ESU Decoder Tips, Tricks, and other Useful Information


Listed below are answers to some of the most common questions that have come our way. Hopefully your question will be answered in this list, if not please give us a call.

Not sure what decoder is installed in your locomotive? Place the locomotive on the program track (LokSound decoders do not require a program track booster) and read back CV 8 (not 08). If your system gives you back a value of 151 your locomotive has an ESU decoder. If your system gives you back an error that it cannot read the decoder or you get a value of 141 your locomotive has a SoundTraxx decoder. SoundTraxx decoders require a program track booster for most DCC systems. If you have a SoundTraxx decoder, please look at our SoundTraxx Decoder Tips and Tricks page.

When selecting any locomotive for the first time out of the box, the address is 3 with no leading zeros. Do not type 03.

Decoder reset is CV 8 to 8 (again no leading zeros) Do not type 08. This can be done on the program track or the main track. Always use Direct mode programming if you have a choice. If done on the main track, interrupt track power for 5 seconds and restore. The decoder address should now be 3. If the reset does not work on the main track try it on the program track.

Having trouble programming CVs 255 to 511? Please Click Here

Looking for the full list of HO & N scale Cab Forward Sound Volume CVs? Please Click Here

Mapping Run 8 and Coast in the N scale SD40-2

NOTE: Starting with item #49355 as of December 2015, the rotary beacon is functional on all SD40-2 models that come with the rotary beacon part on the roof. The rotary beacon is activated with Function 6 on your DCC system.

Locomotive(s) CV Number = CV Value Description
All Locos
Decoder Reset
CV 8 = 8 Resets the locomotive to factory defaults. Remove the locomotive from track power after the reset, wait 5 seconds, then restore track power to the locomotive. Note the locomotive address will be 3.
All Locos
DCC Addressing Info
CV 1 = Short Address (Default = 3)
CV 17, CV 18, CV 29 = Long Address
CV 1 stores all addresses from 1 to 127 with no leading zeros! These are considered "short" or "2-digit" addresses. CV 17 and CV 18 store all addresses from 128 to 9999 (Digitrax systems limited to 9983). These are considered "Long", "Extended", or "4-digit" addresses. CV 29 bit 5 (value of 32) has to be turned on in order to enable an address from 128-9999.
NCE systems can control addresses 1-127 as "Long" addresses, however you must type the leading "0" before typing the address. You'll get an asterisk symbol in front of the address to signify that you are controling a "Long" address between 1-127.
See our Extended Address Table for more information.
All Locos
Reduce Motor Hum
Disable Start-Up Delay
CV 124 = 0 Reduces most of the motor hum. This setting will disable the movement delay while the locomotive is "starting up". Some motor hum may still be present due to the Back EMF. The only way to stop the motor hum completely is to turn the Back EMF off which we do not recommend.
All Locos
Reduce Motor Hum
Enable Start-Up Delay (Default)
CV 124 = 4 Reduces most of the motor hum. This setting will enable the movement delay while the locmotive is "starting up". Some motor hum may still be present due to the Back EMF. The only way to stop the motor hum completely is to turn the Back EMF off which we do not recommend.
All Locos
Momentum Settings
CV 3 - Acceleration Rate = Varies
CV 4 - Deceleration Rate = Varies
CV 3 sets the amount of Acceleration delay as the locomotive is throttled up. CV 4 sets the amount of Deceleration delay as the locomotive is throttled down. The range for both is 0-255.

InterMountain Defaults:
Cab Forward: CV 3 = 40 / CV 4 = 30
All F units: CV 3 = 40 / CV 4 = 56
ES44AC / ES44DC: CV 3 = 60 / CV 4 = 40
SD40-2: CV 3 = 40 / CV 4 = 56
U18B: CV 3 = 40 / CV 4 = 56
All Sound Locos
Basic Speed Control
CV 2 (VStart) = 2 (Default)
CV 6 (VMid) = 88 (Default)
CV 5 (VMax)= 255 (Default)
The value of CV 2 controls the speed at speed step 1 of 28. The value of CV 6 controls the speed at speed step 14 of 28. The value of CV 5 controls the speed at speed step 28 of 28. The decoder interpolates the values of steps 2-13 and 15-27 based on the value of CV 6.
The ESU LokSound Select manual incorectly identifies the range for CV 6 and CV 5 as 0-64 with a default value of 64. The actual range is 1-255 for all three CVs.
Non-Sound Locos with LokPilot Standard V1.0
Basic Speed Control
CV 2 (VStart) = 2 (Default)
CV 6 (VMid) = 22 (Default)
CV 5 (VMax)= 64 (Default)
The value of CV 2 controls the speed at speed step 1 of 28. The value of CV 6 controls the speed at speed step 14 of 28. The value of CV 5 controls the speed at speed step 28 of 28. The decoder interpolates the values of steps 2-13 and 15-27 based on the value of CV 6.
The range is 1-64 for all three CVs.
All Locos
Full Speed Curve
CV 67-94 = Varies ESU does not use CV 67 (Speed step 1) nor CV 94 (Speed step 28). Speed step 1 is controlled by CV 2 and speed step 28 is controlled by CV 5. The speed curve is then controlled by CV 68-93 (speed steps 2-27). Enable the speed curve by adding a value of 16 to the current value in CV 29. If you do not know the current value of CV 29 you can read CV 29 using the program track. If you use an extended (4-digit) decoder address of 128 or higher, activate the speed curve by setting CV 29 = 62. If you use a short (2-digit) decoder address of 127 or lower, activate the speed curve by setting CV 29 = 30.

NOTES:
(1)Set CV 3 (Acceleration Rate) and CV 4 (Deceleration Rate) to 1 in all locomotives before starting to set the speed curve.
(2)Be sure to put your DCC system's throttle in 28 speed step mode before attempting to change the speed curve. You can go back to operating in 128 speed step mode if you prefer once the speed curve has been set.
All Locos
Forward & Reverse Trim
CV 66 - Forward Trim = 128 (Default)
CV 95 - Reverse Trim = 128 (Default)
These CVs multiply all data points in the speed table (either CV 67 to 94 or CV 2, 5, 6) by a factor of n/128 (where n is the value in CV 66 or CV 95). This results in the overall speed curve to be adjusted up or down without the need to adjust the speed table points again. CV 66 and 95 can hold values between 0 and 255. A trim value greater than 128 will result in a higher speed, a trim value less than 128 will result in a lower speed. A value of 128 maintains the original scaling factor of 1 and will therefore have no influence in the speed curve. Using different values for the forward and the reverse trim will result in different speed for forward and reverse. This can be useful for speed matching a locomotive in a specific direction.
All Locos
Smoother Motor Control -
Option 1
CV 54 = 0
This is an ESU Automatic Motor Control Adjustment that checks for binding in the drive. Set CV 54 to 0. Place loco on the main powered track (if not there already). Have at least 2 feet of straight track in front of the locomotive and press function 1 (the bell function). The locomotive will run at a very high rate of speed and then slow to a stop with it's bell on. Turn the bell off and then test the locomotive for smoother motor control. If this doesn't work to your satisfaction you can repeat the process or try Option 2 below.
All Locos
Smoother Motor Control -
Option 2
CV 52 = 127
CV 53 = 160
CV 54 = 127
CV 55 = 127
Set these CVs if your locomotive pulses or jerks as it runs. (Try Option 1 above first!)
All Diesel Locos
Non-Directional Headlight
CV 32 = 2 FIRST
CV 282 = 3
Non-Directional Front Headlight - This should make the forward headlight to remain on in reverse while turning on the reverse light.
If you do not want the reverse light on in reverse, set CV 282 to 1 instead of 3.
Cab Forward
Chuff Rate - Setting 1
CV 57 = 96 (3.07 seconds) (Default) Setting for the distance of steam chuffs at speed step 1. The range is 0-255.
Cab Forward
Chuff Rate - Setting 2
CV 58 = 61 (Default) Adjustment for the distance of steam chuffs at higher speed steps. The range is 0-255.

The chuff rate is affected by changes to the momentum settings and/or changes to the speed tables. Setting the chuff rate will require trial and error to get the desired values.
Cab Forward
Random Sounds
Min Distance CV 61 = 10 seconds (Default)
Max Distance CV 62 = 15 seconds (Default)
Adjustment for the distance of Random Sounds. This sets the range of time required for Random Sounds to play. CV 61 controls the minimum amount of time that must pass before the Random Sounds can play and CV 62 controls the maximum amount of time before the Random Sounds must play. The default settings indicate that the random sounds will play between 10 seconds and 15 seconds. After the sounds stop, the timer resets. CV 61 cannot be set higher than CV 62 (CV 61 will match CV 62) and CV 62 cannot be set lower than CV 61 (CV 62 will match CV 61). The range for both of these CVs is 0-255 (0 seconds to 255 seconds).
ES44AC / ES44DC ONLY
Add E-bell to Air Horn
CV 32 = 2 FIRST
CV 319 = 1
Adds auto E-bell sound to activate with the air horn. (As per Prototype).
ES44AC / ES44DC ONLY
Auto E-bell Volume
CV 32 = 1 FIRST
CV 323 = 0 (Default)
Increase or Decrease Auto E-bell volume. Range is 0 (off) to 128 (max).

The easiest way to turn OFF the Auto E-bell activating with the air horn is to set the E-bell volume to 0 as described above.
ES44AC / ES44DC ONLY
Change E-bell to Air Bell
CV 48 = Current Value +64 Add 64 to current value of CV 48 and interrupt track power for at least 1 second. Changes E-Bell sound to Air Bell sound for early delivered GEVOs. (Default CV 48 = 21. +64 = 85.) Current CV 48 value can be read back using the program track.
ES44AC / ES44DC & U18B
Use F8 to Start-Up Locomotive
CV 31 = 16 FIRST
CV 32 = 2 SECOND
CV 403 = 16
Loco remains quiet with track power. F8 must now be turned on to turn the sound on.
ES44AC / ES44DC & SD40-2
Ditch Light Flashing ON w/Horn
CV 32 = 2 FIRST
CV 316 = 128
Turns ON ditch light alternate flashing with the horn.
ES44AC / ES44DC & SD40-2
Ditch Light Flashing OFF w/Horn
CV 32 = 2 FIRST
CV 316 = 0
Turns OFF ditch light alternate flashing with the horn.
ES44AC / ES44DC & SD40-2
Ditch Light Flash Rate
CV 112 = 39 (1.95 seconds) Default Sets how fast the ditch lights alternate. Has an effective range of 1-255. A value of 20 = 1.00 second.
ES44AC / ES44DC & SD40-2
Grade Crossing Hold Time
CV 132 = 80 (5.2 seconds) Default Sets how long the ditch lights flash after the horn button is released. Has an effective range of 1-255.
SD40-2 LokPilot Non-Sound Decoder
Add Flashing Ditch Lights to F2
CV 32 = 2 FIRST
CV 386 = 1
CV 396 = 128
Adds alternately flashing ditch lights with F2 (horn key).
SD40-2 Ditch Light Brightness CV 31 = 16 FIRST
CV 32 = 0 SECOND
Set CV 278 & CV 286 to the same value between 1 (dimmest) and 31 (brightest). Default value for both CVs is 31 (brightest).
SD40-2
Air Bell to E-Bell
Activate F22 and then F1 OR
Set CV 32 = 2 FIRST
CV 302 = 0
CV 303 = 4.
CV settings change Air Bell sound to E-bell sound on F1.
SD40-2
Use F8 to Start-Up Locomotive
CV 31 = 16 FIRST
CV 32 = 2 SECOND
CV 419 = 16
Loco remains quiet with track power. F8 must now be turned on to turn the sound on.
All F units
Use F8 to Start-Up Locomotive
CV 31 = 16 FIRST
CV 32 = 2 SECOND
CV 387 = 16
Loco remains quiet with track power. F8 must now be turned on to turn the sound on.

Programming CVs Numbered Above 255:
Some Digitrax and NCE DCC systems cannot program CVs higher than 255.

Systems that CANNOT program CVs 255-511 include:
-Digitrax DT400 throttle with Zephyr Xtra or Zephyr
-Digitrax DT400 throttle with Super Chief or Empire Builder
-NCE PowerPro when programming on the program track

Systems that CAN program CVs 255-511 include:
-Digitrax DT402 throttle with Zephyr Xtra or Zephyr
-Digitrax DT402 throttle with Super Chief or Empire Builder
-NCE Power Cab on either the main or program track
-NCE PowerPro when programming on the mainline in Ops Mode

If you have a system that does not allow programming CVs higher than 255, ESU has implemented an assistance tool. You can use this method on either the program track or mainline with any DCC system and can program any number of CVs from 255-511 in sequence.

Set CV96 to the hundreds digit of the CV number that you are programming - The range is 0-9.
Set CV97 to the units and tens digits of the CV number that you are programming - The range is 0-99.
Set CV99 to the desired value of the CV that you are programming - The range is 0-255.

Once you set CV99, the values in CV's 96, 97, and 99 are reset back to 0.

EXAMPLE:
We want to set CV257 to a value of 6.

Set CV96 to 2 for the "200" range.
Set CV97 to 57 for the tens digit "5" and the units digit "7".
Set CV99 to a value of 6.


Cab Forward Sound Volume CV's

HO Scale LokSound Cab Forward Sound Volume CVs:
MASTER VOLUME: CV63 - Range: 0-192 - Default: 192
Indivdual Sound Volume CVs (MUST SET CV32 TO 1 FIRST!!):
Range is 0 (0%) - 128 (100%) for all sound volumes listd below:
Chuff #1: CV259 - Default: 110 (85.94%)
Chuff #2: CV267 - Default: 110 (85.94%)
Steam Whistle: CV275 - Default: 128
Bell: CV283 - Default: 99 (77.34%)
Coupler: CV291 - Default: 128
Dynamo: CV299 - Default: 128
Air Pump: CV307 - Default: 120 (93.75%)
NOTE: CV307 only controls the volume of the Air Pump activated by Function 10.
To change the volume of the Air Pump that plays automatically, see CV451 below.

Blower: CV315 - Default: 128
Injector: CV323 - Default: 40 (31.25%)
Crossing Communication: CV331 - Default: 128
Rail Clank: CV339 - Default: 85 (66.41%)
Brake Release: CV347 - Default: 128
Sand Valve: CV355 - Default: 100 (78.13%)
Oil Burner: CV363 - Default: 128
SP Air Horn: CV371 - Default: 80 (62.5%)
Short Whistle: CV379 - Default: 128
Power Reverse: CV387 - Default: 80 (62.5%)
Cylinder Cocks: CV395 - Default: 80 (62.5%)
Hiss and Start-Up: CV443 - Default: 110 (85.94%)
Brake Sound: CV459 - Default: 70 (54.69%)
Random Sounds: CV451 - Default: 128
CV 451 controls the volume of all Random Sounds INCLUDING the Air Pump that plays automatically at random intervals.

N Scale LokSound Cab Forward Sound Volume CVs:
MASTER VOLUME: CV63 - Range: 0-192 - Default: 192 (100%)
Indivdual Sound Volume CVs (MUST SET CV32 TO 1 FIRST!!):
Range is 0 (0%) - 128 (100%) for all sound volumes listd below:
Chuff #1: CV259 - Default: 110 (85.94%)
Chuff #2: CV267 - Default: 110 (85.94%)
Steam Whistle: CV275 - Default: 128
Bell: CV283 - Default: 99 (77.34%)
Coupler: CV291 - Default: 128
Dynamo: CV299 - Default: 128
Air Pump: CV307 - Default: 120 (93.75%)
NOTE: CV307 only controls the volume of the Air Pump activated by Function 10.
To change the volume of the Air Pump that plays automatically, see CV451 below.

Blower: CV315 - Default: 128
Injector: CV323 - Default: 40 (31.25%)
Crossing Communication: CV331 - Default: 128
Rail Clank: CV339 - Default: 85 (66.41%)
Brake Release: CV347 - Default: 128
Sand Valve: CV355 - Default: 100 (78.13%)
Oil Burner: CV363 - Default: 128
SP Air Horn: CV371 - Default: 80 (62.5%)
Short Whistle: CV379 - Default: 128
Power Reverse: CV387 - Default: 80 (62.5%)
Cylinder Cocks: CV395 - Default: 80 (62.5%)
Hiss and Start-Up: CV443 - Default: 110 (85.94%)
Brake Squeal: CV459 - Default: 70 (54.69%)
Random Sounds: CV451 - Default: 128
CV 451 controls the volume of all Random Sounds INCLUDING the Air Pump that plays automatically at random intervals.


Mapping Run 8 and Coast in the N scale SD40-2


As part of the ESU Full Throttle features included in the N scale SD40-2, Run 8 and Coast are not mapped to a function key by default. If you would like these features mapped, the following instructions map Run 8 to Function 13 and Coast to Function 14. Both of these functions are basically open in the decoder.

To do this set the following IN ORDER:
CV32 = 2 FIRST
CV490 = 0
CV496 = 8
CV512 = 16

If you would like Run 8 and Coast mapped to different functions, it is possible however some sound functions or lighting functions may have to be moved to different keys. This is very "custom" and is beyond the scope of this instruction. You can use the N scale SD40-2 function mapping table or give us a call.