Nissan Altima 2007-2012 Service Manual: P0603 ECM Power supply
Description
Battery voltage is supplied to the ECM even when the ignition switch is turned OFF for the ECM memory function of the DTC memory, the air-fuel ratio feedback compensation value memory, the idle air volume learning value memory, etc.
DTC Logic
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next test.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON and wait at least 1 second.
2. Start engine and let it idle for 1 second.
3. Turn ignition switch OFF, wait at least 10 seconds, and then turn it ON.
4. Repeat steps 2 and 3 for 4 times.
5. Check 1st trip DTC.
Is 1st trip DTC detected? YES >> Go to EC-1374, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
1.CHECK ECM POWER SUPPLY
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check the voltage between ECM harness connector and ground.
Is the inspection result normal? YES >> GO TO 3.
NO >> GO TO 2.
2.DETECT MALFUNCTIONING PART
Check the following.
• 15 A fuse (No. 42) • IPDM E/R harness connector F10
• Harness for open or short between ECM and battery
>> Repair or replace harness or connectors.
3.CHECK INTERMITTENT INCIDENT
Refer to GI-42, "Intermittent Incident".
Is the inspection result normal? YES >> GO TO 4.
NO >> Repair or replace harness or connectors.
4.PERFORM DTC CONFIRMATION PROCEDURE
1. Turn ignition switch ON.
2. Erase DTC.
3. Perform DTC CONFIRMATION PROCEDURE.
See EC-1374, "DTC Logic".
Is the 1st trip DTC P0603 displayed again? YES >> GO TO 5.
NO >> INSPECTION END
5.REPLACE ECM
1. Replace ECM.
2. Go to EC-1051, "ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT : Special Repair Requirement".
>> INSPECTION END
P0550 PSP Sensor
Description
Power steering pressure (PSP) sensor is installed to the power steering
high-pressure tube and detects a
power steering load.
This sensor is a potentiometer which transforms the pow ...
P0605 ECM
Description
The ECM consists of a microcomputer and connectors for signal
input and output and for power supply. The ECM controls the engine.
DTC Logic
DTC DETECTION LOGIC
DTC CONFIRMATION PR ...
Other materials:
U120C DVD-ROM mecha detect
Description
Refer to AV-240, "System Description".
DTC Logic
DTC DETECTION LOGIC
Diagnosis Procedure
1.CHECK DVD-ROM
Check DVD-ROM for dirt, scratches and warpage.
Is the DVD-ROM clean and undamaged?
YES >> Replace AV control unit. Refer to AV-437, "Removal and I ...
On-vehicle repair
ACCELERATOR CONTROL SYSTEM
Exploded View
1. Accelerator pedal and accelerator
position sensor assembly.
2. Locating pins
Removal and Installation
REMOVAL
1. Disconnect the battery negative terminal.
2. Disconnect the accelerator position sensor electrical connector.
3. Remove the t ...
Power control system
System Diagram
System Description
COOLING FAN CONTROL
IPDM E/R controls cooling fans according to the status of the cooling fan
speed request signal received from
ECM via CAN communication. Refer to LAN-7, "System Description".
GENERATOR CONTROL
IPDM E/R outputs power generation ...