Nissan Altima 2007-2012 Service Manual: B2557 vehicle speed
Description
BCM receives the 2 vehicle speed signals via CAN communication. One signal is transmitted by the “unified meter”. Another signal is transmitted by “ABS actuator and electric unit (control unit)”. BCM compares both signals to detect the vehicle speed.
DTC Logic
DTC DETECTION LOGIC
NOTE: • If DTC B2557 is displayed with DTC U1000, first perform the trouble diagnosis for DTC U1000. Refer to SEC-235, "DTC Logic".
• If DTC B2557 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010. Refer to SEC-236, "DTC Logic".
DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION PROCEDURE
1. Drive the vehicle at the vehicle speed of 10 km/h or more and wait for at least 10 seconds.
2. Check “Self Diagnostic Result” with CONSULT-III.
Is DTC detected? YES >> Refer to SEC-273, "Diagnosis Procedure".
NO >> Inspection End.
Diagnosis Procedure
1.CHECK DTC WITH “ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)”
Check “Self Diagnostic Result” with CONSULT-III. Refer to BRC-51, "DTC No. Index".
Is the inspection result normal? YES >> GO TO 2
NO >> Repair or replace malfunctioning parts.
2.CHECK UNIFIED METER.
Check unified meter. Refer to MWI-4, "Work Flow".
>> Inspection End.
B2556 push-button ignition switch
Description
The switch that changes the power supply position. BCM maintains the power
supply position status. BCM
changes the power supply position with the operation of the push-button ignition ...
B2560 starter control relay
Description
Starter control relay, integrated in IPDM E/R, permits the starter relay
operation when in N or P position and
the steering is locked or unlocked. It is installed in parallel with the ...
Other materials:
P1421 cold start control
Description
ECM controls ignition timing and engine idle speed when engine is started
with prewarming up condition.
This control promotes the activation of three way catalyst by heating the
catalyst and reduces emissions.
DTC Logic
DTC DETECTION LOGIC
NOTE:
If DTC P1421 is displayed wit ...
P2118 throttle control motor
Description
The throttle control motor is operated by the ECM and it opens and closes the
throttle valve.
The current opening angle of the throttle valve is detected by the throttle
position sensor and it provides feedback
to the ECM to control the throttle control motor to make the throttl ...
Precautions on cruise control
1. CANCEL switch
2. ACCEL/RES switch
3. COAST/SET switch
4. ON/OFF switch
● If the cruise control system malfunctions, it
cancels automatically. The SET indicator
light in the instrument panel then blinks to
warn the driver.
● If the SET indicator light blinks, turn the
cruise ...