diff --git a/app/lib/zap/controller.js b/app/lib/zap/controller.js
index 794f867a..2387f280 100644
--- a/app/lib/zap/controller.js
+++ b/app/lib/zap/controller.js
@@ -284,6 +284,7 @@ class ZapController {
       this.sendMessage('lightningGrpcActive')
     } catch (err) {
       mainLog.warn('Unable to connect to Lighitnng gRPC interface: %o', err)
+      throw err
     }
   }
 
diff --git a/test/unit/__mocks__/electron.js b/test/unit/__mocks__/electron.js
index e4cb4e68..1840a834 100644
--- a/test/unit/__mocks__/electron.js
+++ b/test/unit/__mocks__/electron.js
@@ -9,5 +9,8 @@ module.exports = {
   },
   remote: jest.fn(),
   dialog: jest.fn(),
-  BrowserWindow: jest.fn()
+  BrowserWindow: jest.fn(),
+  ipcMain: {
+    on: jest.fn()
+  }
 }
diff --git a/test/unit/zap/controller.spec.js b/test/unit/zap/controller.spec.js
new file mode 100644
index 00000000..c9a6e18a
--- /dev/null
+++ b/test/unit/zap/controller.spec.js
@@ -0,0 +1,54 @@
+import ZapController from 'lib/zap/controller'
+import LndConfig from 'lib/lnd/config'
+
+jest.mock('lib/lnd/lightning')
+const Lightning = require('lib/lnd/lightning')
+
+describe('ZapController', function() {
+  describe('Constructor', () => {
+    beforeAll(() => {
+      this.controller = new ZapController()
+    })
+
+    describe('initial values', () => {
+      it('should set the "lndConfig" property to a new LndConfig instance', () => {
+        expect(this.controller.lndConfig).toBeInstanceOf(LndConfig)
+      })
+      it('should set the "splashScreenTime" property to 500', () => {
+        expect(this.controller.splashScreenTime).toEqual(500)
+      })
+      it('should set the "mainWindow" property to undefined', () => {
+        expect(this.controller.mainWindow).toBeUndefined()
+      })
+    })
+  })
+
+  describe('.startLightningWallet', () => {
+    describe('successful connection', () => {
+      beforeEach(() => {
+        Lightning.mockImplementation(() => ({
+          subscribe: jest.fn(),
+          connect: jest.fn().mockResolvedValue()
+        }))
+        this.controller = new ZapController()
+      })
+      it('should resolve with undefined', async () => {
+        await expect(this.controller.startLightningWallet()).resolves.toBeUndefined()
+        expect(this.controller.lightning.subscribe).toHaveBeenCalled()
+      })
+    })
+    describe('unsuccessful connection', () => {
+      beforeEach(() => {
+        Lightning.mockImplementation(() => ({
+          subscribe: jest.fn(),
+          connect: jest.fn().mockRejectedValue(new Error('Async error'))
+        }))
+        this.controller = new ZapController()
+      })
+      it('should reject an error', async () => {
+        await expect(this.controller.startLightningWallet()).rejects.toThrow('Async error')
+        expect(this.controller.lightning.subscribe).not.toHaveBeenCalled()
+      })
+    })
+  })
+})