tests/src/Functional/ResourceTestBase.php | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/tests/src/Functional/ResourceTestBase.php b/tests/src/Functional/ResourceTestBase.php
index d897d67..9ef71a2 100644
--- a/tests/src/Functional/ResourceTestBase.php
+++ b/tests/src/Functional/ResourceTestBase.php
@@ -1933,7 +1933,8 @@ abstract class ResourceTestBase extends BrowserTestBase {
 
     // DX: 415 when request body in existing but not allowed format.
     $response = $this->request('POST', $url, $request_options);
-    $this->assertResourceErrorResponse(415, 'No route found that matches "Content-Type: text/xml"', $url, $response);
+    $this->assertSame(415, $response->getStatusCode());
+    $this->assertSame('text/html; charset=UTF-8', $response->getHeader('Content-Type')[0]);
 
     $request_options[RequestOptions::HEADERS]['Content-Type'] = 'application/vnd.api+json';