[kulak]

All,

I have a unique problem with my 2008 Pure Smart Car. When I park my car in my driveway the battery goes dead in 3 days.
• I have been through 2 new battery’s so it is not a bad battery.
• It has been in two shops that can find no problem, it does not go dead when they have the car, over 4 days each time?

What I have discovered is that when the car is parked in a level location the battery does not discharge? Park in my driveway with a slight upgrade and it is completely dead in 3 days. No horn or dash lights etc.

I have made no mods to the car

Any ideas as to what may be causing this problem or how to trouble shoot it would be appreciated. :shrug:

 

[jimvw57]

do you have the rain sensor on the windshield? They have been known to wear down the battery as they are always checking for rain Make sure the auto rain sense is off

 

[kulak]

No rain sensor, this car has no options, roll up windows, no alarm, no mods, just plain old pure model.

 

[smark]

Alternator, not charging.

 

[jimvw57]

I would try either parking in a different spot, or disconnect the battery and see if it still goes dead. Parking a car on a slight slope shouldn't make any difference to the electrical system. I have always parked my cars on the street with a downhill slope and never experienced them going dead even after 3 weeks time. (2008 pure, 2009 passion)

 

[Rustedwrench]

All,

I have a unique problem with my 2008 Pure Smart Car. When I park my car in my driveway the battery goes dead in 3 days.
• I have been through 2 new battery’s so it is not a bad battery.
• It has been in two shops that can find no problem, it does not go dead when they have the car, over 4 days each time?

What I have discovered is that when the car is parked in a level location the battery does not discharge? Park in my driveway with a slight upgrade and it is completely dead in 3 days. No horn or dash lights etc.

I have made no mods to the car

Any ideas as to what may be causing this problem or how to trouble shoot it would be appreciated. :shrug:

The battery draining only when parked on an incline seems implausible. The charging system would need to be tested for excessive a/c ripple on the dc output. If that tests good then a parasitic draw test would need to be done to narrow down the area of the fault. In either case the fault would have to be present for the tests to be meaningful.

Or the battery has a hole in it and the electrons are leaking out. :rofl:

 

[Mister_smart_LA]

Parasitic draw for real. I'd check for the most common issues that can cause a strong draw and quickly drain a battery. Headlamps, headlamp switch, brake lamps, anti-theft systems if applicable, suspect (although not very likely) the shift actuator, and definitely check the SAM unit while the vehicle is off. Do you have an upgraded aftermarket sound system, perhaps with amp or sub? If so, be highly suspicious about its install.

How long have you owned the car? If not original owner, dig under dash looking for an aftermarket alarm system that wasn't fully disconnected.

 

[smark]

Human error

You’ve probably done this at least once in your life – you come home from work, tired and not really thinking, and left the headlights on or didn't completely close the trunk. Overnight the battery drains, and in the morning your car won’t start. Many new cars alert you if you’ve left your lights on, but may not have alerts for other components.

Parasitic drain

Parasitic drain is due to components in your vehicle continuing to run after the key is turned off. Some parasitic drain is normal – your battery delivers enough energy to keep things, like your clock, radio presets, and security alarm operational at all times. However, if there's an electrical problem, parasitic drain can exceed what's normal and deplete the battery.

Bad charging

If your charging system isn’t working properly, your car battery can drain even while you’re driving. Many cars power their lights, radio, and other systems from the alternator, which can make the battery drain worse if there's a charging problem. Then you’ll be stranded at roadside with a stalled car that needs a boost. And even then, bad charging will drain your car’s battery. A professional mechanic will be able to diagnose what's causing a charging problem.

Defective alternator diode

A car alternator recharges the battery and powers certain electrical systems. If your alternator has a bad diode, your battery can drain. The bad diode can cause the circuit to charge even when the engine is shut off, and you end up in the morning with a car that won’t start.

Old battery

If your battery is old, it might not hold a full charge. If your car consistently won't start, it’s possible that the battery is worn out. You should generally replace your car battery every 4-5 years. If your car isn’t starting consistently, and your battery is old, battery replacement should be the first thing you consider.

Having a battery that won't hold a charge is frustrating, and figuring out what's causing the problem can be tricky. Assuming that the cause of the battery drain is not human error, you will need the assistance of a qualified mechanic who can diagnose your car's electrical problems and determine if it is the battery or something else in the electrical system.

 

[jimvw57]

All,

I have a unique problem with my 2008 Pure Smart Car. When I park my car in my driveway the battery goes dead in 3 days.
• I have been through 2 new battery’s so it is not a bad battery.
• It has been in two shops that can find no problem, it does not go dead when they have the car, over 4 days each time?

What I have discovered is that when the car is parked in a level location the battery does not discharge? Park in my driveway with a slight upgrade and it is completely dead in 3 days. No horn or dash lights etc.

I have made no mods to the car

Any ideas as to what may be causing this problem or how to trouble shoot it would be appreciated. :shrug:

The car is a Pure, no auto lights or wipers, also says no additional equipment, 2 new batteries, I find it hard to believe that it would only happen in the spot you park it at home and not sitting at repair shop for 4 days. something is different.

To start with, check the battery voltage when it is running, then after you shut it off. After a few days check it again. There has to be something being left on or running when you park it. Maybe the door locks, or the dome light from a door that is not adjusted and parking on a slope causes the light to stay on? pretty far stretch, but then so is replacing the battery twice if there was nothing wrong with them. seems like something is missing here.

 

[kheran]

I'd start looking into the ground connections at the battery and the ones near the engine. Then look at the positive connections to the starter and alternator.

 

[jwight]

Kane explains it: Evilution - Smart Car Encyclopaedia

 

[Niteshooter]

All,

I have a unique problem with my 2008 Pure Smart Car. When I park my car in my driveway the battery goes dead in 3 days.
• I have been through 2 new battery’s so it is not a bad battery.
• It has been in two shops that can find no problem, it does not go dead when they have the car, over 4 days each time?

What I have discovered is that when the car is parked in a level location the battery does not discharge? Park in my driveway with a slight upgrade and it is completely dead in 3 days. No horn or dash lights etc.

I have made no mods to the car

Any ideas as to what may be causing this problem or how to trouble shoot it would be appreciated. :shrug:

That is a very odd issue, ok so no mods and does not discharge when parked level.

This makes me suspect a couple of things, the first being a switch such as the door switch being triggered when the car is on an incline. I know that if one of our interior lights is left on it usually takes a couple of days to drain the battery fully. Perhaps spray some WD-40 into the door switches and see what happens.

The second is that somehow the battery is shifting in it's tray enough to cause it to short, granted if it was a direct short on the battery there would be a much faster drain and likely tell tale signs of an electrical short such as a burning smell.

Not sure where you are located but if it's somewhere that is using salt or other type of ice melter perhaps you are having a problem with an electrical connector that when tipped just enough is shorting out I hope this is not the case as this would likely be a nightmare to diagnose.

Really long shot idea, is it possible that somehow the brake pedal is loose on it's mount and somehow tripping your brake lights on an incline. Hmmm does this happen when the car is pointing a certain direction, e.g. nose first or tail first? Is one or the other try reversing the position, granted that might be of little help in actually determining the issue but I'm curious....

 

[casestang2001]

What did you find was wrong with your car? I have a 2008 passion that I've owned for a little less then a year now and it has the same exact problem.

 

[Gearhead]

Yup... Same issues, 2009 and 2014 (the last year of the 451). Some of the CPUs on the Smart are always on. Perhaps some code having to do with the hill-holder feature are eating current (this holds the brakes on an upfacing hill until the car starts moving forward). Easy trick to try, just back up the driveway instead with the car facing downhill...

 

[ccc99]

Smart Car Battery Drain

I have narrowed the issue down to Fuse#12 which connects to:
Instrument cluster
Additional instruments
Microwave sensor
Rain sensor / light sensor
Alarm siren with inclination sensor
Left turn signal lamps/brake light relay
Right turn signal lamps/brake light relay
Mirror heater relay
Automated manual transmission control unit
TPM [RDK] control unit
Combination switch
Cockpit switch group
Data link connector
Starter-alternator control unit
STH radio remote control receiver (engine 780.009)
Rear fog light relay
Any advice on which one is most likely the culprit draining the battery?

 

[1983JZR3W]

If I remember correctly, a few years ago, some people were having battery issues from the rain/light sensor. I don't have that feature, but someone will chime in soon that can help you.

 

[Prrtheads2]

Ok on the same type of thread ..
I get the battery light on my dash when I start the car. Stays on until I get over 2500 rpm then goes off BUT if I don't drive for a few days ... dead battery. Would this be the same diode issue?? Sorry to jump into a stream but new to the forum and don't know how to start a new thread ....but figured it was simular! Thx