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Nissan C1B84-00

(DIST SEN MALFUNCTION)  C1A17-49 – (CONTROL UNIT (INTERNAL ELECTRONIC ERROR)) Figure 1 ACTION 1. Install the new Distance Sensor. 2. Add a foam strip to th e new Distance Sensor

Common search variants: C1B8400 · C1B84 00 · C1B84_00 · Search ignores case and common separators.

DriveNot yet established by verified evidence.
ChargeNot yet established by verified evidence.
ServiceService is appropriate because Nissan published a specific repair procedure for the listed warning-light condition and DTC combination. Provide the technician with DTCs C1B84-00 and C1A17-49 and reference Nissan bulletin NTB18-057c.
Confidence95%

Quick answer

For a 2018 Nissan LEAF (ZE1) in the US, Nissan bulletin NTB18-057c applies when Malfunction and Automatic Emergency Braking (AEB) warning lights are on with DTC C1B84-00 and C1A17-49. The bulletin directs replacement of the Distance Sensor, addition of a foam strip, and radar alignment.

This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.

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1. What does C1B84-00 mean?

For a 2018 Nissan LEAF (ZE1) in the US, Nissan bulletin NTB18-057c applies when Malfunction and Automatic Emergency Braking (AEB) warning lights are on with DTC C1B84-00 and C1A17-49. The bulletin directs replacement of the Distance Sensor, addition of a foam strip, and radar alignment.

2. Technical explanation

C1B84-00 is identified in the supplied Nissan/NHTSA bulletin as “DIST SEN MALFUNCTION.” The same bulletin condition includes C1A17-49, identified as “CONTROL UNIT (INTERNAL ELECTRONIC ERROR).” Nissan’s documented corrective action is to install a new Distance Sensor, add a foam strip to the new sensor, and perform radar alignment. The bulletin states that the complete procedure must be followed.

3. What system is affected?

Distance Sensor and Automatic Emergency Braking (AEB) warning system. A more specific system designation is not yet established by verified evidence.

4. How serious is this code?

Not yet established by verified evidence.

5. Symptoms you may notice

  • Malfunction warning light is on.
  • Automatic Emergency Braking (AEB) warning light is on.
  • DTC C1B84-00 is present with DTC C1A17-49.

6. Possible causes

  • The verified bulletin identifies C1B84-00 as a Distance Sensor malfunction and C1A17-49 as a control-unit internal electronic error. A root cause beyond these code descriptions is not yet established by verified evidence.

7. Can I still drive the vehicle?

Not yet established by verified evidence.

8. Can I charge the vehicle?

Not yet established by verified evidence.

9. What you can safely do

  • Arrange diagnosis and repair by a Nissan dealer or qualified service facility using the complete Nissan bulletin procedure.
  • Do not attempt radar alignment without the required service procedure and equipment.

10. Step-by-step troubleshooting

  1. Confirm whether the Malfunction and AEB warning lights are on and whether both C1B84-00 and C1A17-49 are stored.
  2. Refer the vehicle to a qualified technician to follow the complete procedure in Nissan bulletin NTB18-057c.

11. When to contact service

Service is appropriate because Nissan published a specific repair procedure for the listed warning-light condition and DTC combination. Provide the technician with DTCs C1B84-00 and C1A17-49 and reference Nissan bulletin NTB18-057c.

12. What the service center may check

  • Confirm the documented condition: Malfunction and AEB warning lights on with C1B84-00 and C1A17-49.
  • Follow the complete Nissan NTB18-057c procedure.
  • Perform radar alignment after the documented sensor replacement and foam-strip installation.

13. Possible repair or resolution

  • Install a new Distance Sensor.
  • Add a foam strip to the new Distance Sensor.
  • Perform radar alignment.

14. Affected vehicles

15. Related TSBs / service bulletins

  • Nissan NTB18-057c, dated February 3, 2021: 2018 LEAF; Malfunction and AEB warning lights on. NHTSA manufacturer communication 10188306: https://static.nhtsa.gov/odi/tsbs/2021/MC-10188306-0001.pdf
  • Nissan NTB18-057b, dated January 18, 2019. NHTSA manufacturer communication 10153009: https://static.nhtsa.gov/odi/tsbs/2019/MC-10153009-9999.pdf
  • Nissan NTB18-057a, dated August 17, 2018. NHTSA manufacturer communication 10144521: https://static.nhtsa.gov/odi/tsbs/2018/MC-10144521-9999.pdf
  • Nissan NTB18-057, dated August 7, 2018. NHTSA manufacturer communication 10144520: https://static.nhtsa.gov/odi/tsbs/2018/MC-10144520-9999.pdf

16. Recall information

  • Not yet established by verified evidence.

17. Official manufacturer information

Verified official information: Nissan/NHTSA manufacturer communication NTB18-057c, applicable to the 2018 Nissan LEAF (ZE1) in the US under the documented condition. https://static.nhtsa.gov/odi/tsbs/2021/MC-10188306-0001.pdf

19. Frequently asked questions

What does C1B84-00 mean?

The verified Nissan bulletin identifies C1B84-00 as “DIST SEN MALFUNCTION.”

Which vehicle is covered by the verified bulletin?

The supplied applicability evidence identifies the 2018 Nissan LEAF (ZE1) in the US.

What warning lights are documented?

The bulletin documents Malfunction and AEB warning lights on.

What repair does Nissan specify?

Install a new Distance Sensor, add a foam strip to the new sensor, and perform radar alignment, following the complete bulletin procedure.

Is this a recall?

Not yet established by verified evidence.

Can I continue driving or charging?

Not yet established by verified evidence.

20. Sources & verification

Verified
Nissan C1B84-00: (DIST SEN MALFUNCTION)  C1A17-49 – (CONTROL UNIT… | EV Diagnostics