How to check the front air bag sensors

[Vangelis Kokkevis <vangelisk@domain.elided>]

Hi all,
  I am posting this question for a net impaired friend.  He would like
to find out how to check the forward airbag sensors on a 91 spider.  The
airbag warning light is on and the codes he is getting are:

16      Failure to forward LH sensor
26      Failure to forward RH sensor

Any ideas how to troubleshoot these?

Thanks a lot,
Vangelis

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