Updating the Zimo equipped Class 60 with headlights automated to only switch on when the loco is on the move and adding a "Yard lighting mode" (both front markers on without the headlights).



A thread in the RMweb forum, initiated by Norm81, revealed that the headlights of Class 60 locomotives are only enabled when the locomotive Master switch is changed from neutral to Forward. The marker lights stay on while that switch is in the neutral position. This is why photographs of stationary Class 60 locos often show the headlight in the off state, while the opposite side marker light is clearly on.  This provided an interesting lighting challenge.... complicated by the classic Hornby negative ground lighting PCBs (unless of course your 60 was sound equipped from new, in which case its all a lot easier as the lighting PCBs on new sound 60s have decoder friendly positive ground.)

So the first task is to reconsider the overall lighting requirement. Next, to come up with a hardware solution and finally to find the best way to get the Zimo decoder to provide output(s) that only switch on when the loco is on the move. (Easy within the normal function mapping arrangements on a LokSound V4, but at first sight, I didn't have an obvious solution on the Zimo decoder!..... sorted now!)


DB Schenker liveried Class 60 as received. The intended recipient of the modified lighting system.


The Lighting Requirement:

My Class 60 has a tension lock coupling at the rear (end 1) but has non operational cosmetic couplings, hoses etc at the driver's end (end 2).  So a train will only ever be coupled at end 1 and the loco can only double head if in the lead position. Therefore I only need the ability to disable the running lights at end 1. (Mainly when hauling a train). So the requirements can be summarised as follows:

Light engine: Directional running lights at both ends with day or night switching but appropriate headlights only active when the loco is not stationary.

When in train hauling mode: As above but with all running lights at end 1 disabled.

Cab light (at driver end 2 only): Independently switchable but disabled if the locomotive is not stationary.

Note: Forward running lights when on the move consist of either day headlight on right hand side plus day marker light on left hand side. OR night headlight on left hand side plus night marker light on right hand side. When the locomotive is stationary, the headlight is not illuminated.

Yard Operation mode: Both front markers on together but no headlights! (light engine and in train operation.) (Headlights are kept off to avoid dazzling yard staff.)

Yard Super-shunter mode: All 4 markers and all 4 rear lights on simultaneously (no headlights). (Headlights are kept off to avoid dazzling yard staff.)


The Hardware solution:

1) Independent access to the headlights:

In the original PCB, the headlight and marker light combination consists of two white LEDs, each with its own small series resistor (33 ohms) connected at the anode. The LED and series resistor pairs are connected in parallel, with both LED cathodes hooked up to the common negative track and the two series resistor ends hooked up to a positive control pad.  See diagram below:

Original Lighting PCB circuit (Much larger external series resistors are used to define the total LED current.)


Photo of an earlier version of the same PCB with spring contacts (now replaced by plain solder pads)


The headlight LED anodes can be isolated by removing R2 and R5. Anode interconnect wires then need to be soldered to the R2 & R5 pads nearest to the edge of the PCB.




Circuit Solution:

For my third go at a solution: This is a simple update to the original circuit in my Zimo 60 and it appears to give enough flexibility to handle the information on operational lighting received so far.

Using P-channel MOSFETs in place of the PNP bipolars, could save a few resistors.


FO7 uses Zimo's "only on when stationary" feature, to disable all headlights when stationary.

Swiss mapping is used to group the required combinations of lights for the required lighting modes.



Updating the hardware:

At each end, a couple of extra resistors and two new diodes are added, while SMD resistors R2 and R5 are removed and their outer solder pads are wired back to the new parts on the back of the cab bulkhead.

Rear bulkhead of number two end cab, ready to be wired in again.


It would be a much neater job with SMD components!



Programming Changes:

This section is revised to take advantage of a Zimo firmware upgrade to version 34.10, which has 13 Swiss mapping groups, which enables a better lighting control arrangement to be used.

Summarising the lighting requirement:

Lighting mode Description Forward FO Reverse FO Swiss Group Function Key
Cab light (driver's end 2 only) FO5 FO5 - 8
Parking rears both ends FO3, FO4 FO3, FO4 - 0
Headlights operate only when loco is moving. FO7 FO7 1 19
Day running Lights (light engine) H/L, FO4 R/L, FO3 2 20
Night Running Lights (light engine) FO1, FO4 FO2, FO3 3 21
Train Haul day (coupled at end 1) H/L FO3 4 22
Train Haul night (coupled at end 1) FO1 FO3 5 23
Yard mode (light engine) H/L,FO4  R/L,FO3 6 24
  FO6, FO1 FO6, FO2 7 24
Yard mode train haul H/L, FO1 FO3 8 25
  FO6   9 25
Super shunter R/L, H/L H/L, R/L 10 26
  FO3, FO4 FO3, FO4 11 26
  FO1, FO2 FO2, FO1 12 26
  FO6, FO6 13 26

 Conventional Mapping:

NB: requires F8 to be available.....if its not, use any other available key up to and including F 12 and amend the FO5 key assignment quoted below.

Description CV Value
Mapping Mode 61 97
Key 0 fwd assignment (FO 3 & 4) 33 48
Key 0 Rev assignment (FO 3 & 4) 34 48
Key 8 assignment (FO 5) 42 64


Swiss mapping:

Description CV Value
Group 1      F-Key 430 19
M-Key 431 0
1st fwd FO 432 7
2nd fwd FO 433 0
1st Rev FO 434 7
2nd Rev FO 435 0
Group 2     F-Key 436 20
M-Key 437 0
1st fwd FO 438 14
2nd fwd FO 439 4
1st Rev FO 440 15
2nd Rev FO 441 3
Group 3      F-Key 442 21
M-Key 443 0
1st fwd FO 444 1
2nd fwd FO 445 4
1st Rev FO 446 2
2nd Rev FO 447 3
Group 4      F-Key 448 22
M-Key 449 0
1st fwd FO 450 14
2nd fwd FO 451 0
1st Rev FO 452 3
2nd Rev FO 453 0
Group 5      F-Key 454 23
M-Key 455 0
1st fwd FO 456 1
2nd fwd FO 457 0
1st Rev FO 458 3
2nd Rev FO 459 0
Group 6      F-Key 460 24
M-Key 461 0
1st fwd FO 462 14
2nd fwd FO 463 4
1st Rev FO 464 15
2nd Rev FO 465 3
Group 7      F-Key 466 24
M-Key 467 0
1st fwd FO 468 1
2nd fwd FO 469 6
1st Rev FO 470 2
2nd Rev FO 471 6
Group 8      F-Key 472 25
M-Key 473 0
1st fwd FO 474 14
2nd fwd FO 475 1
1st Rev FO 476 3
2nd Rev FO 477 0
Group 9      F-Key 478 25
M-Key 479 0
1st fwd FO 480 6
2nd fwd FO 481 0
1st Rev FO 482 0
2nd Rev FO 483 0
Group 10     F-Key 484 26
M-Key 485 0
1st fwd FO 486 14
2nd fwd FO 487 15
1st Rev FO 488 14
2nd Rev FO 489 15
Group 11      F-Key 490 26
M-Key 491 0
1st fwd FO 492 3
2nd fwd FO 493 4
1st Rev FO 494 3
2nd Rev FO 495 4
Group 12      F-Key 496 26
M-Key 497 0
1st fwd FO 498 1
2nd fwd FO 499 2
1st Rev FO 500 1
2nd Rev FO 501 2
Group 13     F-Key 502 26
M-Key 503 0
1st fwd FO 504 6
2nd fwd FO 505 0
1st Rev FO 506 6
2nd Rev FO 507 0

Other essentials:

CV131=60 to automatically switch off the cab light (FO5) when the loco moves.

CV159=60 to make FO7 off when stationary and on when moving.

Remove fader key from F19:  Set CV313 to zero.

Add volume down to key F27:     Set CV396=27

Add volume up to key F28:      Set CV397=28


Lighting mode Description Key

For automatic headlight shut down when stopped....

Cab light (driver's end only)           (Auto shutdown when moving.) 8  
Parking rears both ends 0  
Day running Lights (light engine)      20 Also use key 19
Night Running Lights (light engine)    21 Also use key 19
Train Haul day (coupled at end 1)     22 Also use key 19
Train Haul night (coupled at end 1)     23 Also use key 19
Yard mode light engine 24  
Yard mode train haul 25  
Super shunter 26  

Note: If all operations are required to automatically shut down the headlights when stationary, simply leave key 19 pressed



Revised Function Mapping:

Key Action
0 Parking lights (Rears on at both ends)
F1 Engine start/stop
F2 Braking Key
F3 Horn hi tone (playable)
F4 Horn lo tone (playable)
F5 Notch 1
F6 Notch 2
F7 Notch 3
F8 Driver's Cab light (only enabled when loco is stationary)
F9 Flange scrape
F10 Brake Air Release
F11 Coupling
F12 Spirax valves
F14 Momentum reduced for light engine
F15 Sanders
F16 BIS (Pre start engine priming)
F17 Dispatcher whistle
F18 Door open & slam
F19 Activate for automatic switch-off of headlights when loco is stationary
F20 Day running Lights (light engine)
F21 Night running lights (light engine)
F22 Day running lights, train haul (driver's end 2 at front)
F23 Night running lights, train haul (driver's end 2 at front)
F24 Yard mode lights (light engine)
F25 Yard mode lights, train haul (driver's end 2 at front)
F26 Super shunter mode lighting
F27 Volume down
F28 Volume up


To see a demonstration video, please click on this line.......


Subsequent to the video, another super shunter lighting mode became apparent, this is now incorporated into the design and included in the above information.


To see a demonstration video of the super shunter etc, please click on this line.......

Super Shunter Mode (now also incorporated).



Supplier website links:  


Hornby The DB Schenker Class 60 unit above was purchased early, direct from the Hornby shop, when this was the only source.
Digitrains A good source of all things DCC including pre-wired chip LEDs from DCCC and Zimo decoders.
Rapid Electronics A good low cost, high speed supplier of electronics components etc
Maplin A convenient local source for electronic components such as resistors and transistors




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