diff --git a/src/api/viya/spec/uploadTables.spec.ts b/src/api/viya/spec/uploadTables.spec.ts
new file mode 100644
index 0000000..529c6e2
--- /dev/null
+++ b/src/api/viya/spec/uploadTables.spec.ts
@@ -0,0 +1,67 @@
+import { RequestClient } from '../../../request/RequestClient'
+import * as convertToCsvModule from '../../../utils/convertToCsv'
+import { uploadTables } from '../uploadTables'
+
+const requestClient = new (<jest.Mock<RequestClient>>RequestClient)()
+
+describe('uploadTables', () => {
+  beforeEach(() => {
+    setupMocks()
+  })
+
+  it('should return a list of uploaded files', async () => {
+    const data = { foo: 'bar' }
+
+    const files = await uploadTables(requestClient, data, 't0k3n')
+
+    expect(files).toEqual([{ tableName: 'foo', file: 'test-file' }])
+    expect(requestClient.uploadFile).toHaveBeenCalledTimes(1)
+    expect(requestClient.uploadFile).toHaveBeenCalledWith(
+      '/files/files#rawUpload',
+      'Test CSV',
+      't0k3n'
+    )
+  })
+
+  it('should throw an error when the CSV exceeds the maximum length', async () => {
+    const data = { foo: 'bar' }
+    jest
+      .spyOn(convertToCsvModule, 'convertToCSV')
+      .mockImplementation(() => 'ERROR: LARGE STRING LENGTH')
+
+    const error = await uploadTables(requestClient, data, 't0k3n').catch(
+      (e) => e
+    )
+
+    expect(requestClient.uploadFile).not.toHaveBeenCalled()
+    expect(error.message).toEqual(
+      'The max length of a string value in SASjs is 32765 characters.'
+    )
+  })
+
+  it('should throw an error when the file upload fails', async () => {
+    const data = { foo: 'bar' }
+    jest
+      .spyOn(requestClient, 'uploadFile')
+      .mockImplementation(() => Promise.reject('Upload Error'))
+
+    const error = await uploadTables(requestClient, data, 't0k3n').catch(
+      (e) => e
+    )
+
+    expect(error).toContain('Error while uploading file.')
+  })
+})
+
+const setupMocks = () => {
+  jest.restoreAllMocks()
+  jest.mock('../../../utils/convertToCsv')
+  jest
+    .spyOn(convertToCsvModule, 'convertToCSV')
+    .mockImplementation(() => 'Test CSV')
+  jest
+    .spyOn(requestClient, 'uploadFile')
+    .mockImplementation(() =>
+      Promise.resolve({ result: 'test-file', etag: '' })
+    )
+}
diff --git a/src/api/viya/uploadTables.ts b/src/api/viya/uploadTables.ts
index 13bf7b8..e7f5b66 100644
--- a/src/api/viya/uploadTables.ts
+++ b/src/api/viya/uploadTables.ts
@@ -8,12 +8,6 @@ export async function uploadTables(
   accessToken?: string
 ) {
   const uploadedFiles = []
-  const headers: any = {
-    'Content-Type': 'application/json'
-  }
-  if (accessToken) {
-    headers.Authorization = `Bearer ${accessToken}`
-  }
 
   for (const tableName in data) {
     const csv = convertToCSV(data[tableName])
diff --git a/src/auth/getAccessToken.ts b/src/auth/getAccessToken.ts
index 0b11340..d51833e 100644
--- a/src/auth/getAccessToken.ts
+++ b/src/auth/getAccessToken.ts
@@ -1,4 +1,5 @@
-import { SasAuthResponse } from '@sasjs/utils'
+import { SasAuthResponse } from '@sasjs/utils/types'
+import { prefixMessage } from '@sasjs/utils/error'
 import * as NodeFormData from 'form-data'
 import { RequestClient } from '../request/RequestClient'
 
@@ -44,6 +45,9 @@ export async function getAccessToken(
       headers
     )
     .then((res) => res.result as SasAuthResponse)
+    .catch((err) => {
+      throw prefixMessage(err, 'Error while getting access token')
+    })
 
   return authResponse
 }
diff --git a/src/auth/spec/getAccessToken.spec.ts b/src/auth/spec/getAccessToken.spec.ts
new file mode 100644
index 0000000..e4fa00f
--- /dev/null
+++ b/src/auth/spec/getAccessToken.spec.ts
@@ -0,0 +1,75 @@
+import { AuthConfig } from '@sasjs/utils'
+import * as NodeFormData from 'form-data'
+import { generateToken, mockAuthResponse } from './mockResponses'
+import { RequestClient } from '../../request/RequestClient'
+import { getAccessToken } from '../getAccessToken'
+
+const requestClient = new (<jest.Mock<RequestClient>>RequestClient)()
+
+describe('getAccessToken', () => {
+  it('should attempt to refresh tokens', async () => {
+    setupMocks()
+    const access_token = generateToken(30)
+    const refresh_token = generateToken(30)
+    const authConfig: AuthConfig = {
+      access_token,
+      refresh_token,
+      client: 'cl13nt',
+      secret: 's3cr3t'
+    }
+    jest
+      .spyOn(requestClient, 'post')
+      .mockImplementation(() =>
+        Promise.resolve({ result: mockAuthResponse, etag: '' })
+      )
+    const token = Buffer.from(
+      authConfig.client + ':' + authConfig.secret
+    ).toString('base64')
+
+    await getAccessToken(
+      requestClient,
+      authConfig.client,
+      authConfig.secret,
+      authConfig.refresh_token
+    )
+
+    expect(requestClient.post).toHaveBeenCalledWith(
+      '/SASLogon/oauth/token',
+      expect.any(NodeFormData),
+      undefined,
+      expect.stringContaining('multipart/form-data; boundary='),
+      {
+        Authorization: 'Basic ' + token
+      }
+    )
+  })
+
+  it('should handle errors while refreshing tokens', async () => {
+    setupMocks()
+    const access_token = generateToken(30)
+    const refresh_token = generateToken(30)
+    const authConfig: AuthConfig = {
+      access_token,
+      refresh_token,
+      client: 'cl13nt',
+      secret: 's3cr3t'
+    }
+    jest
+      .spyOn(requestClient, 'post')
+      .mockImplementation(() => Promise.reject('Token Error'))
+
+    const error = await getAccessToken(
+      requestClient,
+      authConfig.client,
+      authConfig.secret,
+      authConfig.refresh_token
+    ).catch((e) => e)
+
+    expect(error).toContain('Error while getting access token')
+  })
+})
+
+const setupMocks = () => {
+  jest.restoreAllMocks()
+  jest.mock('../../request/RequestClient')
+}