Auto Idle won't idle on Miller 44D

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Replaced cicuit board and auto idler switch..not sure what to do next. The machine will not drop in RPM to 1100 but continues to idle at 1800 as if laying a bead
Reply:Welcome to the forum lumberwonder.Working systematically, check the following:1) Make sure the GTAW/SMAW mode selector switch is set to SMAW.  Auto Idle doesn't function in TIG mode.2) If still no go, with mode switch in SMAW, confirm battery (+) voltage at Auto Idle switch input (wire #76).  If no voltage, work backwards to locate cause.3) If voltage at/thru Auto Idle switch in "ON" position, confirm battery (+) voltage at control board PC1 terminal "B" (wire #48) and terminal "C" (wire #97) and battery ground (-) at terminal "J" (wire #42).  Voltage at wire #97 may be less than full battery voltage depending on system state.4) Confirm battery (+) voltage at engine idle solenoid plug (wire#48 ?) with switches in same position as in 1) and 3).5) If battery (+) voltage in 4), grounding the other side of the solenoid plug (wire #47) should cause the solenoid to activate.  If it activates, idle control board PC1 is likely bad.6) If solenoid does not activate in 5), check for continuity of the solenoid coil with a Volt Ohm Meter (VOM) on the Ohm setting.  No continuity indicates a failed solenoid.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:Thanks Duane will try and advise as to how We made outLumberwonder
Reply:ended up changing fuse holder and it now starts correctly and idles perfectly..unfortunatly when one strikes an arc it will not increase speed to 1800 RPM. We can change the setting on the auto idle switch and the welder will idle in one position and speed up ;to 1800 RPM in  the other position.ThanksBob A