DTC Detection Logic

WARNING: This page is about a different car, the 2020 Infiniti QX60. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

If DTC is displayed along with DTC U1000, first perform the trouble diagnosis for DTC U1000. Refer to DTC Logic .
If DTC is displayed along with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer to DTC Logic .

DTC

Items

(CONSULT screen terms)

DTC detection condition

Possible cause

B257B

AMBIENT SENSOR

The ambient sensor recognition temperature is too high.

Ambient sensor
A/C auto amp.
Harness or connectors
(The sensor circuit is open or shorted.)

B257C

The ambient sensor recognition temperature is too low.