diff --git a/core/src/components/modal/modal.tsx b/core/src/components/modal/modal.tsx
index 1bd3597efb..4e2f52838e 100644
--- a/core/src/components/modal/modal.tsx
+++ b/core/src/components/modal/modal.tsx
@@ -290,14 +290,14 @@ export class Modal implements ComponentInterface, OverlayInterface {
     const triggerEl = (trigger !== undefined) ? document.getElementById(trigger) : null;
     if (!triggerEl) { return; }
 
-    const configureTriggerInteraction = (triggerEl: HTMLElement, modalEl: HTMLIonModalElement) => {
+    const configureTriggerInteraction = (trigEl: HTMLElement, modalEl: HTMLIonModalElement) => {
       const openModal = () => {
         modalEl.present();
       }
-      triggerEl.addEventListener('click', openModal);
+      trigEl.addEventListener('click', openModal);
 
       return () => {
-        triggerEl.removeEventListener('click', openModal);
+        trigEl.removeEventListener('click', openModal);
       }
     }
 
diff --git a/core/src/components/picker-internal/picker-internal.tsx b/core/src/components/picker-internal/picker-internal.tsx
index b544ddd117..507e794d33 100644
--- a/core/src/components/picker-internal/picker-internal.tsx
+++ b/core/src/components/picker-internal/picker-internal.tsx
@@ -374,6 +374,7 @@ export class PickerInternal implements ComponentInterface {
     const lastColumn = numericPickers[1];
 
     let value = inputEl.value;
+    let minuteValue;
     switch (value.length) {
       case 1:
         this.searchColumn(firstColumn, value);
@@ -396,7 +397,7 @@ export class PickerInternal implements ComponentInterface {
          * for a match in the minutes column
          */
         if (value.length === 1) {
-          const minuteValue = inputEl.value.substring(inputEl.value.length - 1);
+          minuteValue = inputEl.value.substring(inputEl.value.length - 1);
           this.searchColumn(lastColumn, minuteValue, 'end');
         }
         break;
@@ -417,7 +418,7 @@ export class PickerInternal implements ComponentInterface {
          * we can check the second value
          * for a match in the minutes column
          */
-        const minuteValue = (value.length === 1) ? inputEl.value.substring(1) : inputEl.value.substring(2);
+        minuteValue = (value.length === 1) ? inputEl.value.substring(1) : inputEl.value.substring(2);
 
         this.searchColumn(lastColumn, minuteValue, 'end');
         break;
diff --git a/core/src/components/radio/radio.tsx b/core/src/components/radio/radio.tsx
index e2e1d74b9b..69b04313ce 100644
--- a/core/src/components/radio/radio.tsx
+++ b/core/src/components/radio/radio.tsx
@@ -177,7 +177,7 @@ export class Radio implements ComponentInterface {
           disabled={disabled}
           tabindex="-1"
           id={inputId}
-          ref={el => this.nativeInput = el as HTMLInputElement}
+          ref={nativeEl => this.nativeInput = nativeEl as HTMLInputElement}
         />
       </Host>
     );
diff --git a/core/src/components/range/range.tsx b/core/src/components/range/range.tsx
index 76ade963ab..760a06cb43 100644
--- a/core/src/components/range/range.tsx
+++ b/core/src/components/range/range.tsx
@@ -552,8 +552,8 @@ interface RangeKnob {
   handleKeyboard: (name: KnobName, isIncrease: boolean) => void;
 }
 
-const renderKnob = (isRTL: boolean, { knob, value, ratio, min, max, disabled, pressed, pin, handleKeyboard, labelText, pinFormatter }: RangeKnob) => {
-  const start = isRTL ? 'right' : 'left';
+const renderKnob = (rtl: boolean, { knob, value, ratio, min, max, disabled, pressed, pin, handleKeyboard, labelText, pinFormatter }: RangeKnob) => {
+  const start = rtl ? 'right' : 'left';
 
   const knobStyle = () => {
     const style: any = {};
diff --git a/core/src/components/toggle/toggle.tsx b/core/src/components/toggle/toggle.tsx
index 5e32f2d2b9..54f5a31c4b 100644
--- a/core/src/components/toggle/toggle.tsx
+++ b/core/src/components/toggle/toggle.tsx
@@ -225,13 +225,13 @@ export class Toggle implements ComponentInterface {
   }
 }
 
-const shouldToggle = (isRTL: boolean, checked: boolean, deltaX: number, margin: number): boolean => {
+const shouldToggle = (rtl: boolean, checked: boolean, deltaX: number, margin: number): boolean => {
   if (checked) {
-    return (!isRTL && (margin > deltaX)) ||
-      (isRTL && (- margin < deltaX));
+    return (!rtl && (margin > deltaX)) ||
+      (rtl && (- margin < deltaX));
   } else {
-    return (!isRTL && (- margin < deltaX)) ||
-      (isRTL && (margin > deltaX));
+    return (!rtl && (- margin < deltaX)) ||
+      (rtl && (margin > deltaX));
   }
 };