diff --git a/test/py/tests/test_efi_capsule/conftest.py b/test/py/tests/test_efi_capsule/conftest.py
index 9160f294e60..dd41da9284e 100644
--- a/test/py/tests/test_efi_capsule/conftest.py
+++ b/test/py/tests/test_efi_capsule/conftest.py
@@ -51,21 +51,15 @@ def efi_capsule_data(request, u_boot_config):
             check_call('cp %s/capsule_pub_key_bad.crt %s/SIGNER2.crt'
                        % (key_dir, data_dir), shell=True)
 
-            # Update dtb adding capsule certificate
-            check_call('cd %s; '
-                       'cp %s/test/py/tests/test_efi_capsule/signature.dts .'
-                       % (data_dir, u_boot_config.source_dir), shell=True)
-            check_call('cd %s; '
-                       'dtc -@ -I dts -O dtb -o signature.dtbo signature.dts; '
-                       'fdtoverlay -i %s/arch/sandbox/dts/test.dtb '
-                            '-o test_sig.dtb signature.dtbo'
-                       % (data_dir, u_boot_config.build_dir), shell=True)
-
         # Update dtb to add the version information
         check_call('cd %s; '
                    'cp %s/test/py/tests/test_efi_capsule/version.dts .'
                    % (data_dir, u_boot_config.source_dir), shell=True)
+
         if capsule_auth_enabled:
+            check_call('cd %s; '
+                       'cp %s/arch/sandbox/dts/test.dtb test_sig.dtb'
+                       % (data_dir, u_boot_config.build_dir), shell=True)
             check_call('cd %s; '
                        'dtc -@ -I dts -O dtb -o version.dtbo version.dts; '
                        'fdtoverlay -i test_sig.dtb '
diff --git a/test/py/tests/test_efi_capsule/signature.dts b/test/py/tests/test_efi_capsule/signature.dts
deleted file mode 100644
index 078cfc76c93..00000000000
--- a/test/py/tests/test_efi_capsule/signature.dts
+++ /dev/null
@@ -1,10 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0+
-
-/dts-v1/;
-/plugin/;
-
-&{/} {
-	signature {
-		capsule-key = /incbin/("SIGNER.esl");
-	};
-};