Nissan Altima (L32) 2007-2012 Service Manual: BCM branch line circuit
Diagnosis Procedure
INSPECTION PROCEDURE
1.CHECK CONNECTOR
1. Turn the ignition switch OFF.
2. Disconnect the battery cable from the negative terminal.
3. Check the terminals and connectors of the BCM for damage, bend and loose connection (unit side and connector side).
Is the inspection result normal? YES >> GO TO 2.
NO >> Repair the terminal and connector.
2.CHECK HARNESS FOR OPEN CIRCUIT
1. Disconnect the connector of BCM.
2. Check the resistance between the BCM harness connector terminals.
Is the measurement value within the specification? YES >> GO TO 3.
NO >> Repair the BCM branch line.
3.CHECK POWER SUPPLY AND GROUND CIRCUIT
Check the power supply and the ground circuit of the BCM. Refer to BCS-42, "Diagnosis Procedure".
Is the inspection result normal? YES (Present error)>>Replace the BCM. Refer to BCS-96, "Removal and Installation".
YES (Past error)>>Error was detected in the BCM branch line.
NO >> Repair the power supply and the ground circuit.
A-BAG branch line circuit
Diagnosis Procedure
1.CHECK AIR BAG DIAGNOSIS SENSOR UNIT
Check the air bag diagnosis sensor unit. Refer to SRC-3, "Work Flow".
Is the inspection result normal?
YES >> Replace t ...
DLC branch line circuit
Diagnosis Procedure
INSPECTION PROCEDURE
1.CHECK CONNECTOR
1. Turn the ignition switch OFF.
2. Disconnect the battery cable from the negative terminal.
3. Check the terminals and connectors o ...
Other materials:
Combination switch output circuit
Diagnosis Procedure
1. CHECK OUTPUT 1 - 5 SYSTEM CIRCUIT FOR OPEN
1. Turn the ignition switch OFF.
2. Disconnect the BCM and combination switch.
3. Check continuity between BCM harness connector and combination
switch harness connector.
Does continuity exist?
YES >> GO TO 2
NO ...
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 ...
Main line between DLC and ABS circuit
Diagnosis Procedure
INSPECTION PROCEDURE
1.CHECK CONNECTOR
1. Turn the ignition switch OFF.
2. Disconnect the battery cable from the negative terminal.
3. Check the following terminals and connectors for damage, bend and loose
connection (connector side
and harness side).
- Harness co ...
