DSD Information System
Home >> Toyota >> 2021 >> Highlander LE, 4WD >> Repair and Diagnosis >> Engine Mechanical >> Starter >> Stop And Start System - Diagnostic Codes (2 Of 3) >> Stop And Start System >> DTC P323A-00: Backup Boost Converter "A"; DTC P323A-16: Backup Boost Converter "A" Circuit Voltage Below Threshold; DTC P323B-14: Backup Boost Converter "A" Control Circuit Circuit Short to Ground or Open; DTC P323B-29: Backup Boost Converter "A" Control Circuit Signal Invalid; DTC P323B-38: Backup Boost Converter "A" Control Circuit Signal Cycle Invalid [10/2022 - 11/2023] >> Typical Enabling Conditions

Typical Enabling Conditions

P323A, P323C (CASE1), P323D

All of the following conditions are met -
Battery voltage 8 V or higher
Write Inhibit permit
Time after Write status forbiddance to permit 0.5 seconds or more
Ignition switch ON
Time after ignition switch is off to ON 0.5 seconds or more
Starter OFF
Time after starter on to off 0.5 seconds or more
Engine stop and start ECU internal back up boost converter fail (P323C) Not detected
P323C (CASE2)

Monitor runs whenever the following DTCs are not stored None
All of the following conditions are met -
Time after engine stop and start ECU power ON 0.1 seconds or more
Back up boost converter control IC status signal frequency Less than 50 Hz