Electrical problem, please help.

[vincentesq]

I have an 11 expedition. I installed a kenwood navigation system via I datalink maestro this morning and everything worked great! However, as I was cleaning up the wires, I probably shorted something. Now the navigation does not work anymore, I took it apart and tightened all the power and ground wires but still does not work. I check the fuse on the head unit, no problem. I checked all the fuses on the passenger compartment and all worked except #28, which is radio. However, I pulled out the fuse but it is not burned. I exchanged fuse, and it shows that the fuse on #28 is ok. Just that there is no power going to #28.
I'm assuming I shorted somewhere before the fuse box, but don't know what to do? Does anyone have any ideas ? Thank you.

 

[bricekin]

There is too fuse boxes. Make sure to check both. One under the hood and one in the vehicle.

 

[vincentesq]

Thank you, I've done that but I don't know which fuse to check. All the small fuse are ok, but the big rectangular ones, I don't know how to check.

 

[stamp11127]

Invest in a 12 volt test light or a dvm and we will guide you through testing the circuits.

 

[vincentesq]

I do have a 12 volt test light. Please tell me what Jo do next? By the way, is there another fuse somewhere out side the engine bay that might have been blown?

 

[bricekin]

The quickest way I use to test all the fuses in the boxes is by grabbing a Digital Multimeter (DMM) with the audio feedback for continuity. Set it for that setting and use the probes on the pair of posts on top of the fuses. You can do this without removing the fuse itself and if the fuse is good, you'll hear a beep. You don't have to look at anything and you know for sure if power is making its way through the fuse.

 

[vincentesq]

Found the problem, fuse 39 was also blown. Thank you Bricekin. Your advice helped me find #39.

 

[bricekin]

You're welcome. Glad you fixed the problem! Enjoy your new radio.