P1600moderate severityPowertrain
ECM Battery Backup Circuit
on 2009 Toyota Matrix 2.4L I4 · FWD
What this code means
The ECM detected a loss of battery voltage at the BATT terminal.
Symptoms
- CEL
- Lost fuel trim values
- Intermittent stalling
- Difficulty starting
Common causes
- Corroded battery terminals
- Damaged EFI fuse
- Open BATT wiring
- Weak battery
Diagnostic steps
- Check battery terminals
- Test EFI fuse
- Inspect BATT wiring
- Check battery voltage
Repair notes
Clean terminals or replace fuse.
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Other Powertrain codes on this vehicle
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P0002
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P0003
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P0004
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P0010
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P0011
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P0012
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P0013
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P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
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