I'm having the same problem. This is the logic I am using to analyze it:
1. If the light to the agitator unit also does not go on, there may be a power supply issue to the agitator motor/light. I tested this with a volt-meter, and discovered that there is no registered power to the lower unit.
2. I disassembled the upper unit, where the vacuum motor is, and found that there is power to the motor, and to a small black 'box' into which the power feeds [part no. V-16G-3625L made by Omron (the 2nd 6 could be a G... it's a little scratched)]. The power is live going in, but not coming out. This may be the issue. There is also a second small transitor board that receives from the first [part no. C49VAVG00000] It divides the power between the light/agitator motor and some other device in the agitator unit. It also showed no power. Thus
3. I will be taking the part number for these two boards to the appliance parts store (or perhaps Sears carries them) and if they are fairly inexpensive, try replacing them (very simple to do).
The net effect is that I may be saving myself another $300+ in vacuum cleaner costs... or I just learned how a vacuum cleaner works in case I ever need to study for a second job.
I'll let you know what I find out.
(I took pictures of the parts to show the appliance store, since I'm not sure what number on it is relevant.)
Ken, January 2008
