C1604
ABS / stability-control fault code, listed for 7 vehicle lines from Hyundai, Kia. What it means on each one, from published sources, and when the module is the cause.
What C1604 means
ECU hardware error: the HECU detects a fault in its own IC components (memory, register, A/D converter)
On: 2011-2015 Hyundai Elantra (MD sedan, JK coupe) · 2010-2015 Hyundai Tucson (LM / ix35)
ECU hardware error: internal memory or processor fault detected by the control unit
On: 2007-2012 Hyundai Santa Fe (CM)
HECU hardware error: EEPROM data mismatch or abnormal RAM, register, interrupt, timer or A/D operation detected by the HECU processors; cause: faulty HECU
On: 2011-2015 Kia Optima (TF, gasoline) · 2011-2015 Kia Sorento (XM) · 2010-2013 Kia Soul (AM) · 2016-2021 Kia Sportage (QL)
Is it the ABS module?
Check the cheap things first: battery voltage and the main fuses for the ABS pump and module, the ground straps, the module connector (corrosion, a pushed-back pin) and, for wheel-speed codes, the sensor and its wiring at each wheel. If those are good and the code returns as soon as it is cleared — or the scan tool cannot talk to the ABS module at all — the module itself is the likely cause, and that is what we repair.
Vehicles that set C1604
- 2011-2015 Hyundai Elantra (MD sedan, JK coupe)Mando ABS / ESC · 3 part numbers · recall listed
- 2007-2012 Hyundai Santa Fe (CM)Bosch ABS / ESP 8 · 7 part numbers
- 2010-2015 Hyundai Tucson (LM / ix35)Mando ABS / ESC · 2 part numbers · recall listed
- 2011-2015 Kia Optima (TF, gasoline)Mando ABS / ESC · 2 part numbers · recall listed
- 2011-2015 Kia Sorento (XM)Mando ABS / ESC · 3 part numbers · recall listed
- 2010-2013 Kia Soul (AM)Mando ABS / ESC · 7 part numbers · recall listed
- 2016-2021 Kia Sportage (QL)Mando ABS / ESC · 2 part numbers · recall listed
C1604 by vehicle
What does C1604 mean on a Hyundai Elantra (MD sedan, JK coupe)?
On the 2011-2015 Hyundai Elantra (MD sedan, JK coupe) it means: ECU hardware error: the HECU detects a fault in its own IC components (memory, register, A/D converter). That vehicle uses Mando brake hydraulic unit assembly (ABS module with integrated controller PCB). We repair it as part of the Mando ABS / ESC family, from $499.
What does C1604 mean on a Hyundai Santa Fe (CM)?
On the 2007-2012 Hyundai Santa Fe (CM) it means: ECU hardware error: internal memory or processor fault detected by the control unit. That vehicle uses Bosch 8.0. We repair it as part of the Bosch ABS / ESP 8 family, from $499.
What does C1604 mean on a Hyundai Tucson (LM / ix35)?
On the 2010-2015 Hyundai Tucson (LM / ix35) it means: ECU hardware error: the HECU detects a fault in its own IC components (memory, register, A/D converter). That vehicle uses Mando brake hydraulic unit assembly. We repair it as part of the Mando ABS / ESC family, from $499.
What does C1604 mean on a Kia Optima (TF, gasoline)?
On the 2011-2015 Kia Optima (TF, gasoline) it means: HECU hardware error: EEPROM data mismatch or abnormal RAM, register, interrupt, timer or A/D operation detected by the HECU processors; cause: faulty HECU. That vehicle uses Mando hydraulic unit assembly / ABS pump control module (HECU). We repair it as part of the Mando ABS / ESC family, from $499.
What does C1604 mean on a Kia Sorento (XM)?
On the 2011-2015 Kia Sorento (XM) it means: HECU hardware error: EEPROM data mismatch or abnormal RAM, register, interrupt, timer or A/D operation detected by the HECU processors; cause: faulty HECU. That vehicle uses Mando ABS hydraulic module. We repair it as part of the Mando ABS / ESC family, from $499.
What does C1604 mean on a Kia Soul (AM)?
On the 2010-2013 Kia Soul (AM) it means: HECU hardware error: EEPROM data mismatch or abnormal RAM, register, interrupt, timer or A/D operation detected by the HECU processors; cause: faulty HECU. That vehicle uses Mando ABS pump control module. We repair it as part of the Mando ABS / ESC family, from $499.
Still not sure?
Send us C1604, a photo of the module label and your VIN — we tell you whether the module is the likely cause and what it costs, before you pull anything. Asking costs nothing.
C1604 keeps coming back after the checks? Fix the module — from $499.
Look up your part number and order online — we email you a prepaid label to our lab. Or send us a photo of the label and your VIN first, and we'll tell you what you have and what it costs.
Back with your VIN and coding · can’t be repaired? repair price back, minus shipping · 1-year warranty · rush 2–3 days +$100
Call (817) 505-4201 · 📱 Text us a photo of the module label · Confirm my module first — free · Email repairs@absmodulelab.com