diff --git a/hikaricp-java6/src/main/java/com/zaxxer/hikari/pool/HikariPool.java b/hikaricp-java6/src/main/java/com/zaxxer/hikari/pool/HikariPool.java
index b58160b7..364b6243 100644
--- a/hikaricp-java6/src/main/java/com/zaxxer/hikari/pool/HikariPool.java
+++ b/hikaricp-java6/src/main/java/com/zaxxer/hikari/pool/HikariPool.java
@@ -416,23 +416,20 @@ public final class HikariPool implements HikariPoolMBean, IBagStateListener
          connection = (username == null && password == null) ? dataSource.getConnection() : dataSource.getConnection(username, password);
 
          isUseNetworkTimeout = isJdbc41Compliant(connection) && (configuration.getConnectionTimeout() != Integer.MAX_VALUE);
-         isUseJdbc4Validation = isJdbc40Compliant(connection);
+         isUseJdbc4Validation = isJdbc40Compliant(connection) && configuration.getConnectionTestQuery() == null;
          if (!isUseJdbc4Validation && configuration.getConnectionTestQuery() == null) {
             LOGGER.error("JDBC4 Connection.isValid() method not supported, connection test query must be configured");
          }
-         isUseJdbc4Validation &= configuration.getConnectionTestQuery() == null;
 
          final boolean timeoutEnabled = (configuration.getConnectionTimeout() != Integer.MAX_VALUE);
          final long timeoutMs = timeoutEnabled ? Math.max(250L, configuration.getConnectionTimeout()) : 0L;
          final int originalTimeout = setNetworkTimeout(houseKeepingExecutorService, connection, timeoutMs, isUseNetworkTimeout);
 
          transactionIsolation = (transactionIsolation < 0 ? connection.getTransactionIsolation() : transactionIsolation);
+         
+         setupConnection(connection, isAutoCommit, isReadOnly, transactionIsolation, catalog);
          connectionCustomizer.customize(connection);
-
          executeSqlAutoCommit(connection, configuration.getConnectionInitSql());
-
-         setupConnection(connection, isAutoCommit, isReadOnly, transactionIsolation, catalog);
-
          setNetworkTimeout(houseKeepingExecutorService, connection, originalTimeout, isUseNetworkTimeout);
          
          connectionBag.add(new PoolBagEntry(connection, configuration.getMaxLifetime()));
diff --git a/hikaricp/src/main/java/com/zaxxer/hikari/pool/HikariPool.java b/hikaricp/src/main/java/com/zaxxer/hikari/pool/HikariPool.java
index 9295bce2..4982fb46 100644
--- a/hikaricp/src/main/java/com/zaxxer/hikari/pool/HikariPool.java
+++ b/hikaricp/src/main/java/com/zaxxer/hikari/pool/HikariPool.java
@@ -399,23 +399,20 @@ public final class HikariPool implements HikariPoolMBean, IBagStateListener
          connection = (username == null && password == null) ? dataSource.getConnection() : dataSource.getConnection(username, password);
 
          isUseNetworkTimeout = isJdbc41Compliant(connection) && (configuration.getConnectionTimeout() != Integer.MAX_VALUE);
-         isUseJdbc4Validation = isJdbc40Compliant(connection);
+         isUseJdbc4Validation = isJdbc40Compliant(connection) && configuration.getConnectionTestQuery() == null;
          if (!isUseJdbc4Validation && configuration.getConnectionTestQuery() == null) {
             LOGGER.error("JDBC4 Connection.isValid() method not supported, connection test query must be configured");
          }
-         isUseJdbc4Validation &= configuration.getConnectionTestQuery() == null;
 
          final boolean timeoutEnabled = (configuration.getConnectionTimeout() != Integer.MAX_VALUE);
          final long timeoutMs = timeoutEnabled ? Math.max(250L, configuration.getConnectionTimeout()) : 0L;
          final int originalTimeout = setNetworkTimeout(houseKeepingExecutorService, connection, timeoutMs, isUseNetworkTimeout);
 
          transactionIsolation = (transactionIsolation < 0 ? connection.getTransactionIsolation() : transactionIsolation);
+         
+         setupConnection(connection, isAutoCommit, isReadOnly, transactionIsolation, catalog);
          connectionCustomizer.customize(connection);
-
          executeSqlAutoCommit(connection, configuration.getConnectionInitSql());
-
-         setupConnection(connection, isAutoCommit, isReadOnly, transactionIsolation, catalog);
-
          setNetworkTimeout(houseKeepingExecutorService, connection, originalTimeout, isUseNetworkTimeout);
          
          connectionBag.add(new PoolBagEntry(connection, configuration.getMaxLifetime()));