User´s Manual - I+ME ACTIA GmbH
User´s Manual - I+ME ACTIA GmbH
User´s Manual - I+ME ACTIA GmbH
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Security access - send key<br />
The purpose of the service ($27) Security Access is to provide a way to access data and/or diagnostic<br />
services, which have restricted access for security, emissions, or safety reasons.<br />
The security concept uses a seed and key relationship. The seed and key are each 16-bit numbers (2<br />
byte). The key has to be sent to an ECU to enable ("unlock") Cat's access to specific services. The seed<br />
using an encryption algorithm can derive the key. Therefor an individual seed is stored on each ECU.<br />
CAT provides two already predefined setup levels of the Security Access service:<br />
- The Security Access – request seed (sub-function parameter = $01 or $03),<br />
- The Security Access – send key (sub-function parameter = $02 or $04).<br />
To setup the sub-function parameter to send key $02 or $04, the Setup button in the Main Diagnostic<br />
Setup window could activate the dialog box shown below.<br />
Sub-function parameter $02 is the send key level used for ECU programming via the SPS system.<br />
Sub-function parameter $04 is the send key level for enabling vehicle manufacturing specific device<br />
control restrictions (as opposed to having service device control restrictions enabled).<br />
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