diff --git a/pt100/pt100.tex b/pt100/pt100.tex
index a080e92..b875bf8 100644
--- a/pt100/pt100.tex
+++ b/pt100/pt100.tex
@@ -648,7 +648,7 @@ $$ NoOfTestCasesToCheck = \frac{6!}{1!(6-1)!} + \frac{6!}{2!(6-2)!} - \Big( \fra
 $$ NoOfTestCasesToCheck = 6 + 15 - ( 1 + 1 + 1 )  = 18 $$
 
 As the test case are all different and are of the correct cardinalities (6 single faults and (15-3) double)
-we can be confident that we have looked at all combinations up to two, of the possible faults
+we can be confident that we have looked at all `double combinations', of the possible faults
 in the pt100 circuit. The next task is to investigate
 these test cases in more detail to prove the failure mode hypothese set out in table \ref{tab:ptfmea2}.
 
@@ -656,7 +656,7 @@ these test cases in more detail to prove the failure mode hypothese set out in t
 \subsection{Proof of Double Faults Hypothese }
 
 \subsubsection{ TC 7 : Voltages $R_1$ OPEN $R_2$ OPEN } 
-
+\label{pt100:bothfloating}
 This double fault mode produces an interesting symptom.
 Both sense lines are floating.
 We cannot know what the {\adctw} readings on them will be.
@@ -702,5 +702,50 @@ Both values will be out of range.
 
 
 
+
+\subsubsection{ TC 13 : Voltages $R_1$ SHORT $R_3$ OPEN }
+
+This shorts the sense+ to Vcc and the sense- to ground.
+Both values will be out of range.
+
+\subsubsection{ TC 14 : Voltages $R_1$ SHORT $R_3$ SHORT }
+
+This shorts the sense+ and sense- to Vcc.
+Both values will be out of range.
+
+\subsubsection{ TC 15 : Voltages $R_2$ OPEN $R_3$ OPEN }
+
+This shorts the sense+ to Vcc and causes sense- to float.
+The sense+ value will be out of range.
+
+
+\subsubsection{ TC 16 : Voltages $R_2$ OPEN $R_3$ SHORT }
+
+This shorts the sense+ and sense- to Vcc.
+Both values will be out of range.
+
+
+
+
+
+\subsubsection{ TC 17 : Voltages $R_2$ SHORT $R_3$ OPEN }
+
+This shorts the sense- to Ground.
+The sense- value will be out of range.
+
+
+\subsubsection{ TC 18 : Voltages $R_2$ SHORT $R_3$ SHORT }
+
+This shorts the sense+ and sense- to Vcc.
+Both values will be out of range.
+
+
+
+
+
+
+
+\vspace{20pt}
+
 typeset in {\Huge \LaTeX} \today