Toyota Repair: Headlight issues on a 99 Camry,, haynes manual, fuse panel

Question
This car has been having progressively worsening headlight issues. At first the headlights would not come on, wiggling the relay under the hood would render them on. The backlights and parking lights had no issues. The next step was the headlights coming on but only in DRL mode, no full lights. When I pull on the switch for "Flash" or high beam the blue indicator in the dash comes on but no change. The interior dash and console lights come when I put on the parking lights. Now I have no lights whatsoever, including the tailights and parking lights. There is power to the headlight relay even with the car/lights off but no power to the respective headlight fuses. The relay will click once inserted to indicate connection and an ammeter showed about 11-13volts supply. Could it be the fusebox with gremlins? I took out the headlight switch and measured for continuity according to Haynes Manual and all seemed well. All fuses and fusible links look to be in order. Directional and hazards are working fine. What could be causing power to the relay even with the car off, or is this the way they are designed? I am not very familiar with the Camry. All help appreciated in advance.
The car is an auto, 123K miles with daytime driving lights.

Answer
Without actually being able to do some basic testing myself it's a little difficult to diagnose an electrical problem such as this but I can tell you that weird electrical problems like this can be caused by corroded or loose ground connections, some of them are located behind the kick panels and some are inside the dash, there are a lot of them, another reason that may cause this is the integration relay which is part of the body ecu, which controls just about everything as far as the body electrical system is concerned, we have seen this happen a few times, the body ecu is part of the fuse panel on the lower left side of the dash, this part is expensive, I'm not saying it should be replaced I'm just saying that it's a good possibility if the rest of the system is OK.