C1A16: How to Diagnose & Fix — Manufacturer-Specific Chassis Code (Nissan/Infiniti: Radar/Distance Sensor Obstruction or Misalignment)
5 vehicles · 2 makes · $200-$1,800 repair
How to diagnose and fix C1A16: most-reported vehicles
Ranked by owner reports. Each card gives the symptoms, how to confirm the cause, the fix, parts and sources for that vehicle.
Nissan Rogue · 2021–2025
Multiple owners of the current-generation Rogue report the forward collision warning / automatic emergency braking system issuing sudden alerts, disabling itself, or in some cases braking unexpectedly with no obstacle present. Complaints commonly mention 'Front radar unavailable due to obstruction' or related warning messages in clear weather, sometimes recurring after restart. This is a safety-related issue because it can cause abrupt deceleration or loss of driver-assistance functions when expected.
Common Symptoms
- Automatic emergency braking activates with no vehicle ahead
- Forward collision warning chime or dash warning appears unexpectedly
- Front radar obstruction or unavailable message
- ProPILOT Assist disables itself
- Cruise control or driver-assist features become unavailable
How to Fix
Scan the ADAS modules for stored faults, inspect radar sensor mounting and alignment, and verify the front emblem/radar cover is clean and undamaged. Nissan service procedures typically involve radar aiming/calibration, checking harness/connectors, and replacing the radar sensor or related components if faults persist. If the vehicle has collision damage, bumper cover fitment and bracket alignment should be checked carefully because small misalignment can trigger repeated faults.
Owner tips & cautions
- TipClean the front emblem/radar area and inspect for bumper misalignment or prior minor impact before replacing parts; many owners report intermittent warnings caused by sensor aiming issues.
Infiniti QX60 · 2022–2025
Owners have reported unexpected forward collision warnings and abrupt braking events with no obvious obstacle ahead, especially in traffic, on curves, or near roadside objects. These complaints are tied to the QX60's ADAS sensor/camera interpretation rather than a conventional brake hardware fault. Sudden braking can create a rear-impact hazard and is one of the more serious owner-reported safety concerns on the current generation.
Common Symptoms
- Forward collision warning with no vehicle ahead
- Unexpected automatic braking
- Dash warning messages for FEB/AEB or front sensor
- System disables itself after warning
How to Fix
Scan the ADAS system for stored faults and verify radar/camera alignment, windshield condition, and front emblem/radar cleanliness. Infiniti service procedures typically involve checking for software updates, recalibrating the forward camera/radar, and replacing a faulty sensor only after alignment and aiming are confirmed. Owners should document the exact conditions when the event occurs to help reproduce the issue.
Owner tips & cautions
- TipAfter windshield replacement or front-end work, insist on proper ADAS calibration rather than assuming the system will self-learn.
Sources for this issue (1)
Nissan Murano · 2021–2024
Nissan NTB19-033G applies to 2015-2024 Murano Z52 vehicles when ICC stops working, the AEB/FEB warning illuminates, or a front-radar obstruction message appears and C1A16, C1A16-97, C2582 or C2582-97 is the only stored DTC. Its flow separates obstruction and weather from repeat incidents, sensor manufacture date, replacement where authorized and required sensor alignment. The frozen 2021-2024 page is inside that exact boundary.
Common Symptoms
- ICC inoperative or AEB/FEB warning documented
- front-radar obstruction message and conditions recorded
- C1A16/C2582-only path confirmed before hardware action
How to Fix
Preserve all DTCs and confirm whether obstruction or severe weather explains the event. Use NTB19-033G only when one listed radar DTC is the sole stored code; the bulletin repeatedly says not to replace the distance sensor outside its flow. When replacement is authorized, use the EPC for the VIN-specific sensor and perform alignment. Do not buy a radar sensor or bracket from this page; DTC state, manufacture date, diagnosis, calibration and VIN fitment must be established first.
Sources for this issue (2)
Nissan Sentra · 2023–2025
Nissan Titan · 2020–2024
Find C1A16 by make
Browse every documented model and issue for your make.
C1A16 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 C1A16 mean?
C1A16 stands for "Manufacturer-Specific Chassis Code (Nissan/Infiniti: Radar/Distance Sensor Obstruction or Misalignment)." C1A16 is a manufacturer-specific chassis code commonly seen on Nissan and Infiniti vehicles equipped with intelligent cruise control and forward-collision/automatic emergency braking, where it relates to the front radar/distance sensor being blocked, dirty, misaligned, or otherwise unable to function. The driver-assistance module monitors the radar and sets this code when the sensor's view is obstructed or its signal is unreliable, often disabling those safety features. Because it can disable collision-avoidance functions, it carries elevated importance. The exact definition should be confirmed against the specific vehicle.
What are the most common causes of C1A16?
The most common causes of C1A16 are: Obstructed radar sensor (snow, ice, mud, debris, emblem/badge), Misaligned or knocked sensor bracket (often after a minor impact), Damaged or faulty radar/distance sensor, Wiring or connector problems at the sensor, Aftermarket bumper covers or accessories blocking the sensor, Sensor not recalibrated after bumper/grille work, Driver-assistance control module fault. The specific cause varies by vehicle.
How much does it cost to fix C1A16?
Repair costs for C1A16 range from $200 to $1,800, depending on the vehicle and root cause.
Which vehicles are affected by C1A16?
Au7o has documented C1A16 across 5 vehicle models from 2 manufacturers: Infiniti, Nissan.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.