WS-55315 with only red bulb

It seems that you donot have the 200+ V line for the GREEN,BLUE. This line is the same as the read line, check connectors located on crt boards make sure they did not come apart. Also you can:This model is equipped with a self-diagnosis feature to help with diagnosis of shutdown problems. To activate this turn the unit on let it shutdown then press the input and menu buttons on the front panel simultaneously and hold them in for 5 seconds after 5 seconds the power LED on the front panel will blink a two digit sequence. This will be one set of blinks a short pause then another set of blinks, this will repeat 5 times. 1 - 2 = no error detected 2 - 1 = X-ray protect (high voltage or beam current) 2 - 2 = Short protect (short protect monitors low voltage supplies) 2 - 3 = Deflection protect (this could be loss of vertical or horizontal deflection) 2 - 4 = Vertical protect (usually loss of vertical from the source) 1. Shutdown at power with self diagnosis error 2-2. Check for open fuses F9A04 and F9A05 part # 283P144080 on the +24 and -24 volt lines. If the fuses are open the convergence output circuit would be suspect. 2. Shutdown at power with self diagnosis error 2-1. At power on check for 12-volts DC at connector KH pin 8, if missing check IC9C51 part # 270P990010 and L9C52 part # 441D009020 on the Signal PCB