Can I reject a used car because of a faulty battery?

I bought a used car less than two weeks ago. It's a 2016 reg. The battery has failed three times since I bought it. The first time a friend jump started it for me, the second time a mechanic used a power bank and he told me that the battery health life was at 20% so I should consider replacing it soon.

I drove the car yesterday, parked overnight and now the battery is dead again. I don't understand what is causing it. The lights are definitely off. There is an issue with the radio which means I can't tell if it's on or off (I knew this fault existed when buying the car - the dealership will be fixing it) but I had the mechanic disconnect the fuse to make sure it is not draining power from the battery without me knowing.

What can I ask of the dealership? Should they replace the battery for me? Can I return the car for a refund? Can I figure out what is draining the battery and stop that from happening? Or is that the dealership's responsibility?

Asked on 20 June 2023 by Lucy Clark

Answered by David Ross
Given how recently you purchased the car it is not unreasonable to ask the dealer to replace the battery if this is required but also find the fault that is causing the battery to be drained. The fact that the mechanic said the battery health is 20% suggests that it needs replacement.

We would suggest giving the dealer another opportunity to rectify the fault before taking more extreme measures such as rejecting the vehicle, assuming the problem is not serious. You are still well within the 28 day period since purchase so your consumer rights are as strong as they can be. If the dealer cannot fix the fault you do have the right to return the vehicle and ask for a refund or a replacement vehicle, you can read more about how to do this in our guide here:
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