General Motors and LG are working to fix the issues that led to a recall of the Chevy Bolt over fire concerns.

GM originally recalled some Bolts in late 2020 over reports they could catch on fire while charging. In July, reports surfaced that some vehicles had caught on fire despite being serviced in the recall, leading GM to expand the recall.

The issue appears to be the result of defective LG batteries, and both companies are pulling out the stops to address the issue.

“Experts from GM and LG continue to work around the clock on the issues,” GM spokesman Dan Flores said, according to Reuters. “We are determined to do the right thing for our customers and resolve the problem once and for all. Once we are confident LG can provide us with good battery modules, we will begin repairs as quickly as we can.”

The fix will vary, depending on the specific Bolt model, with older vehicles having the entire battery pack replaced. In contrast, newer vehicles will only have the defective modules replaced.