Hyundai EV Diagnostics & Fault Manuals

Hyundai E-GMP 800V electric vehicle architecture, Integrated Charging Control Unit (ICCU), and battery management.

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Equipment Models

Hardware families produced by Hyundai EV

1 Series

Ioniq 5 & Ioniq 6

1 guides

Class: E-GMP 800V High-Speed Architecture

Browse Fault Codes

Indexed Error Codes for Hyundai EV

Machine-verified error code diagnostic walkthroughs

1 Manuals

CODE DTC P1A90 Ioniq 5 & Ioniq 6 Critical

ICCU Integrated Charging Control Unit Failure Fix

Hyundai Ioniq 5 and Ioniq 6 trigger DTC P1A90 accompanied by audible 'pop' from beneath the rear seats, dashboard warning 'Check Electric Vehicle System', and loss of 12V auxiliary power. Caused by internal MOSFET overcurrent thermal fatigue in the Integrated Charging Control Unit (ICCU) LDC circuit.

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