Maintenance check CPU + 5 v and reset signal and clock oscillation are no exception, peripheral circuit components is no bad, doubt there is something wrong with the dashboard, focusing on IC1 (HD404316B38S)} {26 ~ 35} {script machine keying the gate end and diode D14 ~ D22 via CON03 to film light touch control level and resistance of the conductive operating extremely, including CDN03 {2} and {5} feet without TP signal output, when the normal measurement with multimeter MF30 type R x 10 k, the positive meet {5} the table, the cathode by {2} feet, press any key at the same time the client should be Ω 500 m to 500 m Ω resistance value changes, but the measured all the keys are not change, the conductive pole has gone bad. Because of using conductive pole from viscose glue them into a can therefore regenerative repair, maintenance carefully first broke the plastic film and is the key contact have black coating. Rubber wipe and trial, the contact is intact, and adhesion after electrify commissioning, each function keys all return to normal operation, troubleshooting.ApAservice manual download site