diff --git a/src/de/schildbach/pte/AbstractEfaProvider.java b/src/de/schildbach/pte/AbstractEfaProvider.java
index a1148f92..e233df52 100644
--- a/src/de/schildbach/pte/AbstractEfaProvider.java
+++ b/src/de/schildbach/pte/AbstractEfaProvider.java
@@ -1267,6 +1267,8 @@ public abstract class AbstractEfaProvider implements NetworkProvider
 
 	public int[] lineColors(final String line)
 	{
+		if (line.isEmpty())
+			return null;
 		return LINES.get(line.charAt(0));
 	}
 
diff --git a/src/de/schildbach/pte/AbstractHafasProvider.java b/src/de/schildbach/pte/AbstractHafasProvider.java
index 0d285f71..96f520c6 100644
--- a/src/de/schildbach/pte/AbstractHafasProvider.java
+++ b/src/de/schildbach/pte/AbstractHafasProvider.java
@@ -921,6 +921,8 @@ public abstract class AbstractHafasProvider implements NetworkProvider
 
 	public final int[] lineColors(final String line)
 	{
+		if (line.isEmpty())
+			return null;
 		return LINES.get(line.charAt(0));
 	}
 
diff --git a/src/de/schildbach/pte/BvgProvider.java b/src/de/schildbach/pte/BvgProvider.java
index 52d398be..b696df2c 100644
--- a/src/de/schildbach/pte/BvgProvider.java
+++ b/src/de/schildbach/pte/BvgProvider.java
@@ -746,6 +746,8 @@ public final class BvgProvider implements NetworkProvider
 
 	public int[] lineColors(final String line)
 	{
+		if (line.isEmpty())
+			return null;
 		return LINES.get(line);
 	}
 }