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OK im a little confused iv done a lot of research here on the 3 bars of death , but here is my story i was driving down my driveway ( in 1st gear ) and the engine revved up like it was in neutral , i lost power and the 3 bars came on . i did the brake, key on , go though the gears slow and got the PRND back on . Iv been driving it for 4 more days and nothing , this is my wife's smart and she is afraid to drive it ( i don't blame her ) I don't want to start throwing parts at it . A little about myself i own a Bodyshop so tearing into something im not afraid to , iv got a scanner ( Autel ) it brought up the code ( u0101 b1002 ) but im not having a lot of luck getting precise information on it .
Thanks Kenny
 

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My manual for my cheap little analyzer lists U0101 as "Lost communication with TCM. I have no listing for B1002. TCM is short for transmission control module. This thread might help a little. http://www.smartcarofamerica.com/forums/f353/transmission-tcm-question-s-114938/

The TCM is located under the drivers seat. I would check the connections and clean the contacts to see if it is losing a connection.

Also check out this link> Evilution - Smart Car Encyclopaedia

3 bars transmission problem is described here in http://www.evilution.co.uk/168


Generally the car will not start and now gears can be selected although there have been cases where the car has driven fine despite the error showing.

If the car drives fine forwards and backwards, simply disconnect the battery for 10 minutes before reconnecting. This should clear the error from the car's memory.

What Can Cause It?

The smart gearbox relies on a lot of electronics to keep it working properly, it only takes one part to misbehave to call up an error code. Causes can be one or more of the following:
•Faulty SE Drive
•Stuck gears
•Weak battery
•Faulty gear motor
•Faulty gear position sensor
•Faulty clutch actuator
•Chaffed wires

Faulty SE Drive

The gear change works on non contact hall effect sensors that are activated by a magnet
(much like a reed switch but a chip format). Gear changes should be clean, smooth and full
push or pull to the limit of the stick's travel before releasing. Hesitation during a gear change
or not pushing/pulling the stick to the full limit can cause this error code to appear.

It is unlikely that the magnet will lose its power but there have been cases where the
internal PCB of the SE Drive falls down. This can put the hall effect sensors out of reach
of the magnet causing the same problem. Usually this problem can also cause the
ignition switch to move away from the barrel making the car impossible to start. Info.

Stuck Gears

Usually related to a faulty gear motor but can get stuck in their own right.
Forcibly pushing the car back and forth usually rocks the gear box free.
If this fixes it, it may be worth thinking about a gearbox oil change. Info.
There may be a part in the gear box that isn't moving as well as
it should and a fresh batch of oil can help get things moving again.

Weak Battery

Thanks to Pedro Caria for adding this info.

It seems it is possible for the battery to be too weak to move the gear motor fully.
As the gears attempt to move and fail, the error code is bought up.
Get the battery tested and replace if it is faulty.

Faulty Gear Motor

The motor is the device that actually moves the gears in and out of position.
It is a motor that can run in both directions to select a gear through a linkage of levers and a drum. Motors can burn out, the brushes can become damaged and the connections can become faulty.

Unplugging the connector will allow you to view the connections and allow you to clean them.
Removing the torx headed bolts will allow the motor to be removed and exchanged.

Chaffed Wiring

It is worth checking the wires to the plastic connector as in many cases the protective
sheath is cut short so the internal wires are open to the elements. It has been known
for the engine movement to gradually damage the separate wires causing one or
more to ground out and therefore causing the motor to fail.

Faulty Gear Position Sensor

The sensor feeds back the position of the gears to the ECU, this allows that ECU to control
the gears via the motor mentioned above. If the sensor becomes faulty, the ECU has no
idea what gear the car is in so calls up the error to save any damage or accidents.

Sensors can become dirty as well as just break outright. Removing the two bolts located on
either side will allow you to pull the sensor from the gearbox. Unplug the wiring connector
from the sensor and pull the unit free of the car. Giving it a quick clean may help.

It is worth checking the wires to the plastic connector as in many cases the protective
sheath is cut short so the internal wires are open to the elements. It has been known
for the engine movement to gradually damage the separate wires causing one or
more to ground out and therefore causing the sensor to fail.

(The evilution info was originally posted on here by Neonspinazz)........


Hope this helps. DCO
 

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P1002

Type Powertrain - Manufacturer Controlled DTC - Manufacturer Controlled

Description
Evaporative emission (EVAP) canister purge valve - high output

Cause
Wiring short to positive, EVAP canister purge valve
 

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DME fault U0101-communication with control unit Transmission has a malfunction.

AB fault B1002-the resistance value in the ignition circuit containing driver airbag squib is too low.

AAC fault B1002-control unit heater/air conditioning operating unit is defective (interior temperature controller).

ESM fault U0101-communication with control unit Transmission has a malfunction.

Posting fault codes is of limited value without the control unit containing the code and the code description.
 
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