Thank you for your question and let me apologise for the delay in your answer. My name is Steve and I am a fully qualified vehicle technician with over thirty years in the trade. Hopefully I can help.
The PATS module on your Mondeo should be up under the instrument panel lower trim:
The Manual states:
Disconnect battery, for right hand drive vehicles remove the instrument panel righthand side lower trim panel.
Detach the Passive anti-theft system (PATS) module from the retaining bracket.
I have attached a screenshot of the position.
The manual also advises that:
When installing a new immobiliser (PATS) module the red master key must be the first key used to start.
I would also add that the system changed in 1998 and after that point the PATS was incorporated into the powertrain control module.
I hope this answers your question but do feel free to ask for any further information using this thread, and I again I apologise that it took so long for you to get an answer.
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