Car Electronics Installer how-to
How to Find a Parasitic Battery Drain
Drains kill batteries overnight.
Quick answer
Drains kill batteries overnight. In short: let; connect; measure, then complete the remaining steps below.
Step by step
Let the car sleep.
Connect an ammeter.
Measure the draw.
Pull fuses one by one.
Find the circuit.
Fix the cause.
Safety reminders for car electronics installers
- Disconnect batteries when needed
- Fuse all power wires
- Avoid airbag circuits
- Use eye protection
Key terms
Head unit · Amplifier · Subwoofer · Harness adapter · CAN bus · Remote starter: see the full car electronics installer glossary.