diff --git a/src/math/p5.Vector.js b/src/math/p5.Vector.js
index f54667f6ee..9cbdecff94 100644
--- a/src/math/p5.Vector.js
+++ b/src/math/p5.Vector.js
@@ -2228,6 +2228,10 @@ p5.Vector = class {
  */
 
   setHeading(a) {
+    if (this.z !== undefined && this.z !== 0) {
+      throw new Error('setHeading() is only supported for 2D vectors.');
+    }
+
     if (this.isPInst) a = this._toRadians(a);
     let m = this.mag();
     this.x = m * Math.cos(a);
@@ -2235,6 +2239,8 @@ p5.Vector = class {
     return this;
   }
 
+
+
   /**
  * Rotates a 2D vector by an angle without changing its magnitude.
  *
diff --git a/test/unit/math/p5.Vector.js b/test/unit/math/p5.Vector.js
index ef3570ee0b..ab7a743c2d 100644
--- a/test/unit/math/p5.Vector.js
+++ b/test/unit/math/p5.Vector.js
@@ -1,3 +1,14 @@
+suite('p5.Vector.prototype.setHeading (invalid dimensions)', function () {
+  test('throws an error for vectors with non-zero z component', function () {
+    let v3 = new p5.Vector(1, 2, 3);
+
+    assert.throws(() => {
+      v3.setHeading(Math.PI / 2);
+    }, Error);
+  });
+});
+
+
 suite('p5.Vector', function() {
   var RADIANS = 'radians';
   var DEGREES = 'degrees';