diff --git a/src/ophyd_async/core/mock_signal_utils.py b/src/ophyd_async/core/mock_signal_utils.py
index 6a79709684..38e23a6c99 100644
--- a/src/ophyd_async/core/mock_signal_utils.py
+++ b/src/ophyd_async/core/mock_signal_utils.py
@@ -1,5 +1,5 @@
 from contextlib import asynccontextmanager, contextmanager
-from typing import Any, Callable, Iterable, Iterator, List
+from typing import Any, Callable, Iterable
 from unittest.mock import ANY, Mock
 
 from ophyd_async.core.signal import Signal
@@ -22,7 +22,7 @@ def set_mock_value(signal: Signal[T], value: T):
     backend.set_value(value)
 
 
-def set_mock_put_proceeds(signal: Signal[T], proceeds: bool):
+def set_mock_put_proceeds(signal: Signal, proceeds: bool):
     """Allow or block a put with wait=True from proceeding"""
     backend = _get_mock_signal_backend(signal)
 
@@ -33,7 +33,7 @@ def set_mock_put_proceeds(signal: Signal[T], proceeds: bool):
 
 
 @asynccontextmanager
-async def mock_puts_blocked(*signals: List[Signal]):
+async def mock_puts_blocked(*signals: Signal):
     for signal in signals:
         set_mock_put_proceeds(signal, False)
     yield
@@ -79,7 +79,7 @@ def __next__(self):
         return next_value
 
     def __del__(self):
-        if self.require_all_consumed and self.index != len(self.values):
+        if self.require_all_consumed and self.index != len(list(self.values)):
             raise AssertionError("Not all values have been consumed.")
 
 
@@ -87,7 +87,7 @@ def set_mock_values(
     signal: Signal,
     values: Iterable[Any],
     require_all_consumed: bool = False,
-) -> Iterator[Any]:
+) -> _SetValuesIterator:
     """Iterator to set a signal to a sequence of values, optionally repeating the
     sequence.
 
@@ -127,7 +127,7 @@ def _unset_side_effect_cm(put_mock: Mock):
     put_mock.side_effect = None
 
 
-def callback_on_mock_put(signal: Signal, callback: Callable[[T], None]):
+def callback_on_mock_put(signal: Signal[T], callback: Callable[[T], None]):
     """For setting a callback when a backend is put to.
 
     Can either be used in a context, with the callback being
diff --git a/tests/core/test_mock_signal_backend.py b/tests/core/test_mock_signal_backend.py
index 7b16431e91..2cce6dff7e 100644
--- a/tests/core/test_mock_signal_backend.py
+++ b/tests/core/test_mock_signal_backend.py
@@ -31,6 +31,7 @@ async def test_mock_signal_backend(connect_mock_mode):
     # If mock is false it will be handled like a normal signal, otherwise it will
     # initalize a new backend from the one in the line above
     await mock_signal.connect(mock=connect_mock_mode)
+    assert isinstance(mock_signal._backend, MockSignalBackend)
 
     assert await mock_signal._backend.get_value() == ""
     await mock_signal._backend.put("test")
@@ -74,6 +75,8 @@ async def test_set_mock_put_proceeds():
     mock_signal = SignalW(SoftSignalBackend(str))
     await mock_signal.connect(mock=True)
 
+    assert isinstance(mock_signal._backend, MockSignalBackend)
+
     assert mock_signal._backend.put_proceeds.is_set() is True
 
     set_mock_put_proceeds(mock_signal, False)
@@ -95,6 +98,7 @@ async def test_set_mock_put_proceeds_timeout():
 async def test_put_proceeds_timeout():
     mock_signal = SignalW(SoftSignalBackend(str))
     await mock_signal.connect(mock=True)
+    assert isinstance(mock_signal._backend, MockSignalBackend)
 
     assert mock_signal._backend.put_proceeds.is_set() is True
 
@@ -115,11 +119,11 @@ async def test_mock_utils_throw_error_if_backend_isnt_mock_signal_backend():
         assert_mock_put_called_with(signal, 10)
     exc_msgs.append(str(exc.value))
     with pytest.raises(AssertionError) as exc:
-        async with mock_puts_blocked(signal, 10):
+        async with mock_puts_blocked(signal):
             ...
     exc_msgs.append(str(exc.value))
     with pytest.raises(AssertionError) as exc:
-        with callback_on_mock_put(signal, 10):
+        with callback_on_mock_put(signal, lambda x: _):
             ...
     exc_msgs.append(str(exc.value))
     with pytest.raises(AssertionError) as exc:
@@ -216,10 +220,8 @@ async def test_callback_on_mock_put_no_ctx():
     mock_signal = SignalRW(SoftSignalBackend(float))
     await mock_signal.connect(mock=True)
     calls = []
-    (
-        callback_on_mock_put(
-            mock_signal, lambda *args, **kwargs: calls.append({**kwargs, "_args": args})
-        ),
+    callback_on_mock_put(
+        mock_signal, lambda *args, **kwargs: calls.append({**kwargs, "_args": args})
     )
     await mock_signal.set(10.0)
     assert calls == [
@@ -249,16 +251,16 @@ def some_function_without_kwargs(arg):
 async def test_set_mock_values(mock_signals):
     signal1, signal2 = mock_signals
 
-    await signal2.get_value() == "first_value"
+    assert await signal2.get_value() == "first_value"
     for value_set in set_mock_values(signal1, ["second_value", "third_value"]):
         assert await signal1.get_value() == value_set
 
     iterator = set_mock_values(signal2, ["second_value", "third_value"])
-    await signal2.get_value() == "first_value"
+    assert await signal2.get_value() == "first_value"
     next(iterator)
-    await signal2.get_value() == "second_value"
+    assert await signal2.get_value() == "second_value"
     next(iterator)
-    await signal2.get_value() == "third_value"
+    assert await signal2.get_value() == "third_value"
 
 
 async def test_set_mock_values_exhausted_passes(mock_signals):