Half the electrical stuff is dead...please help!

[the_sarge]

I'm scratching my head here, I hope someone can help. A couple of days ago I was cruising down the interstate and lost dash lights, radio, windows, and heater fan. I have a 2005 GT with 130K miles.Here's what is NOT working: DRLs, gauges, turn signals, power windows, moonroof, heater fan, AC, power mirrors, stereo (Clarion CX609)Here's what IS working: HI/LO beams (turned on with switch), tail lights (with headlights on), horn, dome light, stereo illumination, HVAC control lights, hazards, door chime, keyless entryAlternator checked bad on my charger/tester and at Autozone. I've had the battery light on very dim for a while now. Replaced the alternator, belt, and belt tensioner assembly. No fix. Still had very dim battery light, and new alternator checked bad on my tester. Seems like a remote possibility that a new alternator would have exactly the same problem as the old one...Battery is 2 1/2 years old.Checked the 100A fuse, OK. Checked continuity/resistance of wire from alternator post to positive terminal on battery, OK (less than 3 ohms resistance). Checked every fuse under the hood with a multimeter, OK. Checked gauges fuse with multimeter, OK. (Will check the rest of the interior fuses tomorrow)Slaved in my RV battery I had on the charger in the garage. No fix, but I did not have the battery light. I'm stuck, I hope someone can help...thanks. Time for a cold one (or two or three or...)

[Sublimewind]

Without knowing if any of the other fuses are blown, we'd be shootin at the moon..

[the_sarge]

Yeah, I visually checked all the dash fuses. They all looked OK. I'll hit them with a multimeter to verify.

[djkeev]

Open the hood, on the left front fender is a covered relay box that also has fuseable links (BIG fuses) in it. Take a look and make sure none of them are blown. They can control massive amounts of electrical items by themselves. For one to blow you probably have a significant short for some reason. Any mods made or accidents in the cars history?Dave

[joatmon]

The things that still work are things that work when the car is off, the things that no longer work are the kinds of things that only work when you turn the key. That would lead me to consider either the ignition switch or the ignition relay. The ignition relay is one of three similar relays on top of the under dash fuse block. tribalman posted a parts id diagram of the top of that fus block in http://forums.genvibe.com/zerothread?id=39007 I'm pretty sure the ignition (IG1) relay is the same part as the P/W relay, so you could try just swapping the two to see if that helps Essiest to access by removing the little storage bin and/or the vent/mirror control trim piece

[the_sarge]

I found the AM1 fuse under the dash to be blown. It looked perfect, even under a magnifying glass. But it showed open with a multimeter. So it must have blown inside the plastic where the blades come in. I was sure I found the problem but...no.So then I swapped the two relays and the things that were dead worked! I slid down to Autozone and got a relay and now she's back on the road! The alternator now checks good as well. The old one did test bad out of the car. Lesson learned: you can't judge a fuse by how it looks. And once again GenVibers came through! THANK YOU!

[Sublimewind]

That's awesome man... And no, no you can't sometimes judge a fuse visually.. strange.. Relay.. good find..!!