diff --git a/poincare/test/parsing.cpp b/poincare/test/parsing.cpp
index c40c05c99..a0437eaf0 100644
--- a/poincare/test/parsing.cpp
+++ b/poincare/test/parsing.cpp
@@ -294,9 +294,11 @@ QUIZ_CASE(poincare_parsing_units) {
       Expression unit = parse_expression(buffer, nullptr, false);
       quiz_assert_print_if_failure(unit.type() == ExpressionNode::Type::Unit, "Should be parsed as a Unit");
       if (rep->isPrefixable()) {
-        size_t numberOfPrefixes = sizeof(Unit::AllPrefixes)/sizeof(Unit::Prefix *);
+        /* ton is only prefixable by positive prefixes */
+        bool isTon = strcmp("t", rep->rootSymbol()) == 0;
+        size_t numberOfPrefixes = ((isTon) ? sizeof(Unit::PositiveLongScalePrefixes) : sizeof(Unit::AllPrefixes))/sizeof(Unit::Prefix *);
         for (size_t i = 0; i < numberOfPrefixes; i++) {
-          const Unit::Prefix * pre = Unit::AllPrefixes[i];
+          const Unit::Prefix * pre = (isTon) ? Unit::PositiveLongScalePrefixes[i] : Unit::AllPrefixes[i];
           Unit::Builder(dim, rep, pre).serialize(buffer, bufferSize, Preferences::PrintFloatMode::Decimal, Preferences::VeryShortNumberOfSignificantDigits);
           Expression unit = parse_expression(buffer, nullptr, false);
           quiz_assert_print_if_failure(unit.type() == ExpressionNode::Type::Unit, "Should be parsed as a Unit");
diff --git a/poincare/test/simplification.cpp b/poincare/test/simplification.cpp
index 5a7bfd3d5..702fc6665 100644
--- a/poincare/test/simplification.cpp
+++ b/poincare/test/simplification.cpp
@@ -271,13 +271,13 @@ QUIZ_CASE(poincare_simplification_units) {
    *    t, Hz, S, ha, L. These exceptions are tested below. */
   for (const Unit::Dimension * dim = Unit::DimensionTable; dim < Unit::DimensionTableUpperBound; dim++) {
     for (const Unit::Representative * rep = dim->stdRepresentative(); rep < dim->representativesUpperBound(); rep++) {
-      if (strcmp(rep->rootSymbol(), "Hz") == 0 || strcmp(rep->rootSymbol(), "S") == 0 || strcmp(rep->rootSymbol(), "ha") == 0 || strcmp(rep->rootSymbol(), "L") == 0) {
+      if (strcmp(rep->rootSymbol(), "Hz") == 0 || strcmp(rep->rootSymbol(), "S") == 0 || strcmp(rep->rootSymbol(), "ha") == 0 || strcmp(rep->rootSymbol(), "L") == 0 || strcmp(rep->rootSymbol(), "yd") || strcmp(rep->rootSymbol(), "tsp") || strcmp(rep->rootSymbol(), "Tbsp") || strcmp(rep->rootSymbol(), "pt") || strcmp(rep->rootSymbol(), "qt") || strcmp(rep->rootSymbol(), "lgtn")) {
         continue;
       }
       static constexpr size_t bufferSize = 12;
       char buffer[bufferSize] = "1×";
       Unit::Builder(dim, rep, &Unit::EmptyPrefix).serialize(buffer+strlen("1×"), bufferSize-strlen("1×"), Preferences::PrintFloatMode::Decimal, Preferences::VeryShortNumberOfSignificantDigits);
-      assert_parsed_expression_simplify_to(buffer, buffer);
+      assert_parsed_expression_simplify_to(buffer, buffer, User, Radian, (rep->canOutputInSystem(Metric) ? Metric : Imperial));
       if (rep->isPrefixable()) {
         for (size_t i = 0; i < rep->outputPrefixesLength(); i++) {
           const Unit::Prefix * pre = rep->outputPrefixes()[i];