Knowledge base: Decoder

We test all decoders automatically, with a test bench and a dedicated software made by us. This software was improved over the years, and it is used to validate each decoders hardware before it gets the latest firmware and is shipped. All the decoders has to pass this test, and as a result they are validated. Later, before delivery, if it is the case, the decoders are updated with the latest released firmware. At that time, the basic functionality is tested again. Which means, only tested and working decoders leave our factory. If your decoder is not working anymore, some of the information below might help you solve the problem.


If you would like to know more about what we do to make sure only 100% working decoders are being shipped to our customers, read all about our test process here.


• Decoder damage protection

A: Under normal circumstances, there is no reason for the decoder to  be damaged, it has quite high current capability, and internal protection (on the motor outputs and AUX outputs too). In case of a short circuit, the decoder goes in a protection state, and disables the motor/AUX outputs. At the next start-up, first the short circuit are verified, if it does not appear anymore, the decoder will start a normal operation. If you can read out CV30, this gives information about the cause of the short circuit. Unfortunately, if you can't read out anymore the decoder, it is not possible to identify the cause.


• Train with decoder installed doesn’t respond

A: Test decoder outside of train. Directly to DCC steering unit or with a decoder tester like ESU Profi-Prüfstand. If it can be read, but doesn’t work as it should, enter value 8 in CV 8 to reset the decoder.


• Use track input instead of blue (+) wire to connect light

A: You can connect each light using the white (front) and yellow (rear) wires as a minus (-) and one of the track connections as the + connection. Make sure both + cables leading from the lights will go to same track connection.


• Using traditional light bulbs vs LED’s

A: f you are using old type light bulbs, they have a very low resistance in cold state, which could trigger the current  protection of the outputs. In this case we recommend to connect a series resistance (value of 22-33 Ohm )  with the light bulbs. If you are using LEDs, it will be not the case, but for LEDs a current limiting resistor should be present (this is present if the locomotive has LED lights from the factory). Between the power outputs (white/yellow wire) and track there will be almost the full track voltage.


• Only one LED is on after pressing function key, even when CV value is set to show both

If you  have two LEDs each connected to a function output (for example OUT 1 and OUT 2) and you set the CV value of a function key to have them both turn on when pushing the button (fx value 3 for OUT 1 and OUT 2), but only one light is on, you might have both LED’s share one resistor. Normally its better to use separate resistors for each LED. If the two LEDs are not the same type may have different voltage drop, 


• Setting light intensity of front light

A: If you like to change the intensity of a light source, which is linked to  one of the AUX functions, this can be set with a value from 0-255 in CV 48 to 57 inclusive.


• Which decoder template to use in JMRI DecoderPro

A: For both Lokommander Micro and Mini there are default settings under: Create New Loco> Decoder installed> Tehnologistic (Train-O-Matic). If you don’t see it, update to the latest version of JMRI.


• Front lights stay on, even when they are not activated

You probably have caused a short when fitting the decoder. Check CV 30 for an error report. Try resetting decoder: value 8 in CV 8.


• How to set long addresses in 3 steps

 Step 1 - You have to set the long address in CV17 and CV18 first. According to our tOm cvTool (a little helper), the long address of for example 1015 requires CV17 = 195 and CV18 = 247 (see image 1). The decoder will still react at this moment to its short address (3), since we have to configure it, that the long address will be used.

Step 2 - In CV29 (the main configuration CV), you will find the default value 14 (normal function mode enabled, DC and DCC mode enabled, and RailCom enabled) (see image 2). You have to set the so called bit 5, which will tell the decoder that his long address will be used. This can be done by writing the value 46 to CV29 (see image 003).

Step 3 - There is no step 3. At this moment, your decoder will react to all DCC commands transmitted to the long address 1015.

Image 1

Image 2

Image 3

• CV value can’t be read.

Your digital control station might be too old. It requires RailCom implementation on the control station side.


With the throttle fully open, train doesn’t drive at full speed, but only very slow.

By default, F3 is set to enable shunting mode, but it will also enable AUX3. So if you have for example interior lights connected to AUX3, then you will also enable shunting mode. You can change the F key for the shunting mode by allocating another F key in CV 114. 0 will disable the shunting key completely (no F key assigned).


Slow start and stop is not working, even though a higher value is set in CV3 and CV4.

Probably function key F4 is active. By default, F4 is set to disable acceleration and deceleration, but also to activate AUX4. You can change the F key for the acceleration/deceleration mode by allocating another F key in CV 115. 0 will disable it completely (no F key assigned).


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