Oil pressure switch

[Bill Shaw]

Where's the oil pressure switch on a '99 A6QA 2.8L?  I'm getting an 
intermittent oil pressure warning on hard acceleration,  I'm thinking 
flaky electrical connection..  Oil level is fine, fresh new M1,  9 miles 
on the car since TB, WP, etc.  Just got it registered this morning.

BTW - ABS & brake lights went off the first time I used the brakes.  
Probably just rust scale near the sensors & it blew out.

Thanks,

Bill