Kato Class 373 Eurostar

Mistakes may damage your locomotive, controller or other accessories. Use a multimeter to make absolutely sure you have completely isolated the motor from the track before testing. Always use the Programming Track for testing. Our guides are provided for reference only, and you proceed entirely at your own risk. Unsure about something - try our DCC Conversion Service instead.

This guide shows how to convert the excellent Kato Class 373 'Eurostar' models to DCC, and includes motor and directional lighting control. There are two versions of this model which are exactly the same electronically: the original white and yellow version from the early nineties, and the dark blue version. Electra Rail also do vinyls that can be applied to convert the model into GNER livery they had when leased for Leeds-London services for a period.

This guide covers all versions of the Kato Eurostar model, which are identical other than the liveries applied:

• Class 373 e300 3201 Eurostar in original white/yellow/blue livery (10-327)
• Class 373 e300 3005 Eurostar in original white/yellow/blue livery (10-1295)
• Class 373 e300 3015/3016 Eurostar in post-2013 blue/grey livery (10-1297)

Digitrax produce a swappable PCB for converting this model to DCC (DN163K0a), however it is expensive and still requires some modification to make it work. For example, it is supplied with two white LEDs (one of which is pointing in the wrong direction) so the original red LED needs removing and re-using from the stock PCB. Geoff at Flint Hills has described how to perform the DCC conversion using the Digitrax board. The steps shown there for converting the directional lighting in the dummy power car are incorrect and will not work as shown in the video. This is because as manufactured, the directional LEDs are fitted with opposite polarities.

This guide uses a Doehler & Haass PD10MU-3 decoder, which is very small. Any other small decoder with light functions will work too, such as a Zimo MX615. The procedure for converting the power car and dummy car are broadly the same, with the exception that obviously you don't need to connect a motor in the dummy car.

Step 1 - Remove the body

Remove the body by gently prising upwards. Note that there is a thin grey piece of plastic trim on each side - the point to get your thin plastic pry tool in is just above that. Once the body has been popped off, these plastic pieces of trim can be removed by sliding them towards the back of the loco. Note the layout of the stock PCB - the red LED is at the front, and the white LED is right in the middle.

Step 2 - Remove PCB

To remove the PCB, gently remove the grey plastic clip just in front of the white LED. Bend the motor contacts up slightly to help it pop out.

Step 3 - Isolate Power Rails

As with many Kato models, there are two 'rails' that run the entire length of the unit to provide track power to any PCBs or sub-assemblies. These rails need to be isolated from the motor contacts. Pop them out by pushing the outer black clips holding them in place towards the middle. Remove the capacitor that bridges the two rails. Wrap some Kapton tape around the rails so that when the motor contacts are bent back, they cannot make an electrical connection.

Step 4 - Connect Track Power

Temporarily fix the decoder to the rear of the loco, ensuring that it is completely isolated from the metal chassis. Solder a red wire from the decoder to one of the power rails, and a black wire from the decoder to the other. Refit the rails by putting the plastic clips back in to secure them. It is possible to take track power from the outer tracks on the PCB, but this method is more reliable as it doesn't rely on pressure on the contacts. See below for an example of this on the dummy car, for illustration purposes.

Step 6 - Modify PCB

Cut the tracks on the PCB as shown. Use a multimeter to check there is no longer continuity between the two parts. Solder the lighting common (blue) wire from the decoder to the outer side of the PCB where the resistor is. Solder a blue link wire as shown. Solder the white directional lighting wire to the track on the red LED side, and the yellow wire to the white LED side. For the dummy car, the white and yellow wires are reversed.

Step 7 - Connect Motor

Solder the orange and grey (motor) wires from the decoder to the motor tabs, and add some heatshrink sleeving to cover the join. Tidy up the wires and move the decoder so that it takes up the space just behind the PCB. Before testing on your test track, check that there are no shorts and that everything is properly isolated.

Step 8 - Reassemble

Refit the body, remembering to slide the long thin plastic trim pieces on each side before clipping the main body back onto the chassis.

Step 9 - Convert Dummy Car Lighting

The process for converting the dummy car is broadly the same as for the powered one. The main differences are:

• No motor to connect
• Red and white LED connections are reversed, i.e. yellow wire to red LED and white wire to the white LED
• More space inside the body for the decoder

Step 10 - Test

Place the powered and dummy locos on your test track. Confirm that the loco runs in the correct direction, and that the directional lighting is correct for the direction of travel. If the loco runs in the wrong direction, simply reverse the orange and grey wires in the powered end. Alternatively, you can use CVV programming of your decoder to reverse the direction.

If the directional lights are reversed, i.e. the loco shows a red light at the front, and white at the rear, then you can either reverse the yellow and white wires in whichever end is affected, or you can use CVV programming to swap them round

It is possible to omit the blue link wire on the PCB, by desoldering the LED it is connected to, reversing the legs and soldering it back in. Note that this requires the track providing a path back to the resistor not to be cut, otherwise one of the LED legs doesn't go anywhere.

Our DCC Conversion Service