Audi Repair: Reverse lights do not work, wire sensor, magnetic sensor

Question
QUESTION: I have an audi a6 automatic shifter, 2.8 v6 1995 (c4), when the shifter is in reverse position the electrical lights switch do not works. How to locate this switch? does it in inside the shifter box or not ?

ANSWER: The switch is usually accessible from the outside of the transmission.  Normally something happens to the connection, but sometimes the switch itself goes bad.  Look for a single wire connector on the outside of the transmission.  Jan

---------- FOLLOW-UP ----------

QUESTION: Hi,thank you for your answer. But looking at the gear  
box, I can see the multi-wire connector and another mono-wired
connector that is very near the axle that seams to be an electro-magnetic sensor. The car, motor end gear models are:4A20R8 / AAH / CYR  
AAH /

Answer
The electrom magnetic sensor is probably the speed sensor, if it is located near the final drive.  Check for another single wire sensor, normally these are replaceable seperately.  Possibly they included this in the multi-wire plug but I don't thinks so.  Clean the terminals on the multi-plug anyway and see if that fixes it.  Let me know what you find,  Jan