Help finding light part number for SW9 railking switcher

Assuming it is a PS2 model it is a 6V lamp , part number CA0000074. It will likely have a connector, however the wire length will vary.

you can find the part at www.mthpartsandsales.com

Thank you,

Mike

Upgrades to existing models, should consider TMCC/DCS track voltages of 20 volts or slightly larger.  While traditional layouts operated at 12 VAC.  TMCC/ DCS track systems operate at higher voltages, which would tend to "short life" incandescent lamps.  IMO, Mike CT. 

Mike I seem to have an older one - will that part still work?

Yes, it is a PS1 locomotive, but Mike is still correct, it is a 6 volt lamp. If you can solder, you can by-pass the plug and solder the bulb wires directly to the end of the circuit board where the socket is and route the wires to the rear headlight.

So you know what I have learned: PS1, PS-2 (5V and 3V) and PS3/2 Stacker boards (5V and 3V) all use 6V grain of wheat lamps for headlights, ditch lights, cab lights, firebox glow (any diesel strobe/beacons are LED’s).

You can find a complete listing of incandescent lamps if you search exploded view diagrams for “Lamp Guide”

Diesel PS-3 boards & Production PS-3 steam boards (where you have a main tender board and boiler board) all use LED lighting. You can find a complete list of LED’s if you search exploded view diagrams for “LED Guide”

Hoping to make a few additional lists like this for wireless drawbars, 3/2 feature trucks, etc. to help everyone find the “common” parts easier.

Thank You,

Mike Reagan

MTH Parts & Sales LLC

I failed to mention that RK steam locos that have PS-1 typically used an 18V lamp for the headlight. (Its still shown on the Lamp guide)

premier locos that have micro-miniature green, ref or amber marker/class lamps are LED’s and they appear on the LED guide.

Thank You,

Mike

Ok, Time for bulb refresher for everyone.  PS-2 3V and 5V and PS-32 use 6V bulbs.  PS-1 has a lot of variations. First.  If directional lighting (headlight and reverse light) are driven from the bottom of the PS-1 board blue and green connectors they are 1.5V bulbs.  Otherwise they normally are 18V bulbs driven off track power and not directional.  Like RK Steam engines headlight.  This also applied to some RK diesels.  Using Bayonnet bulbs and even GOW bulbs.

IF there is a Constant voltage board like Premier steam and diesels and sometimes RK then the bulbs are 6V.  In diesel this is typically a cab light, number boards and sometimes even the marker (when driving leds there is a current limit resistor on the CV board).  So trace the source of the power.  If on the PS-1 board it is 1.5V, if CV board 6V, if track power 18V.

PS-1 Steam may have 18V or 6V on engine, but usually if a directional tender backup light it is driven off the PS-1 board in the tender.  Marker also driven off the yellow connector on PS-1 bottom board.

Now the last variation is the DCRU which is what the op has.  It is not PS-1.  Some 30-xxxx-0 engines had a modified DCRU that has a 6V regulator add to the bottom of the DCRU.  This provides 6V source for lights.  So basically like a CV board but actually built into the DCRU.  If not a modified board, the bulbs would be 18V driven off track power.

So trace wires.  G