Rear belt pretensioner - connectors
 

My 2008 V70 2.4 SE Lux keeps bringing up the SRS fault due to the middle belt pretensioner. I have had the pretensioner replaced in 2022 which cured the fault for nearly two years, but it's returned. The code can be cleared, but then returns anywhere between immediately to a few weeks. I can't believe the new pretensioner is duff already, I suspect a high resistance joint somewhere as the car is a family car with muddy boots, dogs etc in regular transit.

Can anybody provide pointers for how I locate all the various connectors this circuit may contain, and any other tips for diagnosing this? I don't have VIDA but I do have an iCarSoft reader. Looking at previous posts there is a resistance check you can do, but I don't know what the resistance should be.

Many thanks

David