LG 42PC1DV stuck in standby

[markc]

Hi,
this set is stuck in standby, blue led flshes but set does not turn on. Replaced 9 faulty capacitors in the PSU, but still the same. Suspect it may have corruped the eeprom or some other damage. Customer did leave the set on with the fault for 3 hours to see if would repair itself!!
I notice there are 3 tact switches on the main panel, is one a reset?
Any help much appreciated.
Mark