No headlights only highbeam when the turn signal swtch pull back

Its supposed to do that.
You are using the "pass" option where you flash your bright lights to let someone know you are going to pass.
Depending on the make model and year, the problem could be the headlight switch or even the dimmer switch.

Well the turn signals are a different circuit.
Usually the common problem with one headlight is the ground circuit.
Both the high and low beam use the same ground. I would check for power for each circuit and a good ground at the light socket.

replace the high beam switch which causes this problem. Also clean the terminals for the directional light bulb. That will cause a negative continuity to the bulb

I don't know what make of vehical you have but on most cars you pull the lever back to flash someone and push it forword to turn on to turn on the highbeams. Just a idea.

Yes, the low beams will shut off if you turn on high beam. Not sure which way yours work but if you push the lever for high beam, pull the lever back and all lights will come on or vise versa. You would think all the lights would turn on when going into high beam.

PROBLEM COULD BE A FAULTY TURN SIGNAL COMBINATION SWITCH.

replace the main headlight switch and the connector to that switch, the connector can be obtained from the dealer only in most cases.

If you were flashing your high beams to get the car in front of you out of the way then maybe it is just karma.

First off, do you have a knob on the dash for the headlights, or do you have a lever on the column that turns them on? If you have the lever on the column, and you can turn on the highbeams by pulling back on the turn signal stalk, and hitting the hazard button turns the flashers on, then chances are the stalk is bad (it's called the combination switch and it's a common failure on the B5 chassis cars (the Passat and Audi A4)).

Try that out - hit the hazard button and see if the hazards work. Pull back on the stalk and see if the high beams come on (they should - toggling like that uses a circuit that is separate from the usual headlight circuits).

Post back up with the results of these checks:

Headlight switch on column or dash?
Highbeams turn on when turn signal stalk is pulled back?
Hazard button activates hazard lights?

Let me know what you find out and I'll be able to tell you more definitely.

look at your lo beam relay. Lo beam and Hi beamlights are on seperate relays