Decoder reset

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Sometimes your mobile decoders will lose their settings, often caused by a short circuit or other interruption of the track power, or mistakes 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 your decoder to its factory defaults.

The 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 only, or everyting except the speed table).

Decoder 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.

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.

Always check the manufacturer's instructions. Some decoders must be reset using Operations Mode, others will using the programming track. As mentioned above, there is no set procedure to accomplish a decoder reset.

Don't forget to cycle the track power on and off to complete the reset. This can be as easy as tilting the locomotive to raise the wheels on one side off the rail.

DCC Decoder: Default Reset Values
Manufacturer ID No. in CV8 CV to Reset plus Value
Lenz 99 CV8 =33
NCE 11 CV30 = 2
Digitrax 12 CV8 = 8
ESU (LokSound)1 15 CV8 = 8
Train Control Systems (TCS) 153 CV8 = 8 or CV30 = 2
SoundTraxx: DSDLC, DSX, Tsunami 141 CV30 = 2 CV8 = 8
QSI 113
MRC 143 CV125 = 1

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.

1 ESU recommends using the programming track.

Notes
Tsunami and QSI decoders will require a Program Track Booster or a PowerPax
MRC Decoders are not reliable for read back.

Resetting a Decoder

If you do not have control of the address use the programming track.

Start by determining the decoder manufacturer. On the programming track read CV 8.

Compare the number with the above chart for the ID (if you have a LENZ decoder CV8 will equal 99).

Write to the matching CV the value shown in the table. Writing to CV8 will not change the value contained in CV8 when you read it 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 of 3. 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.

Try the decoder on the main line using address 3. If it works, you can start your programming.

Manufacturer Specific Reset Procedures

Digitrax

Generally speaking, you 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.

ESU

LokSound V3.5

4.3 Resetting to factory pre-set values You may rest 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 LokSound Programmer 53452.

Source: Page 15 of LokSound v3.5 manual.

LokPilot

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

Source: Page 6 of LokPilot Manual.

Lenz

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 owners manual.

NCE

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 owners manual.

Addressing a Reset Decoder with the NCE Power Cab

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

QSI Decoders

Broadway, Atlas, and Lifelike often equipped their locomotives with OEM QSI (ID 113) DCC decoders.

QSI decoders have a different reset procedure. Check the manual that came with the engine.

Some use a magnetic “wand” for the reset. If there is no “wand” then open the engine or access hatch to find a reset jumper. Remove the jumper and restore the track power. There will be an audible acknowledgment from the engine 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 engine will go through its reset procedure and let you know when done.

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 engine alerts you audibly.

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

  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.


SoundTraxx

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.

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."

Source: Page 24,25 of LC SERIES DIGITAL SOUND DECODER TECHNICAL REFERENCE.

Tsunami

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 imediately 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.

Train Control Systems

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.

See Also


Some material, such as the cheat sheet and other details, taken from DCC Decoder Default Resets by Ted Freeman, Queensland Division, AR.