diff --git a/tests/bluetooth/bsim_bt/bsim_test_app/tests_scripts/basic_conn.sh b/tests/bluetooth/bsim_bt/bsim_test_app/tests_scripts/basic_conn.sh
index a1dd1cfca0a..8df2d8c936f 100755
--- a/tests/bluetooth/bsim_bt/bsim_test_app/tests_scripts/basic_conn.sh
+++ b/tests/bluetooth/bsim_bt/bsim_test_app/tests_scripts/basic_conn.sh
@@ -4,9 +4,9 @@
 
 # Basic connection test: a central connects to a peripheral and expects a
 # notification
-SIMULATION_ID="basic_conn"
-VERBOSITY_LEVEL=2
-PROCESS_IDS=""; EXIT_CODE=0
+simulation_id="basic_conn"
+verbosity_level=2
+process_ids=""; exit_code=0
 
 function Execute(){
   if [ ! -f $1 ]; then
@@ -14,7 +14,7 @@ function Execute(){
  compile it?)\e[39m"
     exit 1
   fi
-  timeout 5 $@ & PROCESS_IDS="$PROCESS_IDS $!"
+  timeout 5 $@ & process_ids="$process_ids $!"
 }
 
 : "${BSIM_OUT_PATH:?BSIM_OUT_PATH must be defined}"
@@ -25,17 +25,17 @@ BOARD="${BOARD:-nrf52_bsim}"
 cd ${BSIM_OUT_PATH}/bin
 
 Execute ./bs_${BOARD}_tests_bluetooth_bsim_bt_bsim_test_app_prj_conf \
-  -v=${VERBOSITY_LEVEL} -s=${SIMULATION_ID} -d=0 -RealEncryption=0 \
+  -v=${verbosity_level} -s=${simulation_id} -d=0 -RealEncryption=0 \
   -testid=peripheral -rs=23
 
 Execute ./bs_${BOARD}_tests_bluetooth_bsim_bt_bsim_test_app_prj_conf \
-  -v=${VERBOSITY_LEVEL} -s=${SIMULATION_ID} -d=1 -RealEncryption=0 \
+  -v=${verbosity_level} -s=${simulation_id} -d=1 -RealEncryption=0 \
   -testid=central -rs=6
 
-Execute ./bs_2G4_phy_v1 -v=${VERBOSITY_LEVEL} -s=${SIMULATION_ID} \
+Execute ./bs_2G4_phy_v1 -v=${verbosity_level} -s=${simulation_id} \
   -D=2 -sim_length=20e6 $@
 
-for PROCESS_ID in $PROCESS_IDS; do
-  wait $PROCESS_ID || let "EXIT_CODE=$?"
+for process_id in $process_ids; do
+  wait $process_id || let "exit_code=$?"
 done
-exit $EXIT_CODE #the last exit code != 0
+exit $exit_code #the last exit code != 0