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“Battery Keeps Dying” — Parasitic Drain Test That Wasn’t

Customer complaint: battery keeps going dead — even after a new battery and alternator. In this diagnostic walk-through, we verify charging system operation, measure key-off current with an inductive low-amp clamp, isolate a suspected parasitic drain through fuse testing, and trace the circuit to the BCM-controlled inadvertent power relay. The twist: the “draw” was actually a normal 20-minute module timer — not a fault. This case is a great lesson in parasitic drain testing procedure, module timeouts, and why you must let systems go to sleep before chasing current draw. 🔧 Looking for Deeper Training? Join ScannerDanner Premium for next-level diagnostics training: 👉 Join Here – 14 Days for $1 https://www.scannerdanner.com/join-scannerdanner-premium.html On ScannerDanner Premium, you’ll get: • In-depth classroom lectures straight from my book • Exclusive case studies with live vehicles pulled into class • Real-time troubleshooting using proven methods • Ability to post help requests on our forum • Fundamental training on automotive electrical & electronics diagnostics 📘 Want to Learn More About Diagnostics? Check out my field manual Engine Performance Diagnostics, available as both an eBook and paperback: 👉 https://linktr.ee/scannerdanner ScannerDanner Tools: https://linktr.ee/scannerdanner ⚠️ Disclaimer: ScannerDanner LLC is not responsible for misuse, unauthorized changes, or incorrect application of any information provided. Always follow proper safety protocols when using tools, equipment, or procedures discussed in this video. Use this content at your own risk. 00:00 — Customer Complaint 01:32 — Charging System Verification 05:20 — Current Draw Measurement 08:25 — Aftermarket Remote Starter Check 12:00 — Pulling Fuses 16:04 — Fuse Voltage Drop Testing 23:00 — Service Information Review 27:32 — Relay Circuit Analysis 35:39 — BCM Data & Timer Identification 39:36 — Key-Off Timeout Test 45:02 — Relay Timeout Confirmed 47:28 — Final Review