diff --git a/src/main/java/net/wimpi/modbus/io/ModbusRTUTransport.java b/src/main/java/net/wimpi/modbus/io/ModbusRTUTransport.java
index 6bfadb6..4b74a43 100755
--- a/src/main/java/net/wimpi/modbus/io/ModbusRTUTransport.java
+++ b/src/main/java/net/wimpi/modbus/io/ModbusRTUTransport.java
@@ -311,7 +311,7 @@ private void getResponse(int fn, BytesOutputStream out) throws IOException {
             }
         } catch (IOException e) {
             m_CommPort.disableReceiveThreshold();
-            throw new IOException("getResponse serial port exception");
+            throw e;
         }
     }// getResponse
 
diff --git a/src/main/java/net/wimpi/modbus/io/ModbusTCPTransport.java b/src/main/java/net/wimpi/modbus/io/ModbusTCPTransport.java
index c43eef3..12e7453 100755
--- a/src/main/java/net/wimpi/modbus/io/ModbusTCPTransport.java
+++ b/src/main/java/net/wimpi/modbus/io/ModbusTCPTransport.java
@@ -176,7 +176,8 @@ public ModbusRequest readRequest() throws ModbusIOException {
             throw new ModbusIOException(true);
         } catch (Exception ex) {
             // ex.printStackTrace();
-            throw new ModbusIOException("I/O exception - failed to read.");
+            throw new ModbusIOException(String.format("I/O exception - failed to read: %s %s",
+                    ex.getClass().getSimpleName(), ex.getMessage()));
         }
     }// readRequest