Overtemp on screen ?

I got setup to do some exhaust repair on a friends car .
I was using .035 wire [ but forgot I did not have the correct contact tip - .035 , tried to use .040 ] .

While welding / or trying , the wire would just sputter & never really melt base - just stick little balls of wire stuck to base ?
After trying for about 5-10 min. - the overtemp screen came on ?
So quit after that .

Now have more tips & using the correct tip .035 , also double checked the fluxcore setup / connections , turned the machine on and went to feed the wire through the gun & cable , look at machine and the overtemp sreen is back on - never cleared from the last time [ about a month ] .

So looking for ideas ?

Just for some backround , I took my 1st welding class in 1968 , many yrs. of welding most metals etc. & most all processes .

But this is my 1st inverter machine --- many more adjustments / than the past transformer machines in the past .

Likely wrong polarity. What unit are you using? But if it won't clear, you need to call tech support at ext 207 as soon as possible.

I have the MTS 225 .
I left out that I was setting up for flux core .
I did check & double check the connections in the manual , yesterday .
But the first time , about 6-8 weeks ago , I thought I did connect correctly - but too long ago to say for sure , but I did use manual then also , but possible .

I will call tech. in a couple hours , out of my timezone .

Thanks
John

Just to fallow up , tech. thinks it is a bad temp. sensor & they are sending one out ;)
Will post what happens .

Got the new temp sensor in just a few days ;)

Also asked where it was located - they sent a picture of a very similar board - so while waiting for new part , I opened up the case had to remove a couple boards & connections to find .
One of the deepest boards in side , found the cable connection & followed to an upper board - disconnected & did a Ohm test = 0.2 Ohms , when new one showed up I measured it at
0.3 Ohms - so the basically the same reading , and the extra work to get that board out to get acess to mounting screws - I left the old one in , and tried the welder with case off .

One other issue was that one of the ferrite beads was broken in half & laying on bottom of case - so rapped some tape around & put back on original location - I found that by a wire tie that was not holding anything .

Quadruple check connections & settings - and tried welding & making adjustments ---- all seems to be ok , now for the next project ;)

Not sure I found the problem - but it is working ?

Service was responsive & fast - thanks folks .