4-6 Phaser 4500/4510 Service ManualGeneral TroubleshootingTroubleshooting ProcedureSteps Actions and Questions Yes No1 Check the 24 V input:1. Remove the LVPS Shield Plate(page 8-60).2. Disconnect J404A from P404 (in-lineconnector).3. Turn the power ON.4. Measure the voltage across J404A-3<=>J404A-2Does the voltage measure 24 VDC?Go to step 2. Go to “LVPS(Low VoltagePowerSupply)” onpage 4-4.2 Check the 3.3 V input:1. Disconnect J40 from the LVPS.2. Turn the power ON.3. Measure the voltage across P/J40-3 <=>P/J40-4.Does the voltage measure 3.3 VDC?Go to step 3. Go to “LVPS(Low VoltagePowerSupply)” onpage 4-4.3 Check harness A, 24 V Input:1. Turn the power OFF.2. Disconnect J404B and J403.3. Check each conductor in the harness forcontinuity.Is each conductor continuous?Go to step 4. Replaceharness Afrom theLVPS(page 8-62).4 Check harness B, 3.3 V Input:1. Turn the power OFF.2. Disconnect P/J40 on the LVPS andP/J401 on the DC-DC converter.3. Check for continuity across the following:■ P/J40-3 <=> P/J401-2■ P/J40-4 <=> P/J402-1Are both conductors continuous?Go to step 8 Replaceharness B.5 Check harness C, output to imageprocessor board:1. Turn the power OFF.2. Disconnect P/J402 on the DC-DCconverter and P/J130 on the I/P Board.3. Check for continuity between P/J402 andP/J130Are all conductors continuousReplace theDC-DCconverter(page 8-63).Replaceharness C.
