SO for a while now, my wife's 2014 Passion hasn't been able to use the AC. when the car has been running for a bit, and comes to a stop light, a loud thunk thunk thunk goes on under the hood. If we attempt to turn the AC on, the same noise happens. I took the hood off today, and got the same result when running the AC. I did note the coolant reservoir was shaking erratically as well, but was definitely not the source of the noise. Does anyone know what this might be? I assume a busted connector or something. 44k miles on it, only had it for 3 years.
Nasty Sound coming from under the hood
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Sounds a lot like the fan. Either a bad bearing or bad mount. If that is what it is it’s expensive unless you do the mod described somewhere here where they install an aftermarket fan in front of the radiator.
Th at is what I am assuming it to be, which would require a 500 dollar trip or more to the Mercedes dealership.
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Dig around a bit on here and you will see a 60 dollar workaround. Involved putting in a new fan in front of the radiator instead of behind.
I saw a post on that, but I have zero know how when it comes to cars.
Cholf, I can tell you I just did the front mounted option last weekend on my 2014 Pure. I have the fan mounted flush up against the AC condenser (fan blades don't hit the condenser). It took several hours to do the job. I have to say I was hoping for better results. It's a 14" fan with sufficient CFM, but it just can't cool as efficiently as the rear mounted unit the car comes with. This option blows air through the condenser then through the radiator. I live in Texas where it's typical to have 100+ days throughout the summer and currently, this mod will not work for me. Previously my car never got above 197 degrees (I have a ScanGauge II to monitor). On a 95 degree day last week after 30 minutes of stop/go driving, then just parking in front of the house with the AC on, the temp got to 215. I just received the factory unit today and will undertake that job in the next few weeks. Smart definitely did not engineer a serviceable solution for the radiator fan. From the number of posts I've seen on the topic, this seems to be a fairly common issue.
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Dang. That’s bad news. Good luck with the repair.
Swapping the radiator fan is doable if you're even a little handy with hand tools. The part is about $150ish, and time, I'd say about 3 or 4 hours in the driveway. Totally a doable weekend project.
Basically pull the battery (important so you don't trigger the airbag warnings), pull off the front panels, pull the crash bar and gently remove the fan. It looks daunting but the front comes off in 1 big piece and opens up pretty darn nicely.
Basically pull the battery (important so you don't trigger the airbag warnings), pull off the front panels, pull the crash bar and gently remove the fan. It looks daunting but the front comes off in 1 big piece and opens up pretty darn nicely.
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What about all the issue with having to evacuate the AC system? I haven’t heard of anyone being able to do this without that issue?
I have zero tech know how, a friend of mine said to just watch youtube videos on it, so I assume it can definitely be done. The weather here never really gets above 98 F either.
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Everything I see says you have to remove the AC condenser which means evacuating the system and refilling. If ZXSQ has a way to do it without doing that I’m sure many people would love to know because I don’t think I’ve seen anyone do it yet.
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Just finished this job on my 2008 Smart Passion a couple days ago. The correct part is available through Ebay for about $75. But before you go that route consider what is involved. I also scoured Youtube for decent videos of the process without much luck. There was one that covered removing the front fender assembly fairly well. I saw, nothing on the actual fan replacement.
I finally went with this post by Jim: Noise from front end with AC on
The model fan he suggested (A Hayden fan, model 3700) was too large by a fraction of an inch on my vehicle. So I got the next model down.
Mounting the fan requires a bit of playing around. You can't really get to the other side of the radiator to use the anchor mounts that come with the fan. That's unfortunate, but you can still manage to mount it. Remember, it doesn't matter what it looks like. You wont be able to see anything of the job after it's done. It just needs to work.
You'll have to reach around the old fan to disconnect the power to it. Thread that line forward on the driver's side and splice the new fan's lines to it. At that point, fire it up and make sure you've got the fan going in the right direction. If not, just change the polarity. Also make sure the fan is spinning without hitting anything.
My car is older and I'm just hoping to get a few more years out of it. So far, it works like a charm. Very glad I didn't have to go through removing the old fan or spending a fortune.
I finally went with this post by Jim: Noise from front end with AC on
The model fan he suggested (A Hayden fan, model 3700) was too large by a fraction of an inch on my vehicle. So I got the next model down.
Mounting the fan requires a bit of playing around. You can't really get to the other side of the radiator to use the anchor mounts that come with the fan. That's unfortunate, but you can still manage to mount it. Remember, it doesn't matter what it looks like. You wont be able to see anything of the job after it's done. It just needs to work.
You'll have to reach around the old fan to disconnect the power to it. Thread that line forward on the driver's side and splice the new fan's lines to it. At that point, fire it up and make sure you've got the fan going in the right direction. If not, just change the polarity. Also make sure the fan is spinning without hitting anything.
My car is older and I'm just hoping to get a few more years out of it. So far, it works like a charm. Very glad I didn't have to go through removing the old fan or spending a fortune.
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When I did this, I got around having to disconnect the condenser by trimming off a piece of the radiator shroud.
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Ironjoey, did you by chance snap a pic of the part(s) you trimmed? I have the new fan assembly and was going to call around to local auto shops to see if they would recover/recharge my AC system before and after this job. I presume you still had to remove the radiator or no?
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That's pretty cool! If you found a way around the condenser issue that is a game changer. Would also love to see a pic of how that worked.
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I did not snap a pic, unfortunately. I disconnected the radiator and lowered it. When you line up the new shroud, there's a circular piece that the ac line goes through. I cut the circle and slid it around. Then lined everything back up. If I remember correctly, I DID disconnect the radiator hose though.
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Can I ask what year Smart you have? I have a 2014 Smart Pure. I've looked at the fan shroud 20 different ways and cannot see any possible way to wiggle the frame and radiator out without doing the full disassembly.
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