Subaru did not say whether it was aware of any accidents or injuries as a result of the defect, which affects certain 2006 to 2012 Legacy, Outback, Tribeca and Forester vehicles equipped with an optional accessory light.
"A short circuit can develop when either the puddle light or connector are exposed to an electrolytic moisture source (i.e. salt water) and it penetrates the circuit board of the puddle light or the pins of the puddle light connector," the company wrote in a notice to federal safety regulators.
"This may generate heat which may melt the plastic resulting in smoke or fire."
Subaru said the first complaint of "smoke and/or fire" was in 2007, adding that the company had made several changes to try to fix it.
After determining in a review begun in 2011 that the defect related to safety, the company ordered the recall.
Affected vehicles will be equipped with an additional fused-harness, free of charge.