A batch of late Zafiras built in October 2019 can have problems with water getting in to the passenger compartment via a poorly sealed wheel arch. This can lead to electrical problems including airbag malfunction.
Vauxhall issued a recall for this whereby they sealed the affected wheel arches and replaced any damaged components.
A problem on some Zafiras built in April 2016 is that a component of the steering / suspension system wasn't up to specification and so can allow the system to be damaged over time. When the car gets to higher mileage the part can fail entirely resulting in steering loss.
Vauxhall issued a recall for this in July 2016 and replaced the affected part (track rod end) on cars where it wasn't up to spec. This shouldn't be an issue now but worth checking that any car built in this month has been checked if you're buying.
A common problem on the Zafira is a failed boot locking switch located on the driver's side door, it stops opening and closing the boot the lock.
You'll need to have a replacement boot locking switch fitted to resolve the problem.
A known problem on Zafiras is the electrical wiring in the rear doors, sometimes it can fail and lead to problems unlocking the rear doors via the key fob.
Generally the solution to this is to replace the affected wiring, you'll need an auto electrician to look at this.
A common issue with Zafiras is faulty / damaged drop links. These are part of the suspension system and join other parts together for strength and stability. The go through a lot of stresses and can wear out, they have rubber bushes to absorb forces and reduce noise. When these fail in some way you'll hear the familiar knocking sound.
To resolve this you can try replacing the bushes, or just go for new drop links entirely which is probably a better idea if you've already taken everything apart.
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