P0AA3

Hybrid/EV Battery Negative Contactor Circuit

Severity

🔴 High

Can you drive?

Do not drive — repair immediately

Approx. repair cost

$56–278 (est.)

Symptoms

The car goes into emergency mode
Reduced power or inability to start
Check Engine Light Is On
Hybrid system warning

Causes

Malfunction of the contactor itself
Open or short circuit in the circuit
Problems with the hybrid system control module
Corrosion of contacts or connectors
High voltage relay fault

How to Fix

Check the condition of the contactor and its circuit
Check connections and connectors for corrosion
Test contactor resistance
Check power and control signals
Replace faulty components

Related codes

P0AA1 P0AA2 P0AA4