ECM-1 Fuse Blowing

Hello all!
Here's the quick run-down...
1999 GMC Yukon 73k miles 5.7L 4X4
Driving home today from shopping, the darn thing just quit on me...While
waiting on AAA for a tow, I did some troubleshooting. Checked all fuses and found ECM-1 (20A) blown. This appears to control the Injectors and the computer. I stuck in a fresh fuse, as soon as I got the key in the "on" position, there she blows.
Does anyone have any ideas where to start??
Other information that may be revelant: I just got back from 1100+ mile trip to Death Valley which included 40+ miles of back country off roading at speeds up to 50 mph but typically 25mph. Temperatures up to 90-110. 2 Severe dust storms... couldn't see 10 feet in front of the vehicle a few times. total time in storms maybe 90 minutes max.
Thanks
Bomber
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

The problem is most likely a chafed wiring harness shorting out to ground. Grab the wiring harness between the firewall and motor and give it a couple good tugs and see if the fuse holds. If the fuse still blows you will need to check for shorted components. If the fuse holds you will need to find the worn spot on the harness and repair it. I have found that the wiring harness is the culprit in most of these cases.
Rita
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Thanks Rita. Just after I posted this I pulled out my manuals. The "pink" wire was shorting out down near the Crankshaft Position Sensor.
Bomber
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.