I have a 2005 Excursion Limited v10 with inoperable cruise control that I bought 2 years ago. Since I don't use the truck much, I'm just starting to track down the issue. I've read a lot of the threads here, and done the cruise control system test, and come out with a failed switch. The 2005 is NOT part of the master cylinder pressure switch recall.

However, in digging around, I have no wiring harness attached to the master cylinder pressure switch. I also don't have any loose wiring harnesses or obvious signs of any wiring just being cut off. Can anyone help me with wiring, where to look, where it should be connected or what I might need to purchase?



No wiring harness

 

Look in the area below the lower left shown in your photo, top of fenderwell. The pressure switch harness branches out of the same harness as the brake fluid level sensor and the MAF sensor, so follow those back and see what you find.

If the pressure switch circuit is open, the speed control is disabled.

 

Thank you! So, here's what I found...

There is a smaller harness that is looped back into the main harness. Picture 1. The loom only has 2 wires, and is clipped into a connector that appears to be factory bundled with the main harness. I disconnected it, and it's the perfect length to reach the pressure switch, and it fits the switch!

The connector on the main harness has no terminals in it, it's a dummy. Picture 2. Again, this doesn't look like something that a mechanic added afterward, it looks factory installed.

Do you think I've got the brake pressure sensor harness? If so, what is the purpose of the dummy connector, why might this have been disconnected? Think it's safe to connect to the pressure sensor and run through the cruise control diagnostics, and then a test drive?

Thank you!



Small harness comes out of the main loom and loops back to the main loom.




Dummy connector on wiring harness that the small loop connects to.

 

There is a recall for the cruise control wiring. They add a fuse in that harness. It could have been disconnected on purpose because the recall wasn't done. Call the local Ford dealer with your VIN number and they can look it up to see if it's been done on your truck.

It's an IMPORTANT recall, it can make your truck catch on fire.

 

Thank you, but no 2005s are part of the recall.

 

Recall 05S28 did NOT include the 05s since it didn't apply...

shmeek,

I've not seen or heard of your particular discovery before, but I suspect there's something in it's previous history (before you acquired it) that likely explains what you've found. Perhaps a wiring harness replacement or something else along those lines. Perhaps you can hook up with another 05 owner and compare what you've found... Wish I could offer additional insight.