When i use my turn signals the high beams come on

Likely a bad ground, but could be a fuse(s), or a failed multifunction switch, or BCM. It requires circuit testing to identify the cause.

System Description INFOID:0000000009478426 Control of the headlamp system operation is dependent upon the position of the combination switch (lighting and turn signal switch). When the combination switch (lighting and turn signal switch) is placed in the 2nd position, the BCM (body control module) receives input requesting the headlamps and park lamps to illuminate. This input is communicated to the IPDM E/R (intelligent power distribution module engine room) via the CAN communication lines. The CPU (central processing unit) of the IPDM E/R controls the headlamp high and headlamp low relay coils. When energized, these relays direct power to the respective headlamps, which then illuminate. HIGH BEAM OPERATION/FLASH-TO-PASS OPERATION With the combination switch (lighting and turn signal switch) in the 2ND position and placed in HIGH position, the BCM receives input requesting the headlamp high beams to illuminate. The flash to pass feature can be used any time and also sends a signal to the BCM. This input is communicated to the IPDM E/R via the CAN communication lines. The CPU of the combination meter controls the ON/OFF status off the HIGH BEAM indicator. The CPU of the IPDM E/R controls the headlamp high relay coil which supplies power to the high beam headlamps. The combination meter receives a high beam request signal (ON) via the CAN communication lines and turns the high beam indicator lamp ON.
Relays are located in the underhood fuse relay box , look inside the lid for location #

Do you know anything about automotive electronics ? Electronic control modules .
Headlamp ON/OFF control is determined by the body control module (BCM) by a signal on the headlamp switch on input circuit when the headlamp switch is in the HEAD position. When the headlamp switch is in the AUTO position, the BCM determines headlamps ON/OFF by the voltage from the ambient light sensor.
If the headlight switch is left in the ON position, the inadvertent power control feature will turn OFF the headlights approximately 10 minutes after the ignition switch is turned to the OFF position. If the driver places the headlight switch in the ON position after the ignition switch has been turned OFF, or if the ignition switch is in the ACCY position, the headlights will remain ON until turned OFF or the battery runs dead.
The high beam indicator is illuminated when the instrument cluster receives a GMLAN serial data message from the BCM that the high beams are illuminated.
High Beams
The high beam headlamps receive voltage from the headlamp high relay located in the underhood fuse block. The BCM controls the relay on the headlamp high beam relay control circuit. High beam control is determined by a signal on the headlamp dimmer switch signal circuit from the multifunction switch. When the headlamp dimmer switch signal circuit is grounded, the BCM grounds the headlamp high beam relay control circuit, illuminating the high beam headlamps. The right and left high beam circuits are independent and are fused independently in the underhood fuse block.
Low Beams - Standard
The low beam headlamps receive voltage from the headlamp low beam relay located in the underhood fuse block. The BCM controls the relay on the headlamp low beam relay control circuit. Low beam control is determined by a signal on the headlamp dimmer switch signal circuit from the multifunction switch. When the headlamp dimmer switch signal circuit is open, the BCM grounds the headlamp low beam relay control circuit, illuminating the low beam headlamps. The right and left low beam circuits are independent are fused independently in the underhood fuse block.

Hooking up a factory scan tool an checking DTC'S - diagnostic trouble codes would be the very first step in trouble shooting this problem .
DTC B257A 00: Headlamp Switch Input Signal Mismatch
DTC 2575 00: Headlamp Control Circuit

Faulty switch.

Hello, is sounds like your issues are coming from within your turn signal/high-low beam switch. Most of the time the wires get worn or break and start rubbing around on each other causing troubles within the electrical circuit. Other times the contact switches inside the turn signal/high beam switch/lever wear and loose contact over time. You may be able to see wires leading from switch into steering colum. Check for bad wires, if none you may have to replace switch which you can get from any junkyard for bout 5 bucks plus learn how to take it apart in a junk car no one is worried about getting destroyed. BE CAREFULL WITH AIRBAGS when you pull your steering wheel to fix switch. It is not a difficult job to do.

high beams are turned on by pulling the turn signal arm towards steering wheel. pulling it ahead again will turn high beams off.

The multifunction switch may be the problem.

change the switch

pull on the signal lever toward you (ceter position). the signal lever controls the head lights either high beam or low beam. if you pull on the signal lever toward you again, you will have high beam temporarily. and if you push the signal lever towards the front, you will have the high beam locked.

there should be seperate fuses for the high beams in the under hood fuse box try checking them