Today I noticed my engine temp unusually high (230), and it does not sound like the fan is cycling. I did not have time to really investigate today, but will be checking to see if fan is locked up, or if it may just be a temp sensor. Anybody have any experience with this? Where is the fan temp switch?

Meantime, I turned the heater on full blast, which brought the temp down to reasonable levels so I could get it home.


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Check the fuse for the fan circuit. You will have to look up the fuse number in the owner's manual. Also, if you turn on the A/C, the electric fan should turn on. I hope it is not the fan unit itself, as the front clip has to be removed and the A/C condenser and radiator also has to come out to replace the fan. The sensor should be near the fan. Follow the wires and make sure the connector is tight. Let us know what you find is causing this concern.

A couple of years back one of the smart USA techs disclosed that the high temperature light (red light on the instrument panel) will come on at 244 deg. F. He also stated that the head gasket will fail at 248 deg.  You are still below those numbers but the smart has a very low tolerance for high engine temps - if the light comes on, stop the car immediately or you could be looking at a new engine.

Wow, not enough room to get a hand in to even try to spin the fan. It definitely is not operating so I will be getting it in to a local mechanic that is familiar with smartcars. I will not be going to the MB/smart dealer, as I have had two very bad experiences with them.

Good to know the temp info, jwight. The light did not come on, as I usually keep a close eye on the temp. I installed a scangauge top and center of the dash, and always monitor rpm's, engine load, voltage, and engine temp.

It is surprising that there are only a few degrees from warning light to head gasket failure. Most people will not notice the light right away, let alone actually turn off the engine immediately.

The heater fan actually does a very good job of keeping the temp under control, but I hope I can get it in the shop within the next couple of days. Not looking forward to the expense, and am very disappointed at only 34,000 miles.

My daughter hit that magic number we bought a new motor light went on and she called me and that was the end . Don't have answer why but anti freeze was in #2and3cyl daughter got a new smart city edition and I got the 2008 I'm happy and she happy guess that's all that counts

Antifreeze in #2 and #3 due to head gasket failure.  Sounds about right if the temp light came on and the engine was badly overheated.

Well, after waiting several weeks for the first available schedule opening, the car went in and, sadly, I was correct. Grand Total: $1104.04 to replace the electric engine cooling fan. I ended up having to take it to the local MB dealer, as my other smart mechanic didn't want to tackle it without access to the "Star" diagnostic system. At least this time I did get a free loaner vehicle for the 9 days they had the car. As usual, they had to order parts from the stock in house.

The new smarts definitely feel better...suspension wise, shifting wise, and all the new "auto" controls (lights, wipers) are nice. I might consider trading in for a new model, but am very disappointed in the maintenance costs for the vehicle (currently 35,000 miles on the odo).

I highly recommend all smart owners to have a scangauge or other gauge to monitor engine cooling water temp, and actually check it periodically. This could have been catastrophic if I had not noticed the temp climbing unusually, and investigated long before any stock warning light would have come on. 

Also, a good lesson for emergency repair....I was able to drive the car for several weeks before getting it in for the service by monitoring the temp and using the heater fan for extra engine cooling when in stop and go traffic. It was not very comfortable, especially here in the tropics, but the engine temp never went above 210f while operating this way. 


beachbum, you might also want a head temp guage like the Koso tiny guage and  sensor that fits the spark plug as a washer.  Smart is a design flaw.  If any gas gets into the water passages from a tiny gasket leak, that increasing bubble has no way to go DOWN under the cabin to refill the head with coolant unless you drive it hot up a very steep ramp so the engine is lower than the piping to the front radiator.  The head can empty itself as the gas leaks in and result in no cooling in the highest cyl, which I think eats engines worse than the tiny compartment under the carpet.  When my guage climbs, I drive up a steep bank beside my driveway and the coolant recovery tank level drops when the bubble burps the little pig.....

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