FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Enhanced Testing



C1604 - ECU Hardware Error






General Description
The HECU is composed of a ECU (Electronic Control Unit) and a HCU (Hydraulic Control Unit) , so the HECU hardware includes all solenoid valves inside the unit as well as the ECU.

DTC Description
The HECU monitors the operation of the IC components such as memory, register, A/D converter and so on. The HECU sets this code when the EEPROM data read by the master processor is different than prior data writed, or when the master/slave processor detects abnormal operation in RAM, Status Register, Interrupt, Timer, A/D converter or cycle time.

Detecting Condition