diff --git a/trunner/harness/plo.py b/trunner/harness/plo.py
index befb2384..4b73c9e4 100644
--- a/trunner/harness/plo.py
+++ b/trunner/harness/plo.py
@@ -285,6 +285,11 @@ def __call__(self):
 
         self.rebooter(flash=False, hard=True)
 
+        try:
+            self.dut.expect_exact(f"(psh)%", timeout=10)
+        except pexpect.TIMEOUT as e:
+            raise PloError("Error: missing psh prompt after flash!", output=self.dut.before) from e
+
 
 class PloPhoenixdAppLoader(TerminalHarness, PloInterface):
     """Harness to load the binaries to syspage using plo bootloader.