Nissan Altima 2007-2012 Service Manual: P0506 ISC System
Description
The ECM controls the engine idle speed to a specified level through the fine adjustment of the air, which is let into the intake manifold, by operating the electric throttle control actuator. The operating of the throttle valve is varied to allow for optimum control of the engine idling speed. The crankshaft position sensor (POS) detects the actual engine speed and sends a signal to the ECM.
The ECM controls the electric throttle control actuator so that the engine speed coincides with the target value memorized in the ECM. The target engine speed is the lowest speed at which the engine can operate steadily.
The optimum value stored in the ECM is determined by taking into consideration various engine conditions, such as during warming up, deceleration, and engine load (air conditioner, power steering and cooling fan operation, etc.).
DTC Logic
DTC DETECTION LOGIC
NOTE: If DTC P0506 is displayed with other DTC, first perform the trouble diagnosis for the other DTC.
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.
If the target idle speed is out of the specified value, perform EC-30, "IDLE AIR VOLUME LEARNING : Special Repair Requirement", before conducting DTC Confirmation Procedure.
TESTING CONDITION: • Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
• Always perform the test at a temperature above −10°C(14°F).
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Start engine and run it for at least 1 minute at idle speed.
4. Check 1st trip DTC.
Is 1st trip DTC detected? YES >> Go to EC-350, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
1.CHECK INTAKE AIR LEAK
1. Start engine and let it idle.
2. Listen for an intake air leak after the mass air flow sensor.
Is intake air leak detected? YES >> Discover air leak location and repair.
NO >> GO TO 2.
2.REPLACE ECM
1. Stop engine.
2. Replace ECM.
3. Go to EC-27, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT : Special Repair Requirement".
>> INSPECTION END
P0500 VSS
Description
The vehicle speed signal is sent to the combination meter from the “ABS
actuator and electric unit (control
unit)” by CAN communication line. The combination meter then sends a si ...
P0507 ISC System
Description
The ECM controls the engine idle speed to a specified level through the fine
adjustment of the air, which is let
into the intake manifold, by operating the electric throttle control a ...
Other materials:
Can communication circuit
Diagnosis Procedure
INSPECTION PROCEDURE
1.CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the battery cable from the negative terminal.
3. Disconnect all the unit connectors on CAN communication system.
4. Check terminals and connectors for damage, bend and loose con ...
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 of the data link connector for damage,
bend and loose connection
(connector side and harness side) ...
Precautions in repairing high
strength steel
High Strength Steel (HSS)
High strength steel is used for body panels in order to reduce vehicle
weight.
Accordingly, precautions in repairing automotive bodies made of high strength
steel are described below:
SP130 is the most commonly used HSS.
Read the following precautions when re ...