I was about to adjust the "idling Screw" on my 1990 Nissan Pickup, when I suddenly noticed that the engines RPM's increased. I went and "wiggled" the wire on the IACV, and the engines RPM then dropped. I found out that this IACV was faulty and causing the engines RPM to go up and down. But in the process of doing that the wires must have shorted out, because the terminals on the" idle air control Valve" turned RED HOt at that same time the Positive battery terminal arched and the engine cut off. I checked the headlights, interior lights the horn and they all worked, except for the ignition. When I turn the key to the "Ignition" all it does is,....... NOTHING!!!!!. Can anyone help me out with this problem ? Thank You

Maximum RPM

Check on the fusible links under the hood. After the short they sometimes blow. You can look though a clear window at the fuse before removing the contact bolts on each side to replace.

Thanks for your help and reply Mr.Timothy I was able to locate and correct that blown " Fusible Link " I may be criticized for this, but I replaced the " Fusible Link" with a standard " Blade Fuse" holder" a 5 Amp fuse blew just turning the ignition on. The 10 amp blew when I test drove the truck in my driveway. But the 15 amp held. Oh! and as for the IACV,..... I disconnected it for the time being, so that I can get the vehicle on the road.