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![JohnMcTavish48](themes/aaAle/images/interface/profile-pic-placeholder.47cf740a.png)
Does leaving the old but still in good condition and fully charged battery in the vehicle when fitting a new alternator void the alternator warranty? Do you have to have a new battery to keep the alternator warranty?
2009 jeep Cherokee KK 3.7V6 petrol
![Anon](/assets/aa/aa-avatar.png?m=1466990309)
Hi there,
The supplier of the alternator should be able to advise on the warranty conditions, but I have never heard of (and would think it very unusual) the requirement to have a new battery fitted if an alternator is replaced.
![Anon](/assets/aa/aa-avatar.png?m=1466990309)
Certainly the battery state of health should be checked and the battery replaced if required in order for the alternator to do its job effectively.