diff --git a/lib/obp60task/PageAutobahn.cpp b/lib/obp60task/PageAutobahn.cpp
index bb3f36af..18c4b729 100644
--- a/lib/obp60task/PageAutobahn.cpp
+++ b/lib/obp60task/PageAutobahn.cpp
@@ -46,7 +46,7 @@ class PageAutobahn : public Page{
            // draw outline
            getdisplay().drawLine(x0, y0, x1, y1, color);
            getdisplay().drawLine(x1, y1, x2, y2, color);
-             getdisplay().drawLine(x2, y2, x3, y3, color);
+           getdisplay().drawLine(x2, y2, x3, y3, color);
            getdisplay().drawLine(x3, y3, x0, y0, color);
        }
     }
@@ -69,7 +69,7 @@ class PageAutobahn : public Page{
         String backlightMode = config->getString(config->backlight);
 
         String trackStep = config->getString(config->trackStep);
-        double seg_deg = trackStep.toFloat(); // degrees per display segment
+        double seg_step = trackStep.toFloat() * PI / 180;
 
         // Optical warning by limit violation (unused)
         if(String(flashLED) == "Limit Violation"){
@@ -136,20 +136,26 @@ class PageAutobahn : public Page{
         getdisplay().setCursor(360-w, 257);
         getdisplay().print(sval_btw);
 
+        bool valid = bv_cog->valid && bv_btw->valid;
+
         // autobahn view
 
         // draw ship symbol (as bitmap)
         getdisplay().drawXBitmap(184, 68, ship_bits, ship_width, ship_height, pixelcolor);
 
         // draw next waypoint name
-        String sval_wpname = "Tonne 122";
+        String sval_wpname = "no data";
+
+        if (valid) {
+			sval_wpname = "Tonne 122";
+        }
+
         getdisplay().setFont(&Ubuntu_Bold10pt7b);
         getdisplay().getTextBounds(sval_wpname, 0, 150, &x, &y, &w, &h);
         // TODO if text don't fix use smaller font size.
         // if smallest size does not fit use 2 lines
         // last resort: clip with ellipsis
         getdisplay().setCursor(200 - w / 2, 60);
-
         getdisplay().print(sval_wpname);
 
         // draw course segments
@@ -161,21 +167,26 @@ class PageAutobahn : public Page{
             diff -= 360;
         }
 
-        // default all segments activated
-        bool seg[6] = {true, true, true, true, true, true};
+        // as default all segments activated if valid calculation
+        // values are available
+        bool seg[6]; // segment layout: [2][1][0] | [3][4][5]
+        for (int i=0; i<6; i++) {
+            seg[i] = valid;
+        }
+
         // number of inactive segments
-        int nseg = std::min(static_cast<int>(std::floor(std::abs(diff) / seg_deg)), 5);
+        int nseg = std::min(static_cast<int>(std::floor(std::abs(diff) / seg_step)), 5);
 
         int order[6];
-        if (diff < 0) {
+        if (diff > 0) {
             // right
-            order[0] = 6; order[1] = 5; order[2] = 4;
-            order[3] = 1; order[4] = 2; order[5] = 3;
-        }    
-        else if (diff > 0) {
+            order[0] = 3; order[1] = 4; order[2] = 5;
+            order[3] = 0; order[4] = 1; order[5] = 2;
+        }
+        else if (diff < 0) {
             // left
-            order[0] = 3; order[1] = 2; order[2] = 1;
-            order[3] = 4; order[4] = 5; order[5] = 6;
+            order[0] = 0; order[1] = 1; order[2] = 2;
+            order[3] = 3; order[4] = 4; order[5] = 5;
         }
         int i = 0;
         while (nseg > 0) {
@@ -185,13 +196,13 @@ class PageAutobahn : public Page{
         }
 
         // left segments
-        drawSegment(0, 54, 46, 24, 75, 24, 0, 90, pixelcolor, seg[0]);
+        drawSegment(0, 54, 46, 24, 75, 24, 0, 90, pixelcolor, seg[2]);
         drawSegment(0, 100, 82, 24, 112, 24, 50, 100, pixelcolor, seg[1]);
-        drawSegment(60, 100, 117, 24, 147, 24, 110, 100, pixelcolor,seg[2]);
+        drawSegment(60, 100, 117, 24, 147, 24, 110, 100, pixelcolor,seg[0]);
         // right segments
-        drawSegment(399, 54, 354, 24, 325, 24, 399, 90, pixelcolor, seg[3]);
+        drawSegment(340, 100, 283, 24, 253, 24, 290, 100, pixelcolor, seg[3]);
         drawSegment(399, 100, 318, 24, 289, 24, 350, 100, pixelcolor, seg[4]);
-        drawSegment(340, 100, 283, 24, 253, 24, 290, 100, pixelcolor, seg[5]);
+        drawSegment(399, 54, 354, 24, 325, 24, 399, 90, pixelcolor, seg[5]);
 
         // Key Layout
         getdisplay().setFont(&Ubuntu_Bold8pt7b);
diff --git a/lib/obp60task/PageVoltage.cpp b/lib/obp60task/PageVoltage.cpp
index 77af4ca9..cc1f9bba 100644
--- a/lib/obp60task/PageVoltage.cpp
+++ b/lib/obp60task/PageVoltage.cpp
@@ -127,7 +127,7 @@ double raw = 0;
         }
         
         // Logging voltage value
-        if (raw == NULL) return;
+        if (raw == 0) return;
         LOG_DEBUG(GwLog::LOG,"Drawing at PageVoltage, Type:%s %s:=%f", batType, name1.c_str(), raw);
 
         // Draw page
diff --git a/lib/obp60task/RTClib.cpp b/lib/obp60task/RTClib.cpp
index 8c5429c1..ebc989fe 100644
--- a/lib/obp60task/RTClib.cpp
+++ b/lib/obp60task/RTClib.cpp
@@ -486,7 +486,7 @@ uint8_t RTC_BQ32000::readRegister(uint8_t address) {
     return Wire.read();
 }
 
-uint8_t RTC_BQ32000::writeRegister(uint8_t address, uint8_t value) {
+void RTC_BQ32000::writeRegister(uint8_t address, uint8_t value) {
     /* Write the given value to the register at the given address.
      */
     Wire.beginTransmission(BQ32000_ADDRESS);
@@ -513,4 +513,4 @@ DateTime RTC_Millis::now() {
     return offset + millis() / 1000;
 }
 
-////////////////////////////////////////////////////////////////////////////////
\ No newline at end of file
+////////////////////////////////////////////////////////////////////////////////
diff --git a/lib/obp60task/RTClib.h b/lib/obp60task/RTClib.h
index a99e791f..137c51fd 100644
--- a/lib/obp60task/RTClib.h
+++ b/lib/obp60task/RTClib.h
@@ -182,7 +182,7 @@ class RTC_BQ32000 {
 
     // utility functions:
     static uint8_t readRegister(uint8_t address);
-    static uint8_t writeRegister(uint8_t address, uint8_t value);
+    static void writeRegister(uint8_t address, uint8_t value);
     static uint8_t bcd2bin (uint8_t val) { return val - 6 * (val >> 4); }
     static uint8_t bin2bcd (uint8_t val) { return val + 6 * (val / 10); }
 };