Uploaded February 2026 | Updated September 2026, 3 weeks ago

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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.

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⚠️ 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