diff --git a/apps/pwa/src/components/InstructionSheet.test.tsx b/apps/pwa/src/components/InstructionSheet.test.tsx
new file mode 100644
index 0000000..f0c1dbb
--- /dev/null
+++ b/apps/pwa/src/components/InstructionSheet.test.tsx
@@ -0,0 +1,90 @@
+/**
+ * InstructionSheet.test.tsx — wiring test for SettingsSheet "How to enable" fix (UAT-05-T4).
+ *
+ * Asserts:
+ *   - Clicking "How to enable" in SettingsSheet opens the InstructionSheet dialog
+ *   - The dialog has heading "How to enable notifications"
+ *   - onClose (the sheet-close prop) is NOT called when the dialog opens
+ */
+
+import React from 'react'
+import { describe, it, expect, vi, beforeEach } from 'vitest'
+import { render, screen, fireEvent } from '@testing-library/react'
+
+// ── Module mocks ──────────────────────────────────────────────────────────────
+
+vi.mock('../hooks/usePushSubscription.js', () => ({
+  usePushSubscription: vi.fn(() => ({
+    permission: 'denied' as NotificationPermission,
+    isSubscribed: false,
+    subscribe: vi.fn(),
+    setEnabled: vi.fn(),
+  })),
+  readNotificationsEnabled: vi.fn(() => false),
+}))
+
+// ── Minimal Notification stub (jsdom lacks it) ────────────────────────────────
+
+beforeEach(() => {
+  if (typeof globalThis.Notification === 'undefined') {
+    Object.defineProperty(globalThis, 'Notification', {
+      value: { permission: 'denied' },
+      writable: true,
+      configurable: true,
+    })
+  } else {
+    Object.defineProperty(globalThis.Notification, 'permission', {
+      value: 'denied',
+      writable: true,
+      configurable: true,
+    })
+  }
+})
+
+// ── Import component (after mocks) ────────────────────────────────────────────
+
+import { SettingsSheet } from './SettingsSheet.js'
+
+// ── Tests ─────────────────────────────────────────────────────────────────────
+
+describe('SettingsSheet — "How to enable" wiring (UAT-05-T4)', () => {
+  it('clicking "How to enable" opens the InstructionSheet dialog and does NOT call onClose', () => {
+    const onCloseSpy = vi.fn()
+    render(<SettingsSheet isOpen={true} onClose={onCloseSpy} />)
+
+    // No instruction dialog yet
+    expect(screen.queryByRole('dialog', { name: /re-enable notifications/i })).toBeNull()
+
+    // Click the "How to enable" button
+    const howToEnableBtn = screen.getByText('How to enable')
+    fireEvent.click(howToEnableBtn)
+
+    // The InstructionSheet dialog should now be visible
+    const instructionDialog = screen.getByRole('dialog', { name: /re-enable notifications/i })
+    expect(instructionDialog).toBeDefined()
+
+    // The heading inside the dialog
+    expect(screen.getByText('How to enable notifications')).toBeDefined()
+
+    // onClose (sheet close prop) must NOT have been called
+    expect(onCloseSpy).not.toHaveBeenCalled()
+  })
+
+  it('InstructionSheet "Done" button closes the instruction dialog without calling sheet onClose', () => {
+    const onCloseSpy = vi.fn()
+    render(<SettingsSheet isOpen={true} onClose={onCloseSpy} />)
+
+    // Open the instruction sheet
+    fireEvent.click(screen.getByText('How to enable'))
+    expect(screen.getByRole('dialog', { name: /re-enable notifications/i })).toBeDefined()
+
+    // Click Done — closes the instruction sheet
+    fireEvent.click(screen.getByText('Done'))
+
+    // Instruction dialog should be gone
+    expect(screen.queryByRole('dialog', { name: /re-enable notifications/i })).toBeNull()
+
+    // Sheet onClose must NOT have been called
+    expect(onCloseSpy).not.toHaveBeenCalled()
+  })
+})
diff --git a/apps/pwa/src/components/SettingsSheet.tsx b/apps/pwa/src/components/SettingsSheet.tsx
index 726a5e6..7419b87 100644
--- a/apps/pwa/src/components/SettingsSheet.tsx
+++ b/apps/pwa/src/components/SettingsSheet.tsx
@@ -24,6 +24,7 @@
 import { useEffect, useRef, useState } from 'react'
 import { X, Bell, AlertCircle, Loader2 } from 'lucide-react'
 import { usePushSubscription } from '../hooks/usePushSubscription.js'
+import { InstructionSheet } from './InstructionSheet.js'
 
 // CR-04: fetch VAPID key (from sessionStorage cache if available) for the
 // tap-gated subscribe() path.  Same logic as PushPermissionPrompt.
@@ -51,6 +52,7 @@ interface SettingsSheetProps {
 export function SettingsSheet({ isOpen, onClose }: SettingsSheetProps) {
   const { subscribe, permission, isSubscribed, setEnabled } = usePushSubscription()
   const [isTogglingOn, setIsTogglingOn] = useState(false)
+  const [instructionsOpen, setInstructionsOpen] = useState(false)
   // CR-04: pre-fetch the VAPID key into state so the toggle tap handler can call
   // subscribe(registration, vapidKey) without any network await before pushManager.subscribe().
   const [vapidKey, setVapidKey] = useState<string | null>(null)
@@ -370,7 +372,7 @@ export function SettingsSheet({ isOpen, onClose }: SettingsSheetProps) {
                 Notifications are blocked in your browser settings.{' '}
               </span>
               <button
-                onClick={onClose}
+                onClick={() => setInstructionsOpen(true)}
                 style={{
                   background: 'none',
                   border: 'none',
@@ -388,6 +390,10 @@ export function SettingsSheet({ isOpen, onClose }: SettingsSheetProps) {
           </div>
         )}
       </div>
+
+      {instructionsOpen && (
+        <InstructionSheet onClose={() => setInstructionsOpen(false)} />
+      )}
     </>
   )
 }