Start by testing your programmer with the PIC and SX removed. Apply power to the programmer, ideally using a current limited power supply (100mA) or with a 100R resistor in series with VIN. The resistor acts a bit like a fuse is it will quickly burn out if there is a serious problem but should provide enough current to power the programmer if it's working properly.

1) Using a Voltmeter measure the Voltage between Pin5 (0V) and Pin14 (5V) on the PIC socket. This comes straight from the 78L05 regulator so if it's not 5V check the Voltages on the regulators input and output. If the output Voltage is too high it could be the wrong way around or the wrong device. If the output Voltage is to low you could have a short on the PCB or one of the electrolytics may be upside down.

2) Next measure the Voltage between Pin5 (0V) of the PIC socket and the 78L12 output. This should be between 13 to 13.5V, similar possible problems to 1) but also the output Voltage could be too high if the 1N4148 diodes are the wrong way around.

3) Now test VDD by measuring the Voltage between Pin5 (0V) and Pin14 (5V) on the SX18 socket. This should be 0V and VDD LED should be OFF. Now turn ON VDD by shorting (link) Pin7 and Pin5 of PIC socket. The VDD LED should come ON and SX18 Voltage should be between 4.5 to 5.5V. If the Voltage is correct but the LED does not come on the LED is probably the wrong way around. If the Voltage is always ON or incorrect then the ZTX500 transistor could be upside down or there is a PCB short.

4) Now test VPP by measuring the voltage between Pin5 (0V) and Pin16 (OSC1) on the SX18 socket. This should be 0V and VPP LED should be OFF. Now turn ON VPP by shorting (link) Pin18 and Pin14 of PIC socket. The VPP LED should come ON and SX18 Voltage should be between 13 to 13.5V. Similar problems to 3) but also the ZTX300 transistor should be checked.

5) Time to plug in the pre programmed PIC. The VPP LED should not come on but the VDD LED should flash twice (115KBS). The Voltage across the 100R input resistor should be less than 5V. If it's more than 5V you could have a PCB short on the PIC or one of the electrolytics may be upside down.

6) Remove the 100R resistor and connect to the PC serial port, run the IC-Prog software following the settings given in the software section.

7) If you are having problems connecting IC-Prog with errors like "error opening target" you should test the serial link. To test the serial link use a serial coms program like teraterm (ttermp23.zip) and follow the steps below.

Old SX chips
To use OLD SX parts (Date Code yywwxx) firmware version 2.3 or higher is required. It is important that VPP is >13V during programming otherwise it may not be possible to Erase or remove the chips Write protection. Test VPP as follows,

1) Insert the SX chip and select 'Read' from IC-Prog. VCC and VPP LEDs should come ON.
2) Measuring VPP between Pin5 (0V) and Pin16 (OSC1) on the SX18 socket. This should be >13V and <13.5V (typ. 13.2V).

3) If the voltage is <13V check the power supply voltage (>18V). Also check the voltage out of the 78L12 (>13V and <13.5V).

4) If VPP is still <13V change the PNP transistor (ZTX500) that drives OSC1.

Serial link testing the with Tera Term
1) Start TeraTerm.
2) Select 'Serial' and 'COMx' port.
3) The serial settings are not important as we are just trying to do a loop-back, but try,
        'Setup' -> Serial port -> COMx, Baud-9600, data-8, parity-none, stop-1, flow-none

4) Plug the serial lead into the COM port you are using (D9 connector) but NOT into Fluffy2.
5) Link pins 2 and 3 on the serial lead 'loop-back'.
6) Type at the keyboard and this should echo to the screen,
    If this works remove the link and this should stop the screen echo.
    If this does not work you have a port conflict or faulty lead and should try other ports/leads.

7) Now plug the serial lead into Fluffy2.
8) Remove the PIC and link pins 1 and 10 on the PIC socket. Power up Fluffy2.
9) Type at the keyboard and this should echo to the screen,
    If this works remove the link and this should stop the screen echo, the test is now complete...
    If this does not work you have a problem with the serial wiring or something around the MAX232.