First, let me thank the FTE guys that got me on the right track with this last week. SECOND, let me start this post by stating that I found an electrical NIGHTMARE under my dash.

OK, I turn on the heater switch, it blows great, but only at one speed (high) for 5 minutes. Then it shuts off.

- I pulled the dash, looked at the switch: Two wires have been bladed (butchered) onto it: Positive and negative onto the 4 blade receptacle on the back of the switch. Where the rest of the plug or wires is, I don't know. I replaced the switch for good measure: Same results.

- I traced one of those wires underhood, it bypassed an old heater/AC control harness, and has a 30 Amp inline blade fuse in it. Where it goes from there, its hard to say, as its wrapped in 10 miles of electrical tape after that.

Im at a loss here folks, and its -7 degrees. If there are any FTE guys in the poconos/Lehigh valley PA area and you are a wizard with unscrewing electrical errors, I'll pay ya to come over and help me sort this out.

Thanks

 

Dig thru the tape to see where it goes. Sounds like the PO had the same issue and by passed it, but not to well.

Something fuse or relay related (?) is shutting off power, need to remove the hack job and find the original issue, pinched wire harness maybe?

 

99% of the time the culpret is in the blower resistor, when the connections get weak, those blades get hot and distort. eventually burning the terminals. On any old american car or truck the resistor is always in the blower housing and generally very close to the blower. It needs air flow to keep cool. The original culpret is the factory plugs, both on the resistor and the switch. and if it has a high blower relay, those go bad as well. I have always had good luck replacing all the ends with the regular crimp on blade connectors, just make sure they push on the blades really tight, if they don't crimp the ends a bit.

I would replace the switch and the resistor if there is any sign of burning on the blades, and the high relay as well.

 

I do not think I have stolen anything, I copied and pasted and I do not think I infringed on any copy rights? If I did I will give it back, lol.

Besides I only posted it to help another fellow Ford truck owner, what did you contribute to this thread. ZIP

And I have told ND and mike o0o0o0 I copy and all there stuff they post for my personal use. They never had an issue, why do you?