If it is indeed the #9 fuse that is blowing then there is a problem with the PCM or any of the following PCM Power Relay, Electronic Transmission Control, Injector Pressure Regulator, Injector Driver Module.
The fuel heater is on the #22 fuse.
96 F250 PS XLT 4X4 long box, 5sp,4.10, manual hubs,pyro+boost guages, Dark Toumaline, add a leaf, Dale's TYMAR, and HX hose, downpipe, coolant filter, Luk clutch
yes it is the #9 fuse and with more research i am finding that it points towards the ecm like you said. We unplugged the ecm and the fuse still blows instantly. I know thats pretty much a dead short but was just hopeing someone else had this issue and could relate, thanks for your info. Now to find a good schematic and go from there!
Last edited by woftracing; 02-18-2013 at 05:43 AM.
The Electrical and Vacuum Troubleshooting Manual would help you out here! If the fuse was blowing with the PCM disconnected, it is probably not the PCM (more likely a wiring short upstream of the PCM). If you don't mind sacrificing fuses, see if the fuse still blows when the PCM Power Relay is pulled. If it does, you will need to check for a short on circuits 37 (output side of underhood fuse #9 to power input side of the PCM Power Relay and to pin 55 on the PCM. If it doesn't blow, pull the IDM Relay and reinstall the PCM Power Relay. Does it blow then? If it does you will need to check for a short on (as mentioned) the IPR circuit, PCM power (PCM pins 71 and 97), IDM Relay Coil input, and Transmission Control for an automatic. Cheers!
97 F250 SC 4x4 (CA model), E4OD, 4.10 LS, Relocated Block Heater Plug, Ext Trans Filter, Tru-Cool Max, I/C Mounted but not Plumbed
You still need to unplug the IPR, IDM, and the connector that goes to the transmission if you have a automatic. And then check if there is still a short.
This. Instead of unplugging one thing at a time, which could blow a lot of fuses, start by unplugging everyting associated with the fuse, then plugging things back in one at a time, turning the key to RUN and back to OFF each time. One of those times, the fuse should blow. 'Course, if it blows with everything unplugged, then you've got a chafed wire shorting to ground somewhere, most likely.