C1261 on Kia: How to Diagnose & Fix
Manufacturer-Specific Chassis Code (Steering Angle Calibration or ABS Inlet Valve Solenoid)
1 Kia model · 1 documented issue · 1 critical · $50-$900 repair
C1261 on Kia by model: symptoms, diagnosis and fix
On 1.6T turbocharged K5 variants, some owners and NHTSA complainants have reported a hissing sound from the brake booster area upon brake pedal application, accompanied by a noticeably harder brake pedal and reduced power assistance. The GDi turbocharged engine uses an electric vacuum pump to supplement braking assist; failures or leaks in the vacuum pump, vacuum check valve, or booster hose connection reduce available vacuum and compromise brake pedal feel and stopping distance. This has been flagged as a safety concern in NHTSA filings.
Common Symptoms
- Hissing sound when brake pedal is pressed
- Hard or stiff brake pedal requiring significantly more force to stop
- Longer stopping distances than normal
- Brake warning light or low vacuum warning illumination
- Brake pedal feel improving after engine warms up then worsening again
How to Fix
Inspection of the vacuum pump, vacuum reservoir, check valve, and all vacuum lines connecting to the brake booster is required. The electric vacuum pump (Kia/Mobis part number 59100-L2000 or per VIN) may require replacement if output is below specification. The vacuum check valve (a common failure point) is a lower-cost item at approximately $20–$50. Full vacuum pump replacement is $300–$700 parts and labor.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Genuine Kia 28810-2M810 mechanical brake-vacuum pumpOEMKia 28810-2M810, superseded by 28810-2M831
Replace the engine-driven pump after a vacuum-output test confirms pump failure Fitment/availability: 2021-2024 Kia K5 with 1.6L Gamma-II turbo; seller shows supersession to 28810-2M831. Confirm VIN and current EPC before ordering, and d…
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C1261 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does C1261 mean on a Kia?
C1261 stands for "Manufacturer-Specific Chassis Code (Steering Angle Calibration or ABS Inlet Valve Solenoid)." C1261 is a manufacturer-specific chassis code with meaning that varies by maker; reported definitions include a wheel/steering angle sensor not-calibrated condition (Kia) and a left front inlet valve solenoid malfunction in the ABS (Chevrolet/GM). In general it indicates that a chassis/ABS control module detected a calibration problem or an electrical fault in a circuit it monitors. Setting this code typically disables or limits ABS and traction/stability control and lights the related warnings. Confirm the exact definition for your specific make and model using a capable scan tool or factory service data before repair. On Kia it is documented across 1 model: K5.
What are the most common causes of C1261?
The most common causes of C1261 are: Steering/wheel angle sensor not calibrated, Faulty steering angle sensor, ABS inlet valve solenoid circuit fault (GM applications), Wiring or connector damage / corrosion, ABS/stability control module (HCU) fault, Open or short circuit in the affected circuit. The specific cause varies by vehicle.
How much does it cost to fix C1261 on a Kia?
Published repair estimates on Kia range from $50 to $900 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
Looking for C1261 on a different make?
View C1261 across all makes →Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.