Step 1. Carefully remove the body by gently pulling the body sides apart and then pulling the chassis down.

Step 2. Locate the orange capacitor situated on the side of the motor. The capacitor has three wires attached to each "leg". Bend the capacitor away from the motor to make the attached wires accessible.

Step 3. Unsolder the three red wires from one leg of the capacitor as shown. If these wires become unsoldered from each other in the process, simply resolder them ready for fitting the decoder.

Step 4. Unsolder the three black wires from the other leg of the capacitor as shown. If these wires become unsoldered from each other in the process, simply resolder them ready for fitting the decoder.

Step 5. Remove the decoder from the protective packaging, taking care not to handle the PCB directly as static electricity will cause irreparable damage. It is important to protect the decoder by wrapping the PCB with insulating tape. To prepare the decoder, remove the plug and separate the red, black, orange and grey wires. The rest can but cut as short as possible and insulated with a piece of insulating tape. Strip the red, black, orange and grey wires and lightly "tin" them with solder. Tinning the wires will make the installation easier. When soldering care must be taken not to breathe in the fumes.

Step 6. Solder the black wire from the decoder to the three black pick up wires as shown.

Step 7. Solder the red wire from the decoder to the three red pickup wires as shown.

Step 8. Solder the grey wire from the decoder to the first capacitor leg as shown.

Step 9. Solder the orange wire from the decoder to the second leg of the capacitor as shown.

Step 10. Ensure that none of the new joints are touching each other or any metal parts and place the locomotive onto the programming track and test to make sure that the installation has been successful. Remember that the decoder has a default number of “3” and it is recommended that you code the locomotive to the number you require and test again.

Step 11. Insulate all solder joints as shown and secure the decoder against the locomotives chassis using BlueTack or an other suitable fixative.

Step 12. Place the locomotive onto the test track and test again. Once you are satisfied that the decoder is functioning correctly, replace the loco body, ensuring that there are no wires caught in any moving parts, or 'pinched' between the chassis and the body. Test once more to ensure that the installation has been totally successful.