diff --git a/serial/serbridge.c b/serial/serbridge.c
index e18ac82..0d6dc57 100644
--- a/serial/serbridge.c
+++ b/serial/serbridge.c
@@ -328,6 +328,8 @@ void ICACHE_FLASH_ATTR serbridgeInitPins() {
 	if (flashConfig.swap_uart) {
 		PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTCK_U, 4);
 		PIN_FUNC_SELECT(PERIPHS_IO_MUX_MTDO_U, 4);
+		PIN_PULLUP_DIS(PERIPHS_IO_MUX_MTCK_U);
+		PIN_PULLUP_DIS(PERIPHS_IO_MUX_MTDO_U);
 		system_uart_swap();
 	} else {
 		PIN_FUNC_SELECT(PERIPHS_IO_MUX_U0TXD_U, 0);