the common rail with a 14mm wrench. Turn on ignition and see if fuel is being pumped. I did that, and he was right. Then he gave me the cure: ']The problem is electrical. The relay in the SAM is gone. I'm 99% sure. My solution is very inexpensive if you do the repair yourself. Elevate the rear end and remove the rear belly pan. On the passenger side you will see the fuel tank - there is a bundle of wires going to it. Find the 2 thickest wires. One will be brown - cut it and then solder in a wire and run it to the frame for the ground. Cut the other one and add about 8 ft of wire. Run it to the drivers side - locate a rubber grommet. Poke the wire through that - it will come out under the carpet beside the drivers seat. Run that under the carpet and up to the SAM. Add a female connector to the wire. Connect a 10 amp fuse to it. On the left side of the SAM you will see 2 wires connected. Those are the switched connectors. Insert the other blade of the fuse into the connector beside those 2. Turn on the ignition and you should hear the pump running. If you hear it run the smart should now start. If it does you can leave it as is or add a relay to the circuit This fix has worked for me a number of times over the last 5 years. If you aren't able to do the repair yourself you could show a mechanic who could do it in a bout 2 hours max. The alternative is buying a new SAM from the dealer and having it programmed.'' I did the electrical work-around, but it still did not fire. Still no fuel at the rail. It took me a few days, the purchase of a new fuel pump and dropping the fuel tank before I noticed that I had soldered the wrong ground wire to the ground. Removing the tank, I put power to the pump and it worked. I attached the connector to try that, and noticed the orphaned ground wire hanging from it. Boy, was I embarrassed and felt stupid! I got it all put back together and grounded the right wire, and she is purring again. I do love this car! I need to give a hats off to Glenn for an excellent patch around the fuel pump relay. Thanks, Uncle Glenn. I learned a few pitfalls to watch out for when dropping the fuel tank. If anyone is interested, I'll add a post on that.

Hey Gang. Glenn suggested I work around the fuel pump relay, but when I did it still gives no fuel. I put power directly to the pump, and nothing. Anybody got a parts car, willing to part with your fuel pump? 2006 450 cdi. Tedder in Brockville

I was driving from Williams Lake to Vancouver. I stopped to fill up with fuel in Hope, and then my car wouldn't start. I had it towed to Vancouver Mercedes to have it looked at. I had a standard maintenance to do anyway. They said that the fuel pump failed electrically, and burned up the wiring bundle. To repair this, they need to replace the fuel pump, the wiring bundle. Since the wiring bundle is attached to the SAM, it has to be replaced also, which in turn, means programming new keys. The ESTIMATE for all this is $3400. Does this sound correct to you? can you give me any thoughts? I have standard maintenance, and a couple of other repairs, so the total is looking like $5000, and that means the car might have to go to the auto recyclers. I'd really like any advice from the Smart car club folks. Thanks, Tony

Well, it's my turn I guess. The car is a 2006 CDI, and it's relatively new to me. I have done external relays for the headlights, the starter motor, and the fuel pump. I have been doing quite a bit of work on it (starter motor, fuel filter, external relays, front springs, intercooler) and just a month ago I started using the car every day. I have put about 700 kms without any issues at all. Yesterday after stopping at a store for some bolts, the car cranked over and started really rough, like running on 2 cylinders. It ran like that for about 5 seconds, and I shut it off, afraid it would damage something internally. When I tried again, it cranked and did not fire up. Kept trying several times, without luck. I need to mention here that the entrance to that store is gravel, and full of potholes. I drove in slowly trying to avoid the worst, but maybe something was shaken loose, I think. Called CAA for a tow, and after waiting 5 minutes or so, decided to give the SAM a wack. The car started on the first try after that. Drove it around 5 kms, and when I was just about at my driveway, the engine suddenly quit running as I started out of a stop sign at the corner. With some help, I pushed it into my driveway. Today I was getting ready to do some troubleshooting and on my first try it started right away. Tried about 5 more times successfully every time. I just tried again (following day), and it started fine. I just found out that I put my relay on the wrong wire out of the brown connector, #9 instead of #10. I'm going to fix this, and install a bypass toggle switch on it. I will also clean the pins on the SAM unit and put dielectric grease on everything. Wish me luck. Any help with this would be greatly appreciated.

This is kinda weird. This has happened a few times in the last couple days. I'm driving my car, everything is fine. I park and turn the car off to go into a store, come out and it will turn over but wont start! It turns over quickly, no sputtering or anything, and doesn't sound like the fuel pump is working. But I leave it for a bit and try it again, and it fires up fine and no problems running. Today it ran fine all the way to work, I parked, turned the car off, and immediately tried to start it and nothing! Turns over, wont start. And if I try to shift while the key is turned, it shows O on the display. It wont go into gear or reverse while this is happening. I'm sure this has happened to someone before, but I cant seem to find a post about it. Any suggestions?