Multifunction Decoder Reset

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Summary: Sometimes Multifunction Decoders lose their settings, or mistakes were made when configuring a new decoder. Rather than return the decoder to the dealer or manufacturer thinking it is defective, a simple reset will restore a decoder to its factory defaults.

Multifunction Decoder Reset

A decoder reset forces all the CV values back to the initial factory settings. This is useful if your decoder becomes unusable or if you want to have a fresh start with the decoder. Not all decoders have CV reset functions, please refer to your owner's manual for full instructions and details on it's use. Some decoders allow you to reset everything, or only certain sections of the decoder, such as the speed table or everything except the speed table.

The reset is entirely handled by the decoder. This function is non-intrusive, that is, you don't have to use this feature at all. The only necessary tools to activate this function is a method in which you can program various CVs. This can be handled by the throttle of most systems, or through the use of DCC software.

The reset procedure is not part of the NMRA's Digital Command Control Standards or Recommended Practices (RPs), so there is no default method to reset a decoder. Also, see below for a note on the Default Address.

Decoder Factory Reset

Main article: Service_Mode_Programming#Decoder_Factory_Reset

NMRA standard S-9.2.3 defines a factory reset packet. It also recognizes that alternative methods exist, but requires this method to be supported as well.

Cheat Sheet

The following table has general notes on resetting a decoder. Read the specific text below for any additional information which may apply.

If you don't know the address, use a programming track to accomplish a reset.

It is only possible to read CVs on a programming track in Service Mode.

Example: A DCC system's command station which utilises a single two wire track output can switch between normal and Service Modes as required. When in Service Mode changes will be applied to every locomotive on the track which is connected to that output. Other command stations may have a dedicated and labelled programming track output for this specific purpose.

Always check the manufacturer's instructions. Not all manufacturers use the same CV for the same purpose. Some decoders must be reset using Operations Mode, others will be using the programming track. A jumper inside the locomotive may need to be installed or removed, or the position of a switch changed.

As mentioned above, there is no set procedure to accomplish a decoder reset.


  1. A Manufacturer ID equalling 255 or multiple readings of 255 when reading other CVs is an error message.
    1. The Manufacturer ID (CV8) is for the locomotive's decoder, not the system used for programming. The Manufacturer ID is held by CV8.
  2. Cannot Read CV is also an error message.
    1. Error messages indicate the DCC system did not get a response back from the decoder. Check connections and clean track as necessary. Try another locomotive for comparison.
  3. When attempting to read CVs of a sound equipped multifunction decoder use a programming track booster if needed. Do not use a DCC Specialties "PowerPax"!
    1. Do not connect any type of programming booster to an NCE Power Cab.
  4. Do not interrupt the process.
    1. Some multifunction decoders can require a lot of time to complete the programming sequence. Interrupting it can result in an unresponsive decoder
  5. It is always a good idea reboot / power cycle the system and the decoder after a factory reset. Some decoders may not be completely reset until the power is removed and restored. Similar to rebooting a PC after it is updated.
  6. To learn more about configuration variables see the related DCCWiki Page: Configuration Variables.

Typical Reset Values

Don't forget to cycle the track power to complete the reset process. A DCC system maintains power on the track at all times. Cycling the power can be as easy as tilting the vehicle to raise the wheels on one side off the rail and waiting a few seconds. The reset process may require several power cycles to complete.[1] [2] Multifunction Decoder Default Reset Values
Decoder Reset Cheat Sheet
Manufacturer Manufacturer
ID No. in CV8[3]
CV to Write
plus Value
Lenz Elektronic [4] 99 CV8 = 33
NCE Corporation 11 CV30 = 2
Digitrax[5] 129 CV8 = 8 or 08[6]
ESU (LokSound)[7] 151 CV8 = 8
Train Control Systems (TCS) [8][9][10] 153 CV8 = 8 or CV30 = 2
SoundTraxx: DSDLC, DSX, Tsunami[[11][12][13] 141 CV30 = 2 CV8 = 8
QS Industries[13] 113 See text below. Refer to the manual for additional details.
Model Rectifier Corp (MRC)[14] 143 CV125 = 1
Broadway Limited Imports (BLI) [13][15] 38 CV8 = 8
Bachmann Trains [16] 101 CV8 = 8
MTH 27 CV8 = 8
DCC Concepts 36 CV8 = 2 or 8
Kato Precision Industries 40 CV8 = 8
Hornby Hobbies Ltd 48 CV8 = 1
Gaugemaster 65 CV8 = 8
Atlas Model Railroad Products 127 CV8 = 99
ZTC 132 CV8 = 8
Zimo Elektronic 145 CV8 = 8
LGB 159 CV55 = 55
Arnold / Rivarossi 173 CV8 = 8

Resetting a Multifunction Decoder

If one does not have control of the address use the programming track.
  1. Start by determining the decoder manufacturer.
  2. On the programming track read CV 8.
  3. Compare the number with the above chart for the ID
    1. A LENZ decoder's CV8 will equal 99
  4. Write to the matching CV the value shown in the table. Writing to CV8 will not change the value contained in CV8 when read back. When resetting the decoder, it may respond by flashing the lights or sounding the horn. Resetting a decoder will change the address back to the default. Cycle track power on and off to complete the reset. Read the instructions for the decoder to verify what should happen after a reset (headlights flashing, etc.) to determine if the process was successful.

Use caution when programming in Operations Mode.

Address Defaults

Important: The NMRA Standards specify that the default Primary Address (CV1) for a retail multifunction decoder is 3. A factory installed multifunction decoder is exempted from this requirement by the Standard, verify with the instructions for the locomotive as to the default address. [17]

Manufacturer Specific Reset Procedures

Due to the increasing complexity of multifunction decoders, a complete reset may not be possible within the time limits specified by the DCC Standard. Some decoders offer the ability to reset portions of their configurations.


Generally speaking, one can reset Digitrax decoders by writing a value into CV08 as follows:

Decoder reset lets you reset all CV values to the initial factory settings. To reset all CV values, program CV08 to a value of 008/x08. You also have the option of resetting all values except the 28 speed step tables. To do this, program CV08 to a value of 009/x09.

Source: Digitrax website

Normally this will work with all Digitrax decoders except those noted below.

Specific Digitrax decoder notes

Add notes/comments for different proceedures for Digitrax decoders which the above doesn't apply.

  • None at this time
Video Tutorials
Resetting a Decoder with the DCS50/DCS51

Resetting Decoder with a DB150 and DT402 throttle

Resetting a Decoder with DCS100/DCS200 and a DT402


LokSound decoders do not require a program track booster. Interrupt power for 5 seconds to complete the reset cycle.

ESU does not recommend Programming on the Main (Operations Mode), use Service Mode on a programming track, with Direct Mode if possible.

  • JMRI has a Reset menu available for previous roster entries for LokSound equipped locomotives.
  • The LokProgrammer also has a Reset facility.
LokSound V5 DCC
  • Write the value 08 to CV8. [18]
  • Using the LokProgrammer: Under Programmer menu, select Reset decoder and follow the onscreen instructions.
LokSound V3.5

4.3 Resetting to factory pre-set values: You may reset the decoder settings to the factory pre-set values at any time. Write value 08 in CV 08. A reset of the sound files is only possible with the aid of the LokProgrammer 53452.

Source: Page 15 of LokSound v3.5 manual.


You can easily reset the decoder by writing the value 08 in CV 08 at any time.

Source: Page 6 of LokPilot Manual.


The LokProgrammer can quickly and thoroughly reset an ESU decoder. Use the Reset Decoder function and follow the prompts. (LokSound V5 manual, p92)


Current versions of JMRI deliberately deactivate the Reset to Default button for ESU multifunction decoders.

Prior to attempting to reset an ESU decoder, use the New Loco > Read Type from Decoder to identify an ESU decoder. Modern ESU multifunction decoders have unique identification parameters. Blindly attempting to reset the decoder model will only create new problems. Create a new roster entry, and do the reset from the menu there.

See Programming ESU Decoders for a more complete explanation of JMRI and ESU decoder interactions.


For a non-responsive MTH locomotive:

  1. Place the locomotive on the main track (Operations Mode Programming will be used)
  2. Select Address 55
  3. Enter Operations Mode programming (See your manual if necessary)
  4. Select CV 55 on the throttle, set its value to 55
  5. Write this value to the decoder

The locomotive should respond to address 3 when successful. The decoder can now be programmed using Ops Mode.

Some MTH locomotives have a small battery onboard to maintain decoder settings. If the locomotive has not been used for a period of time, decoder settings will be lost.


CV8 Register-8 Manufacturers Identification: Contains the manufacturer ID of the decoder, (Lenz =99). Writing a value of 33 using Register mode resets all CVs to their factory condition.

Source: Page 7 of LE1835 manual.

Other models are similar, refer to owner's manual.

Tilt locomotive to one side to disconnect from track power, wait 7 seconds to reset decoder.


SR Series

CV30: Set this CV to 2 on the programming track and the decoder will reset to factory settings.

Source: Page 8 of D13SRJ ver 3.5 decoder manual.

Other models are similar, refer to owner's manual. Reboot the NCE DCC system after performing this procedure.

Addressing a Reset Decoder

Power Cab: After reset to factory default, select 3, not 0003. The system sees 0003 or 003 as a long address.

Resetting NCE Decoders to Factory Settings
Recovery Mode for NCE Decoders

NCE has a feature in their DCC system software which allows for a recovery mode.

This works with an NCE DCC system and NCE decoders only.

Program track mode / Recovery mode is not available in the SB3, SB3a and SB5.

NCE does not recommend using Recovery Mode with other manufacturer's decoders, as you may get unintended results. Not every decoder uses the same CVs for the same purposes.

How to enter Recovery mode on NCE Powercab
Physical Register Mode
Main article: Decoder Reset/Physical Register Mode

This mode allows you to program a decoder no matter what state it is in. You do not even need to know the address (hence the danger of programming all your decoders at once). It will also work if the decoder's memory has become corrupted.

Note the statement warning of the possibility of programming all your decoders at once.

Since there are a number of options, and the process varies depending on the command station, please read the Recovery Mode For "Dead" NCE Decoders webpage on the NCE website.

Once the process is complete, the entire DCC system must be rebooted, with the target locomotive still on the track. If successful, it should respond to address 3.

QSI Decoders

Broadway, Atlas, and Life-Like/Proto-2000 often equipped their locomotives with OEM QSI (ID 113) decoders.

QSI decoders have a different reset procedure. Check the manual that came with the locomotive. Some may use Indexed CVs for specific reset procedures.

A programming track booster is required. Do not use the DCC Specialties PowerPAX. For OPS Mode disable voice playback, CV62 = 0 to disable.

Some use a magnetic “wand” for the reset. If there is no “wand” then open the locomotive or an access hatch to find a reset jumper. Refer to the user manual for details.[19] Remove the jumper and restore the track power. There will be an audible acknowledgment at the end of the reset process. The whistle/horn is often sounded three times.

Replace the jumper and test out using address 3.

If a “wand” is used, locate the internal reed switch and place the “wand” over it for a moment. When track power is restored, the decoder will go through its reset procedure and let you know when done. The reed switch may fail at some point, causing the decoder to be stuck in reset mode. The reed switch can be removed without incurring any new issues.

To locate the internal reset (reed) switch, place the engine on active track. Slowly move the “wand” over the top of the body or tender until the decoder alerts you audibly.

This video shows three different hardware reset methods for a Quantum Sound Equipped Broadway Limited Imports locomotive.

QSI also has a user software reset using the following multi step procedure:

Review the manual for the decoder as there may be additional options.

  1. Place engine on main track if it is still responding to its address. If not responding you may need to use the program track.
  2. Set CV49 to 128
  3. Set CV50 to 255
  4. Set CV56 to 113

As the decoder in the engine resets, you will hear an audible response, the horn may sound three times, or it may talk to you.

Test the locomotive using address 3.

You can then go ahead and set the loco number as you desire and/or reprogram other CV’s.

An irritating issue with QSI decoders is when they do get corrupted by a short, the locomotive can exhibit very erratic operation. Resetting it back to default will put you back in control of its performance.

If the address is known:

  1. Using Ops Mode, enter CV62 = x, where x is the number of the CV whose contents you want to read
  2. The decoder will verbally respond with the content of CV x

BLI Paragon 2

This video demonstrates a hardware reset of the Paragon2 decoder.


Also see the video: Soundtrax CV Reset

  • Tip: Soundtraxx suggests using the CV reset to test the lighting functions and configuration in a newly installed multifunction decoder: The lights should flash 16 times after the reset to confirm it worked. If a light does not flash, there is a wiring error. If it does flash, the CV which controls that function may be the issue.
DSD-150 / DSX

To reset all the CV values to the defaults can be... done by programming CV 30 with 02 in service mode and turning power to the DSD off and back on. Note: This bit can be programmed only in service mode. Writing any data value during operations mode will clear all error bits to 0. [20]

Source: Page 23 of Digital Sound Decoder Technical Reference part 2.

LC Series

Resetting all the CV values to the defaults can be... done by programming CV 30 with 02 in service or operations mode and turning power to the DSD off and back on."



Resetting the CVs... can be quickly reset to their factory default values using the following procedure:

  1. Program CV 30 to 2 (or CV 8 to 8) using either Service Mode or Operations Mode
  2. Place locomotive on a powered section of track. If locomotive is already on the mainline, cycle power to the decoder by turning power to the track off and then back on.
  3. After power is restored to the track there should be no indication of activity other than the power LED turning on for a period of six seconds. If sound comes on immediately upon restoring power, the decoder did not reset. Repeat steps 1 and 2.
  4. Once the six-second period has elapsed, the sound should come on and the headlight, backup light and onboard diagnostic light will blink 16 times indicating that the CVs were successfully reset.
  5. Tsunami should now respond to short address 3 just as it did when it was first unpacked.
  6. If you cannot get the decoder to reset, check to see that it has not been inadvertently locked (see “If You Forget the Lock Code” in the previous section).

Source: Page 12 of Tsunami Steam Sound User’s Guide.


To reset an Econami Decoder, there are options.

Writing the following values to CV8 will do a reset (a value of 8 is needed) or only reset groups of CVs.

  • 8 = Full CV reset
  • 9 = Reset CVs 1-128
  • 10 = Reset CVs 129-256
  • 11 = Reset CVs 1.257-1.512
  • 12 = Reset CVs 2.257-2.512

Source: Econami Manual

Train Control Systems

For a full list of reset options see their webpage at Support - Resets.

A value of 2, 8, 10, 11 or 12 can be written to CV 8 to cause a reset to occur. These values depend on the type and version of TCS multifunction decoder. Additional options are availalbe for their WowSound multifunction decoders.

A Nuclear Reset is also available for their WoWSound series. This requires writing spcified values to CVs 201 – 204. See their support page for full details.

Factory Reset in Operations Mode

It is possible to perform a factory reset while in Operations Mode.

Write one of the following values to CV8:

  • 2
  • 8

After writing one of the two values above turn off track power, then restore track power to complete the reset. Using Ops Mode ensures that power is always available and the reset process will successfully complete.

Using Ops Mode requires that the decoder's address is known. If an address is not specified, every decoder on the layout may be reset. Either use an isolated section of track, or remove all decoder equipped vehicles from the layout to avoid unintended consequences when using Ops Mode to perform a reset.

X Series

Factory Reset Sets all CVs with a shaded value back to that value. As soon as you enter a 2 in either CV 8 or CV 30, The reset is complete.

Source: Page 1 of Advanced X series Features.

Note: Some earlier non-X series decoders also supported reset as specified above.

Decoder Reset Packet for All Decoders

A special packet, called the Decoder Reset Packet, which consists of three bytes, each having a value of zero (0). When the decoder receives such a packet, it will immediately erase all volatile memory, including speed and direction data, and return the decoder to its normal power up state. If the locomotive is at a non-zero speed, it shall come to an immediate stop.

The command station is prohibited from sending packets with addresses from 100 to 127 for a period of 20mS following the reset packet, unless the intention is to enter service mode.

This process does not alter any stored CV values, it is used to prepare the decoder for programming.

See Also

Some material, such as the cheat sheet and other details, taken from DCC Decoder Default Resets by Ted Freeman, Queensland Division, AR, and Resetting DCC Decoders, by Ron Gager of the British Region NMRA.


No Warranties Express or Implied. The decoder reset process is not part of the NMRA DCC Standard. While every effort has been made to present accurate information, reset processes described may be changed at any time by the decoder's manufacturer. A reset may also cause loss of data or sound files.

While it may be possible to overwrite default settings in the decoder firmware, unless done properly any custom variables will be lost. This usually requires proprietary hardware and software. Your dealer may be able to provide this service.

Software such as DecoderPro is useful to restore decoder parameters after a reset, but the contents of the decoder must have been read and stored on your computer prior to any event requiring a reset.



  1. Power cycling the DCC system may be required.
  2. The time available in programming mode may not be long enough for the reset process to complete. See Service_Mode_Programming#Decoder_Factory_Reset for more details.
  3. CV8 is the Manufacturer ID. This value is assigned by the NMRA. Writing any value to CV8 does not change its contents as it is a read-only variable.
  4. Some Lenz decoders may work with a value of 8 or 33 in CV8. Older decoders used 33.
  5. See Decoder_Reset#Digitrax for additional details.
  6. If writing a value of 8 does not work, try writing 08.
  7. ESU recommends using the programming track.
  8. A programming track booster may be required if using Service mode.
  9. Operations Mode is preferrable if possible.
  10. For more options see their wiki page: Support - Resets
  11. Programming track booster may be required required.
  12. Newer Soundtraxx Tsunamis may not require the program track booster
  13. 13.0 13.1 13.2 Soundtraxx (Tsunami) and QSI decoders will require a PTB-100 Program Track Booster. Do not use a PowerPax.
  14. MRC Decoders are not reliable for read back
  15. Refer to documentation for vehicle as BLI also uses proprietary multifunction decoders in their manufactures.
  16. Bachman products may be equipped with Soundtraxx decoders
  17. S-9.2.2: The default value for this Configuration Variable is 3, if the decoder is not installed in a locomotive or other unit when shipped from the manufacturer.
  18. LokSound_5_ESUKG_EN_InstructionManual_Edition-5_eBook.pdf. ESU does update manuals for current products regularly.
  19. Some decoders may use a switch in place of the jumper.
  20. Page 23 of Digital Sound Decoder Technical Reference part 2.