Magento 2.0.2 installed . FedEx credentials entered. Checkout hangs on entering pincode .

[Superiornova]

Unable to get FedEx rate on checkout. Error log displays soap error ...... Not a valid utf8 encoding. Cannot proceed to payment . 

[Superiornova]

[2016-02-01 04:33:01] main.DEBUG: array (
'request' =>
array (
'WebAuthenticationDetail' =>
array (
'UserCredential' =>
array (
'Key' => 'æjÉ1çÀ×Î_‰',
'Password' => 'ÁAþub›½>y¾+`kÆQªúâófû¼¸',
),
),
'ClientDetail' =>
array (
'AccountNumber' => '¶Ì]÷Ã3º',
'MeterNumber' => 'Ü”}ïw2Pí',
),
'Version' =>
array (
'ServiceId' => 'crs',
'Major' => '10',
'Intermediate' => '0',
'Minor' => '0',
),
'RequestedShipment' =>
array (
'DropoffType' => 'REGULAR_PICKUP',
'ShipTimestamp' => '2016-02-01T04:33:01+00:00',
'PackagingType' => 'YOUR_PACKAGING',
'TotalInsuredValue' =>
array (
'Amount' => 151.0,
'Currency' => 'INR',
),
'Shipper' =>
array (
'Address' =>
array (
'PostalCode' => '400072',
'CountryCode' => 'IN',
),
),
'Recipient' =>
array (
'Address' =>
array (
'PostalCode' => '10001',
'CountryCode' => 'US',
'Residential' => false,
),
),
'ShippingChargesPayment' =>
array (
'PaymentType' => 'SENDER',
'Payor' =>
array (
'AccountNumber' => '¶Ì]÷Ã3º',
'CountryCode' => 'IN',
),
),
'CustomsClearanceDetail' =>
array (
'CustomsValue' =>
array (
'Amount' => 151.0,
'Currency' => 'INR',
),
),
'RateRequestTypes' => 'LIST',
'PackageCount' => '1',
'PackageDetail' => 'INDIVIDUAL_PACKAGES',
'RequestedPackageLineItems' =>
array (
0 =>
array (
'Weight' =>
array (
'Value' => 2.0,
'Units' => 'KG',
),
'GroupPackageCount' => 1,
'InsuredValue' =>
array (
'Amount' => 151.0,
'Currency' => 'INR',
),
),
),
),
),
'result' =>
array (
'error' => 'SOAP-ERROR: Encoding: string \'\\xe6...\' is not a valid utf-8 string',
'code' => 0,
),
) {"is_exception":false} []

[Superiornova]

changed to php5.6 and it worked. seems to be an issue with php 7 compatibility with fedex module.  does anyone know a fix to make it work on php 7?