PCM Maxi-Fuse (30A) Blowing | Ford Explorer Forums - Serious Explorations

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PCM Maxi-Fuse (30A) Blowing


September 19, 1999
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Year, Model & Trim Level
1997 Ford Explorer
Anyone know what can cause the PCM Maxi-Fuse to blow?
I have a previous thread having to do with my 97 XLT 5.0 not wanting to run. I got to this point with help from the forum and would appreciate some more:

* I decided to disconnect the MAF connector. With the connector off, the engine started right up and idled smoothly. It wouldn't take much throttle, but that was not unexpected.
* I noticed that a couple of the connector wires were bent "funny" and checked them but they seemed to conduct OK. Then opened up the MAF and found that a spider had spun it's web around the sensor wires and blocked the air intake to the sensor. Cleaned that up with contact cleaner and tried again. Without the MAF connected the engine started and idled smooth. As soon as I plugged in the MAF connector the engine died.
* So I purchased a new connector and a new MAF. I just finished replacing the connector, having cut the harness wires back about 1" and splicing the new connector's leads to the harness wires. Soldered and shrink wrap.
Didn't plug in the connector 'cause I wanted to see if the engine would still idle smoothly without the MAF. It wouldn't start (cranks good, good fuel pressure).
* Noticed the Check Engine light wasn't on so I checked the PCM maxi-fuse. It was blown. Swapped in the fuse from the rear defroster (also 30-amp) and that one blew as well.
* So now I have that problem to deal with. Anyone know what can cause the PCM Maxi-Fuse to blow?

thanks again,,,