(Bloomberg) — Volkswagen AG luxury brand Audi is recalling its first all-electric vehicle E-Tron due to the risk of a battery fire.

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The company issued a voluntary recall of approximately 540 E-Tron SUV models sold in the U.S. because of a risk that moisture can seep into the battery cell through a wiring harness glitch, spokesman Mark Dahncke said. The company isn’t aware of any fires or injuries because of the flaw, which affects a total of 1,644 models, he said.

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The E-Tron, which went on sale in the U.S. in April, is Audi’s first fully-electric car and one in a wave of contenders from traditional automakers looking to challenge Tesla Inc.’s dominance of the segment. While electric vehicles are no more prone to accidents or fires than gasoline-powered cars — and might be less so, according the National Highway Traffic Safety Administration — the lithium-ion battery technology that powers them is still evolving, and there is no consensus on safe system design.

Audi said there have been five instances globally where a battery fault light turned on because of the moisture issue. It began contacting E-Tron owners in the U.S. last week, prior to a warning from federal safety regulators, and should have a repair available by August.

“We are applying an abundance of caution as no such incidents have been reported globally,” the company said in a statement.

Audi said it’s offering E-Tron owners loaner vehicles and an $800 cash card to cover gas or incidentals during the recall period, as well as free roadside assistance. There are still E-Trons unaffected by the recall available for sale, it said.