UK Car Repair Questions? Ask a Mechanic for Answers ASAP
have you tested the battery to see if it is holding a charge? if the battery is holding a charge then the next step is to have the starter tested as it may have an excessive draw and if this is the case the starter would need replacement. most auto part stores will test the battery and the starter for free while its in the vehicle. i highly recommend this. its likely the starter even though it starts with a jump its likely drawing too much juice which is why it will crank with the extra power from the jumper cables
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