Does anybody have pics or a good description of the Glolwplug Feedback Circuit and any tips on how to clean or R & R this item?

is this what your looking for ??
http://ca.images.search.yahoo.com/images/view?back=http%3A%2F%2Fca.images.search.yahoo.com% 2Fsearch%2Fimages%3Fp%3Dglow%2Bplug%2Bsensor%26ei% 3DUTF-8%26rd%3Dr1%26fr%3Dfpca-ac%26fr2%3Dtab-web&w=421&h=341&imgurl=www.cs.rochester.edu%2F~jag%2Fvw%2Fengine%2 Fglowplugs%2Fglowplugs.jpg&rurl=http%3A%2F%2Fwww.cs.rochester.edu%2F~jag%2Fvw %2Fengine%2Fglowplugs%2Fglowplugs.html&size=36k&name=glowplugs+jpg&p=glow+plug+sensor&oid=b9c4e536d24fa976&fr2=tab-web&no=7&tt=74&sigr=1234ld2df&sigi=11rn3gim3&sigb=13847ef3b&type=JPG

It appears that only the CA emissions glow plug controller has feedback to the ECU.

Odds are if you are getting a P0380 you have at least one glow plug burned out. I'd recommend testing the glow plugs.

Hope this helps!

The glowplug feedback on the federal trucks simply sends power to the ECM when the plugs are on. All it looks for is if the relay is working and engaging. The CALI trucks have a glowplug controller that allows the ECM to monitor each plug individually.