[HiBeamsOn]

Within a relatively short amount of time my 2008 Passion Cabrio has experienced the AC blowing totally warm, the alarm system consistently triggering unless I use the tow button on the dash, decreasing fuel economy which was consistently 36-43 now down to 20 mpg, and heavy electric steering where sometimes it flutters rapidly between being light and heavy while turning a city corner creating very jerky and unstable-feeling turns. Could any of these be related from a central controller failing, or is my smart just rapidly falling apart? I have 63,000 miles on the car, and all of these issues began around the 61,000 mark.

 

[rbrtryn]

All this sounds like your charging system is failing. Perhaps not putting out enough current to run the engine plus all of the other electrical stuff in the car.

Your local parts store should have equipment to test this for you.

Other ideas:

• Corrosion on battery terminals or ground points, causing arcing
• One of the wiring looms has worn through, causing a short.
• Water ingress into the SAM or ECU.

 

[smark]

Add some freon to you AC unit. What’s a tow button? Are you towing something, to get only 20 mpg? When was the last time you changed your spark plugs? Engine air filter. Ran fuel injectors cleaner though your cars fuel System. Have you checked your tire pressure? Is it correct on all for tires. When did you align you tires, the last time?

Sounds like all your issues are unrelated ones.

 

[HiBeamsOn]

The tow button is the button on the dash that you press to disable the alarm’s motion sensor if you need to have your vehicle towed or, in my case, because the alarm goes off for no apparent reason. I don’t tow anything, I changed my plugs and air filter in November, tire pressures are to spec, and I check them each month.

 

[smark]

The tow button is the button on the dash that you press to disable the alarm’s motion sensor if you need to have your vehicle towed or, in my case, because the alarm goes off for no apparent reason. I don’t tow anything, I changed my plugs and air filter in November, tire pressures are to spec, and I check them each month.

That is a after market, feature for Being towed I guess. Why don’t you have that thing, disconnected. if your never use it.

 

[HiBeamsOn]

That is a after market, feature for Being towed I guess. Why don’t you have that thing, disconnected. if your never use it.

The alarm system was a factory option, and the feature I’m talking about is a part of that system. No part of the alarm system is an aftermarket product.

 

[jimvw57]

Tow button is a stock item, there were lots of issues with the sensor for the alarm and may were replaced under warranty (which sadly you are past) If you have not added refrigerant up to now, you are probably low. charge ports are on the pass side front and can be difficult to get to. as for MPG, you may have gotten some bad gas. another possibility is that some critter has been making a meal of your wiring system.

 

[HiBeamsOn]

I never thought of the critter possibility!

 

[dhlairbusb4]

Get your battery tested, any auto parts, walmart etc... will to this for free.
If that tests good, then most likely the alternator is OK... but this all sounds electrical to me.

 

[Goggles Paesano]

Drop in mpg check oxygen sensor(s). That is why it is a good idea to track mpg at each fillup. You can see if something is starting to fail. Most likely you are running lean but might not be enough to throw a code. Check for codes first.