When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
No start diagnosis leads to random number generator
Van was idling just fine and then just died. No start, no wts light. Troubleshooting with DMM shows the following sudden issues:
Main junction box fuse is HOT at all times. It's supposed to only be hot with ignition at run/start
Break in line between main junction box fuse and PCM diode
WTS light doesn't turn on power is manually applied between main junction box fuse and PCM diode (van will start and run fine if I do this, but WTS light no longer functions, and cannot turn off van without pulling main junction box fuse)
Any idea how I can get all three of these wiring issues all of a sudden?
Seems too unlikely I would have 3 seperate wiring issues spontaneiously appear unless there is a single issue that's causing all of these symptoms. I can't figure out anything from wiring diagrams on how these 3 systems could be related.
Have you checked the ignition switch connector to see what wires have power in what key positions? I could see some type of short or power surge fusing some contacts in the switch or one of the little slide contactors jump track and is ”crossing wires' internally.
What's the best schematic tool for doing this sort of electrical troubleshooting? Th factory manual feels like a scavenger hunt where i have multiple pages I'm flipping through to trace just a part of one circuit... And it doesn't show everything that's attached to the circuit, just the bits that are relevant to the selected diagram.
I checked the ignition switch, and it's fine. However, somehow every single line that comes off the ignition switch is shorted to power, even with the ignition switch unplugged. Not sure how that's possible
I can't find any documentation of the existence of a battery junction power relay fordtruckn00b. Is this a truck only thing? Seems to be two main power lines in the battery junction box, and no relay for either of them.
Ok so i fixed it. And it makes no sense to this moment how i didn't realize i was looking at the wrong #8 fuse this whole time (under dash vs under hood). I guess I'll just admit I'm a bonehead that spent a month on this and disassembled half the engine bay for nothing.
I unplugged the fuel bowl heater and replaced fuse #8 and I'm back in business. Thank you all for your help and sorry for wasting your time.
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.
