2018 Cadillac CTS-V — battery dies after the car sits for a weekend — second opinion before I spend money

Intermittent stuff lies if you only catch it once. Get a real battery/charging test on the 2018 Cadillac CTS-V, not just resting voltage, before blaming a module. You'll know quickly if you're on the wrong tree. On “v — battery dies after the car,” that was the fork that mattered for me. This is from a 2018 Cadillac CTS-V in New Jersey with 72,500 miles. Not gospel, but it saved me a headache. I'll poke at it this weekend.

I'd want a measurement, not a hunch. Get a real battery/charging test on the 2018 Cadillac CTS-V, not just resting voltage, before blaming a module. You'll know quickly if you're on the wrong tree. Stop there until you know. Video is ugly but it shows the hesitation.

This is usually cheaper to test than to guess. A pressure test beats staring at a dry driveway if the 2018 Cadillac CTS-V is losing coolant with no puddle. Don't erase codes until someone who can help has seen them. This is from a 2018 Cadillac CTS-V in New Jersey with 72,500 miles. Take it or leave it — that's what I'd do. I refuse to clear codes until someone else sees them.