diff --git a/CHANGELOG.md b/CHANGELOG.md
index 00bd7c84b0fb9..a014b6a2cab72 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -252,6 +252,10 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 - Changed `HorovodPlugin.all_gather` to return a `torch.Tensor` instead of a list ([#9696](https://github.com/PyTorchLightning/pytorch-lightning/pull/9696))
 
 
+- Changed Trainer connectors to be protected attributes:
+    * Configuration Validator ([#9779](https://github.com/PyTorchLightning/pytorch-lightning/pull/9779))
+
+
 - Restore `current_epoch` and `global_step` irrespective of trainer task ([#9413](https://github.com/PyTorchLightning/pytorch-lightning/pull/9413))
 
 
diff --git a/pytorch_lightning/trainer/trainer.py b/pytorch_lightning/trainer/trainer.py
index af225e708e343..a33462defb3c7 100644
--- a/pytorch_lightning/trainer/trainer.py
+++ b/pytorch_lightning/trainer/trainer.py
@@ -391,7 +391,7 @@ def __init__(
         gpu_ids, tpu_cores = self._parse_devices(gpus, auto_select_gpus, tpu_cores)
 
         # init connectors
-        self.config_validator = ConfigValidator(self)
+        self._config_validator = ConfigValidator(self)
         self.data_connector = DataConnector(self, multiple_trainloader_mode)
         self.optimizer_connector = OptimizerConnector(self)
 
@@ -978,7 +978,7 @@ def _run(self, model: "pl.LightningModule") -> Optional[Union[_EVALUATE_OUTPUT,
         if hasattr(model, "hparams"):
             parsing.clean_namespace(model.hparams)
 
-        self.config_validator.verify_loop_configurations(model)
+        self._config_validator.verify_loop_configurations(model)
 
         # attach model log function to callback
         self.callback_connector.attach_model_logging_functions(model)