Forum Discussion

mich800's avatar
mich800
Explorer
Sep 03, 2016

Electrical Problem

I also posted this on a Ford fourm but I know there are some electrical guys here. See below:

This is one for the electrical gurus. 2008 F250 crew cab 6.4 with about 170k miles if this even matters.

Leaving the grocery store today we all got in turned AC on high and could smell something funny. Sat there for about 30 seconds trying to figure it out and realized it was electrical. But not like the typical smell I am used to when a wire is burning but very heavy smell coming out of the vents.

Now here is the weird thing. The electric door locks do not work from any switch or remote. If you use the remote it beeps like it locked but no lock or unlock. Fuses all check out unless I missed one. Here is the weird part; truck off, if you hold the unlock button down the radio plays. If you hold the unlock button on the remote the radio plays. How to I begin trouble shooting this?
  • Follow your nose. I highly suspect some wires have melted together and based on the pictures of a previous poster with a car b que, it may indeed be in the area of the resistor.

    This sounds like a very serious issue from an electronic techs point of view.

    You may be surprised how well your nose can track the source.
  • sorry about your fire hope things turned out ok, BUT ,I sure like the bronco in the back round.
  • enblethen wrote:
    The only item that should/could be in the air box, is the resistors that allows the fan speed to be changed.
    Some debris could have gotten on to the resistor as most are open wire type.


    I don't think that is what it was. I think whatever it was occured somewhere near where the AC was drawing the cabin air. I have everything opened up but cannot find any overt wire that fried. When you cycle the switch I can hear and feel a rely type click but it is behind the fuse box. it is not any of the relays on the fusebox.
  • The only item that should/could be in the air box, is the resistors that allows the fan speed to be changed.
    Some debris could have gotten on to the resistor as most are open wire type.
  • RoyB wrote:
    The FUSE LINK wire/cable is a fuse so to speak. If you have one of those as discussed above you need to measure the cable to see if it is open now...

    Roy Ken


    I guess I need to track down a wiring diagram to find the fuesable links. I think it would be crazy to have a fuseable link in the air plentum somewhere but anything is possible. AC was on Max or recirculate, so I think maybe somewhere close to where it was drawing intake air in the cabin.
  • RoyB's avatar
    RoyB
    Explorer II
    The FUSE LINK wire/cable is a fuse so to speak. If you have one of those as discussed above you need to measure the cable to see if it is open now...

    Roy Ken
  • SoCalDesertRider wrote:
    Sounds like a blown fuse, caused by whatever electrical short is resulting in the burning smell.

    If it's coming through the vents with the A/C on, it could be the resistor inside the heater box.

    Beware... that resistor likely caused the fire that burned one of my F350's to the ground....





    That is the problem. No blown fuses that I can find. But definatly something went wrong within the electrical that needs to be repaired. So far the only thing I can find not working are the power door locks. But when you use the lock/unlock button on either front door or remote you can hear the radio.
  • Sounds like a blown fuse, caused by whatever electrical short is resulting in the burning smell.

    If it's coming through the vents with the A/C on, it could be the resistor inside the heater box.

    Beware... that resistor likely caused the fire that burned one of my F350's to the ground....



  • Loo0k around the starter relay on the fender well. There is normally a couple of fuse links. could be fuses.
    One could be blown causing back feed condition.