Kia headlights and instrument cluster screwiness

I have a 2001 Kia Optima that is in surprisingly good condition for the 125,000 miles that are on it. A problem reared its ugly head yesterday, though. When I drove the highway to work, I noticed that my speedometer was telling me that I was apparently not moving at all. I thought it annoying, but continued on to work anyway. That evening, when I got off work, I found that the Headlights had ceased to function as well. My brights turned on, so I decided to simply drive home on those. I didn’t even make it out of the parking lot before THOSE flickered and went out, too. Thoroughly vexed, I hitched a ride home with my Father in Law and left the car until sunrise. As I drove it home, over hill and over dale, I found it odd that my tachometer was under the impression that the engine kept a steady 800 rpms the entire trip. I’ve checked every fuse I could think of and checked every lamp in my headlights and brights. What’s going on and how much will this cost me?

Have the alternator checked out. Check to see if there more than .25 volts of AC voltage across the battery with the engine running. If there is then the alternator is bad.

If the headlight bulbs aren’t burned out then check to see if a 10 amp fuse is ok located in a junction block. It may be under the hood but I’m not sure. The taillight relay is inside it also. The fuse supplies power to the headlight relay coils. If that fuse is ok then check the voltage getting to the coil. There may be a faulty connection somewhere to the coils. It would be good also to verify voltage is getting to the headlight fuses.

Checked it, and you were right. Bad regulator. I guess I’m lucky i got my last w2 today. I need to change the alternator, obviously, but what’s the best way to diagnose the headlight problem? I’d really appreciate any advise I can get.

You’re welcome for the help.

To check the headlights I recommend you use a test light probe and make sure power is getting to the fuse I mentioned earlier. If you have power there then I guess you should see if power is getting to the headlight relays and to the headlights.