diff --git a/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/jest.config.js b/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/jest.config.js
index 07ccfd28a8..9a46cb29ff 100644
--- a/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/jest.config.js
+++ b/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/jest.config.js
@@ -6,7 +6,7 @@ module.exports = {
   coverageThreshold: {
     global: {
       branches: 80,
-      functions: 60,
+      functions: 80,
       lines: 80,
       statements: 80
     }
diff --git a/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/lambda.test.ts b/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/lambda.test.ts
index 09086385d8..ccc3277f2d 100644
--- a/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/lambda.test.ts
+++ b/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/lambda.test.ts
@@ -4,8 +4,8 @@ import { mocked } from 'ts-jest/utils';
 
 jest.mock('./syncer/syncer');
 
-describe('Test scale up lambda wrapper.', () => {
-  it('Scale without error should resolve.', async () => {
+describe('Test download sync wrapper.', () => {
+  it('Test successful download.', async () => {
     const mock = mocked(sync);
     mock.mockImplementation(() => {
       return new Promise((resolve) => {
@@ -15,7 +15,7 @@ describe('Test scale up lambda wrapper.', () => {
     await expect(handler({}, {})).resolves;
   });
 
-  it('Scale without error should resolve2 . ', async () => {
+  it('Test wrapper with returning an error. ', async () => {
     const mock = mocked(sync);
     mock.mockRejectedValue(new Error(''));
 
diff --git a/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/lambda.ts b/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/lambda.ts
index 4f38cdfa72..12d53f26e5 100644
--- a/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/lambda.ts
+++ b/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/lambda.ts
@@ -2,16 +2,13 @@ import { sync } from './syncer/syncer';
 import { logger } from './syncer/logger';
 
 // eslint-disable-next-line
-export const handler = async (event: any, context: any): Promise<void> => {
+export async function handler(event: any, context: any): Promise<void> {
   logger.setSettings({ requestId: context.awsRequestId });
   logger.debug(JSON.stringify(event));
 
-  return new Promise((resolve) => {
-    sync()
-      .then(() => resolve())
-      .catch((e: Error) => {
-        logger.warn('Ignoring error:', e);
-        resolve();
-      });
-  });
-};
+  try {
+    await sync();
+  } catch (e) {
+    logger.warn('Ignoring error:', e);
+  }
+}
diff --git a/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/syncer/syncer.test.ts b/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/syncer/syncer.test.ts
index 33851f5123..fc17f1fef5 100644
--- a/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/syncer/syncer.test.ts
+++ b/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/syncer/syncer.test.ts
@@ -3,6 +3,10 @@ import listReleases from '../../test/resources/github-list-releases.json';
 import listReleasesEmpty from '../../test/resources/github-list-releases-empty-assets.json';
 import listReleasesNoLinux from '../../test/resources/github-list-releases-no-linux.json';
 import listReleasesNoArm64 from '../../test/resources/github-list-releases-no-arm64.json';
+import { S3 } from 'aws-sdk';
+import axios from 'axios';
+import { request } from 'http';
+import { EventEmitter, PassThrough, Readable } from 'stream';
 
 const mockOctokit = {
   repos: {
@@ -13,9 +17,23 @@ jest.mock('@octokit/rest', () => ({
   Octokit: jest.fn().mockImplementation(() => mockOctokit),
 }));
 
+// mock stream for Axios
+const mockResponse = `{"data": 123}`;
+const mockStream = new PassThrough();
+mockStream.push(mockResponse);
+mockStream.end();
+
+jest.mock('axios');
+const mockedAxios = axios as jest.Mocked<typeof axios>;
+mockedAxios.request.mockResolvedValue({
+  data: mockStream,
+});
+
 const mockS3 = {
   getObjectTagging: jest.fn(),
-  upload: jest.fn(),
+  upload: jest.fn().mockImplementation(() => {
+    return { promise: jest.fn(() => Promise.resolve()) };
+  }),
 };
 jest.mock('aws-sdk', () => ({
   S3: jest.fn().mockImplementation(() => mockS3),
@@ -27,6 +45,8 @@ beforeEach(() => {
   jest.clearAllMocks();
 });
 
+jest.setTimeout(60 * 1000);
+
 describe('Synchronize action distribution.', () => {
   beforeEach(() => {
     process.env.S3_BUCKET_NAME = bucketName;
diff --git a/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/syncer/syncer.ts b/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/syncer/syncer.ts
index d7478cf5d9..4787bf7602 100644
--- a/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/syncer/syncer.ts
+++ b/modules/runner-binaries-syncer/lambdas/runner-binaries-syncer/src/syncer/syncer.ts
@@ -125,7 +125,7 @@ export async function sync(): Promise<void> {
   const currentVersion = await getCachedVersion(s3, cacheObject);
   logger.debug('latest: ' + currentVersion);
   if (currentVersion === undefined || currentVersion != actionRunnerReleaseAsset.name) {
-    uploadToS3(s3, cacheObject, actionRunnerReleaseAsset);
+    await uploadToS3(s3, cacheObject, actionRunnerReleaseAsset);
   } else {
     logger.debug('Distribution is up-to-date, no action.');
   }