P1602 Battery Voltage Monitor Malfunction

Category: Powertrain - Computer and Auxiliary Controls
Severity: Check Engine Light
Applies to: Camry, Corolla, RAV4, Tacoma

What does P1602 mean on a Toyota?

P1602 — Battery Voltage Monitor Malfunction. This Toyota-enhanced code applies to Camry, Corolla, RAV4, Tacoma.

Common causes of P1602

Failing battery voltage monitor circuit
Corroded battery terminals skewing readings
Weak battery
Open monitor wire
ECM input fault

How to fix P1602

Load-test the battery
Clean terminals and grounds
Compare monitor readings to a meter
Check monitor wiring
Repair wiring or service the battery