diff --git a/vllm/disaggregated/disagg_worker.py b/vllm/disaggregated/disagg_worker.py
index 322ce9e07892..206bc9bacbeb 100644
--- a/vllm/disaggregated/disagg_worker.py
+++ b/vllm/disaggregated/disagg_worker.py
@@ -96,9 +96,17 @@ async def _abort_handler(self, req: GenerationRequest):
         self.engine.abort(request_id=req.request_id)
 
     async def _heartbeat_handler(self, req: HeartbeatRequest):
+        try:
+            self.engine.check_health()
+            status = "OK"
+        except Exception:
+            status = "FAIL"
+            logger.exception("Check health Failed.")
+
         msg = (ResponseType.HEARTBEAT,
                self.encoder.encode(
-                   HeartbeatResponse(request_id=req.request_id, status="OK")))
+                   HeartbeatResponse(request_id=req.request_id,
+                                     status=status)))
         await self.to_proxy.send_multipart(msg, copy=False)
 
     async def _generate(
diff --git a/vllm/disaggregated/proxy.py b/vllm/disaggregated/proxy.py
index 5d77c04bb359..d6c96c6ddd8f 100644
--- a/vllm/disaggregated/proxy.py
+++ b/vllm/disaggregated/proxy.py
@@ -53,6 +53,12 @@ def __init__(
         health_check_interval=10,
         health_threshold=3,
     ):
+        self._check_type("enable_health_monitor", enable_health_monitor, bool)
+        self._check_positive_int("health_check_interval",
+                                 health_check_interval)
+        self._check_positive_int("health_threshold", health_threshold)
+        self._check_subclass("router", router, RoutingInterface)
+
         self.queues: dict[str, asyncio.Queue] = {}
 
         self.encoder = msgspec.msgpack.Encoder()
@@ -498,6 +504,20 @@ async def get_vllm_config(self) -> VllmConfig:
     async def reset_mm_cache(self) -> None:
         raise NotImplementedError
 
+    def _check_type(self, name, value, expected_type):
+        if not isinstance(value, expected_type):
+            raise TypeError(f"{name} must be {expected_type.__name__}, ",
+                            f"got {type(value).__name__}")
+
+    def _check_positive_int(self, name, value):
+        if not isinstance(value, int) or value <= 0:
+            raise ValueError(f"{name} must be a positive integer")
+
+    def _check_subclass(self, name, value, base_class):
+        if not isinstance(value, type) or not issubclass(value, base_class):
+            raise TypeError(
+                f"{name} must be a subclass of {base_class.__name__}")
+
 
 def _has_mm_data(prompt: PromptType) -> bool:
     if isinstance(prompt, dict):
diff --git a/vllm/v1/engine/async_llm.py b/vllm/v1/engine/async_llm.py
index 7fb36cf5941e..198c3a474344 100644
--- a/vllm/v1/engine/async_llm.py
+++ b/vllm/v1/engine/async_llm.py
@@ -486,6 +486,8 @@ async def do_log_stats(
 
     async def check_health(self) -> None:
         logger.debug("Called check_health.")
+        if self.errored:
+            raise self.dead_error
 
     async def start_profile(self) -> None:
         await self.engine_core.profile_async(True)