The following guide will aid you with the installation of a standard Hornby decoder into the R2611 Class 142 Railbus Pacer.

Step 1. Locate and remove the fixing screw on the rear of the powercar, above the coupling mechanism.

Step 2. Gently remove the body from the chassis starting from the rear of the powercar and working forwards. There are small clips along the length of the chassis that will need to be worked free. When reaching the front, bend the chassis away from the body to unhook the headlight stalks.

Step 4. Remove the decoder from the protective packaging, taking care not to handle the PCB directly as this will cause irreparable damage due to static electricity. 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 and black 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 5. Remove the motor fixing bracket from the motor. This will give you improved access to the motor contacts. You may wish to remove the motor completely - if so, please follow the instructions included with the Pacer for removal and replacement of the motor.

Step 6. Unsolder the black wires going to each motor contact. The orange capacitor does not need to be removed, but is likely to come off when removing the black wires. If so, resolder it to the motor contacts once the black wires are removed.

Step 7. Solder together the two black wires that were connected to the first motor contact.

Step 8. Solder together the two black wires that were connected to the second motor contact.

Step 9. Solder the black wire from the decoder to the first pair of black wires.

Step 10. Solder the red wire from the decoder to the second pair of black wires.

Step 11. Solder the orange wire from the decoder to the first leg of the orange capacitor.

Step 12. Solder the grey wire from the decoder to the second leg of the orange capacitor.

Step 13. Replace the motor fixing bracket.

Step 14. Ensure none of the new joints are touching, 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 15. Secure the decoder against the locomotives chassis using BlueTack or an other suitable fixative.

Step 16. Insulate the areas where the black wires join to prevent short circuits.

Step 17. 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 between the chassis and the body. Test once more to ensure that the installation has been totally successful.