C1A16 on Nissan: How to Diagnose & Fix
Manufacturer-Specific Chassis Code (Nissan/Infiniti: Radar/Distance Sensor Obstruction or Misalignment)
3 Nissan models · 3 documented issues · 3 critical · $250-$1,800 repair
C1A16 on Nissan by model: symptoms, diagnosis and fix
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.
Sources for this issue (1)
Nissan bulletin NTB19-033G covers intelligent cruise control (ICC) cutting out, an AEB/FEB warning or a radar-obstruction message on the 2023 Murano when one of these radar codes is the only stored trouble code: C1A16, C1A16-97, C2582 or C2582-97. The warning does not by itself mean the sensor has failed. This is a service bulletin, not a recall. The bulletin's sensor replacement steps based on the sensor's build date cover only 2015–2018 Muranos, not the 2023 model.
Common Symptoms
- Cruise control (ICC) cuts out
- AEB/FEB warning
- Radar-obstruction message
How to Fix
Have a Nissan technician save the stored fault information and check whether something is blocking the radar or weather is the cause. On a 2023 Murano, the technician should diagnose further using the service manual rather than replacing the sensor based on its build date. Do not buy a replacement sensor before the cause is confirmed.
Call to confirm they can assess your vehicle and perform the stated work. Search results do not confirm qualification, eligibility or coverage.
Sources for this issue (1)
Multiple owners of the current B18-generation Sentra report the Forward Collision Warning and Automatic Emergency Braking systems triggering warnings or braking unexpectedly, sometimes with no vehicle or obstacle present. This is a safety-critical issue because false braking or loss of collision mitigation can increase crash risk in traffic.
Common Symptoms
- Automatic emergency braking activates unexpectedly
- Warning chime with no obstacle ahead
How to Fix
Scan the ADAS system for stored faults, inspect the front radar sensor mounting and alignment, and check for contamination, impact damage, or harness issues. Owners should also verify that any applicable software updates or service campaigns have been completed.
Owner tips & cautions
- TipKeep the front radar area clean and inspect for minor bumper damage or misalignment after even light impacts; many owners report intermittent faults after parking-lot contact.
Sources for this issue (3)
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 on a Nissan?
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. On Nissan it is documented across 3 models: Rogue, Murano, Sentra.
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 on a Nissan?
Published repair estimates on Nissan range from $250 to $1,800 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.
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Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.