DTC C1604 Ecu Hardware Error: DTC Detecting Condition

WARNING: This page is about a different car, the 2007 Kia Optima, 2007 Kia Magentis, 2006 Kia Optima, and 2006 Kia Magentis. However, it is still accessible from the selected car via links, so may be relevant.

DTC DETECTING CONDITION CHART

Item	Detecting Condition	Possible cause
DTC Strategy	Internal monitoring	Faulty HECU
Detect Mode	Initial Check Outside the ABS control cycle Inside the ABS control cycle Diagnosis mode Failure mode
Enable Conditions	When the MCU can't erase or write a data of the EEPROM. When the master/slave processor detects abnormal operation in RAM, ROM, INTERRUPT, TIMER, A/D CONVERTER, CYCLE TIME.
Fail Safe	System down. The ABS/EBD/TCS/ESC functions are inhibited. The valve relay and all solenoids are prevented from being switched on. The ABS/EBD/ESC warning lamps are activated.