Having trouble with my 30A fuse #5 blowing when in the glow plug heat cycle. Pulled the preheat relay and can crank over tractor all day without blowing fuse. Pulled NGK glow plug lamp timer relay and bench tested per previous threads and didn't light up at all with a test light - therefore suspect this is bad. Will this timer cause this 30A fuse to blow after a second or two of preheating the glow plugs? I verified power at the buss connection of the glow plugs for that timeframe until the fuse blows. New timer appears to be about $60-70 so wanted to make sure I didn't ruin it if something else was wrong. Looking at the wiring diagram it almost looks like this timer relay only controls the display light on the dash and doesn't shut off power to the glow plugs themselves. Does anyone have a better wiring diagram for this timer relay - NGK model no S81NF? Any better sources than the NH dealer for this part? Thanks for your help.