diff --git a/server/cluster/cluster.go b/server/cluster/cluster.go
index f8677ce98cb..a8bea953227 100644
--- a/server/cluster/cluster.go
+++ b/server/cluster/cluster.go
@@ -401,32 +401,52 @@ func (c *RaftCluster) checkSchedulingService() {
 // checkTSOService checks the TSO service.
 func (c *RaftCluster) checkTSOService() {
 	if !c.opt.GetMicroServiceConfig().IsTSODynamicSwitchingEnabled() {
-		if err := c.startTSOJobsIfNeeded(); err != nil {
+		if err := c.switchToInternalTSO(); err != nil {
 			log.Error("failed to start TSO jobs", errs.ZapError(err))
 			return
 		}
-		if c.IsServiceIndependent(constant.TSOServiceName) {
-			c.UnsetServiceIndependent(constant.TSOServiceName)
-		}
 		return
 	}
 
 	servers, err := discovery.Discover(c.etcdClient, constant.TSOServiceName)
-	if err != nil || len(servers) == 0 {
-		if err := c.startTSOJobsIfNeeded(); err != nil {
-			log.Error("failed to start TSO jobs", errs.ZapError(err))
+	if err != nil {
+		log.Error("failed to discover TSO service", errs.ZapError(err))
+		return
+	}
+
+	currentIsExternal := c.IsServiceIndependent(constant.TSOServiceName)
+	needSwitch := (len(servers) == 0) == currentIsExternal
+
+	if !needSwitch {
+		return
+	}
+
+	if len(servers) == 0 {
+		if err := c.switchToInternalTSO(); err != nil {
+			log.Error("failed to switch to internal TSO", errs.ZapError(err))
 			return
 		}
-		if c.IsServiceIndependent(constant.TSOServiceName) {
-			log.Info("TSO is provided by PD")
-			c.UnsetServiceIndependent(constant.TSOServiceName)
-		}
 	} else {
-		c.stopTSOJobsIfNeeded()
-		if !c.IsServiceIndependent(constant.TSOServiceName) {
-			log.Info("TSO is provided by TSO server")
-			c.SetServiceIndependent(constant.TSOServiceName)
-		}
+		c.switchToExternalTSO()
+	}
+}
+
+func (c *RaftCluster) switchToInternalTSO() error {
+	if err := c.startTSOJobsIfNeeded(); err != nil {
+		return err
+	}
+	if c.IsServiceIndependent(constant.TSOServiceName) {
+		c.UnsetServiceIndependent(constant.TSOServiceName)
+		log.Info("successfully switched to internal TSO")
+	}
+	return nil
+}
+
+func (c *RaftCluster) switchToExternalTSO() {
+	c.stopTSOJobsIfNeeded()
+	if !c.IsServiceIndependent(constant.TSOServiceName) {
+		c.SetServiceIndependent(constant.TSOServiceName)
+		log.Info("successfully switched to external TSO")
 	}
 }