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Home >> Nissan-Datsun >> 2012 >> Altima Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Introduction) (Qr25DE For MEXICO) >> Ecu Diagnosis Information >> ECM >> Reference Value >> Physical Values
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Physical Values

NOTE:
  • ECM is located in the engine room left side near battery.
  • Specification data are reference values and are measured between each terminal and ground.
  • Pulse signal is measured by CONSULT.
CAUTION: Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in damage to the ECMs transistor. Use a ground other than ECM terminals, such as the ground.
Terminal No. Wire color Description Condition Value (Approx.)
+ - Signal name Input/Output
2 Ground L Throttle control motor relay power supply Input [Ignition switch: ON] BATTERY VOLTAGE (11 - 14V)
4 Ground LG A/F sensor 1 heater Output [Engine is running]
  • Warm-up condition
  • Idle speed
 2.9 - 8.8V(1)
G05867571
5 Ground GR Throttle control motor (Open) Output [Ignition switch: ON]
  • Engine stopped
  • Shift lever: D
  • Accelerator pedal: Fully depressed
 0 - 14V(1)
G05867572
6 Ground BR Throttle control motor (Close) Output [Ignition switch: ON]
  • Engine stopped
  • Shift lever: D
  • Accelerator pedal: Fully released
 0 - 14V(1)
G05696273
9
10
11
21		 Ground O
LG
Y
BR		 Ignition signal No. 3
Ignition signal No. 2
Ignition signal No. 1
Ignition signal No. 4		 Output [Engine is running]
  • Warm-up condition
  • Idle speed
NOTE: The pulse cycle changes depending on rpm at idle
 0 - 0.1V(1)
G04887978
[Engine is running]
  • Warm-up condition
  • Engine speed: 2, 000 rpm
 0 - 0.2V(1)
G05696275
12
16		 Ground B ECM ground - [Engine is running]
  • Idle speed
 Body ground
13 Ground Y Heated oxygen sensor 2 heater Output [Engine is running]
  • Engine speed: Below 3, 600 rpm after the following conditions are met

  • Engine: after warming up
  • Keeping the engine speed between 3, 500 and 4, 000 rpm for 1 minute and at idle for 1 minute under no load
 10V(1)
G05733549
[Ignition switch: ON]
  • Engine stopped

[Engine is running]
  • Engine speed: Above 3, 600 rpm
 BATTERY VOLTAGE (11 - 14V)
14 Ground B/R Fuel pump relay Output [Ignition switch: ON]
  • For 1 second after turning ignition switch ON

[Engine is running]		 0 - 1.0V
[Ignition switch ON]
  • More than 1 second after turning ignition switch ON
 BATTERY VOLTAGE (11 - 14V)
15 Ground R Throttle control motor relay Output [Ignition switch: ON → OFF] 0 - 1.0V
↓
BATTERY VOLTAGE (11 - 14V)
↓
0V
[Ignition switch: ON] 0 - 1.0V
24 Ground SB ECM relay (Self shut-off) Output [Engine is running]
[Ignition switch: OFF]
  • A few seconds after turning ignition switch OFF
 0 - 1.0V
[Ignition switch: OFF]
  • More than a few seconds after turning ignition switch OFF
 BATTERY VOLTAGE (11 - 14V)
25 Ground P EVAP canister purge volume control solenoid valve Output [Engine is running]
  • Idle speed
  • Accelerator pedal: Not depressed even slightly, after engine starting
 BATTERY VOLTAGE (11 - 14V)(1)
G05696278
[Engine is running]
  • Engine speed: About 2, 000 rpm (More than 100 seconds after starting engine.)
 BATTERY VOLTAGE (11 - 14V)(1)
G05696279
29
30
31
32		 Ground LG
W
O
V		 Fuel injector No. 4
Fuel injector No. 3
Fuel injector No. 2
Fuel injector No. 1		 Output [Engine is running]
  • Warm-up condition
  • Idle speed
NOTE: The pulse cycle changes depending on rpm at idle
 BATTERY VOLTAGE (11 - 14V)(1)
G05696280
[Engine is running]
  • Warm-up condition
  • Engine speed: 2, 000 rpm
 BATTERY VOLTAGE (11 - 14V)(1)
G05696281
33 Ground BR Heated oxygen sensor 2 Input [Engine is running]
  • Revving engine from idle to 3, 000 rpm quickly after the following conditions are met

  • Engine: after warming up
  • Keeping the engine speed between 3, 500 and 4, 000 rpm for 1 minute and at idle for 1 minute under no load
 0 - 1.0V
35 Ground B Sensor ground
(Heated oxygen sensor 2)		 - [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
36 Ground G Sensor ground (Throttle position sensor) - [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
37 Ground B Throttle position sensor 1 Input [Ignition switch: ON]
  • Engine stopped
  • Shift lever: D
  • Accelerator pedal: Fully released
 More than 0.36V
[Ignition switch: ON]
  • Engine stopped
  • Shift lever: D
  • Accelerator pedal: Fully depressed
 Less than 4.75V
38 Ground R Throttle position sensor 2 Input [Ignition switch: ON]
  • Engine stopped
  • Shift lever: D
  • Accelerator pedal: Fully released
 Less than 4.75V
[Ignition switch: ON]
  • Engine stopped
  • Shift lever: D
  • Accelerator pedal: Fully depressed
 More than 0.36V
39 Ground L Refrigerant pressure sensor Input [Engine is running]
  • Warm-up condition
  • Both A/C switch and blower fan motor switch: ON (Compressor operates)
 1.0 - 4.0V
40 Ground GR Sensor ground (Refrigerant pressure sensor) - [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
41 Ground SB Power steering pressure sensor Output [Engine is running]
  • Steering wheel: Being turned
 0.5 - 4.0V
[Engine is running]
  • Steering wheel: Not being turned
 0.4 - 0.8V
42 Ground Y Battery current sensor Input [Engine is running]
  • Battery: Fully charged*
  • Idle speed
 2.6 - 3.5V
44 Ground B Sensor ground (Battery current sensor) - [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
45 Ground G A/F sensor 1 (bank 1) Input [Ignition switch: ON] 2.2V
46 Ground P Engine coolant temperature sensor Input [Engine is running] 0 - 4.8V
Output voltage varies with engine coolant temperature.
47 Ground W Sensor power supply (Throttle position sensor) - [Ignition switch: ON] 5V
48 Ground LG Sensor ground (Power steering pressure sensor) - [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
49 Ground L A/F sensor 1 Input [Engine is running]
  • Warm-up condition
  • Engine speed: 2, 000 rpm
 1.8V
Output voltage varies with air fuel ratio.
50 Ground O Intake air temperature sensor Input [Engine is running] 0 - 4.8V
Output voltage varies with intake air temperature.
51 Ground BR Sensor power supply - [Ignition switch: ON] 5V
52 Ground SB Sensor ground (Engine coolant temperature sensor) - [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
55 Ground Y Sensor power supply (Power steering pressure sensor) - [Ignition switch: ON] 5V
56 Ground R Sensor ground (Mass air flow sensor, Intake air temperature sensor) - [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
58 Ground GR Mass air flow sensor Input [Engine is running]
  • Warm-up condition
  • Idle speed
 0.9 - 1.1V
[Engine is running]
  • Warm-up condition
  • Engine speed: 2, 500 rpm
 1.4 - 1.7V
59 Ground O Sensor power supply [Camshaft position sensor (PHASE)] - [Ignition switch: ON] 5V
60 Ground W Sensor ground [Crankshaft position sensor (POS)] - [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
61 Ground W Knock sensor Input [Engine is running]
  • Idle speed
 2.5V
64 Ground L Sensor ground [Camshaft position sensor (PHASE)] - [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
65 Ground R Crankshaft position sensor (POS) Input [Engine is running]
  • Warm-up condition
  • Idle speed
NOTE: The pulse cycle changes depending on rpm at idle
 3.0V(1)
G05696282
[Engine is running]
  • Engine speed: 2, 000 rpm
 3.0V(1)
G05696283
67 Ground - Sensor ground (Knock sensor) - [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
69 Ground Y Camshaft position sensor (PHASE) Input [Engine is running]
  • Warm-up condition
  • Idle speed
NOTE: The pulse cycle changes depending on rpm at idle
 1.0 - 4.0(1)
G05696284
[Engine is running]
  • Engine speed is 2, 000 rpm
 1.0 - 4.0(1)
G05696285
72 Ground V Sensor power supply (Refrigerant pressure sensor) - [Ignition switch: ON] 5V
76 Ground L Sensor power supply [Crankshaft position sensor (POS)] - [Ignition switch: ON] 5V
77 Ground LG Power supply for ECM (Back-up) Input [Ignition switch: OFF] BATTERY VOLTAGE (11 - 14V)
78 Ground P Intake valve timing control solenoid valve Output [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
[Engine is running]
  • Warm-up condition
  • Engine speed: 2, 000 rpm
 7 - 10V(1)
G05696286
81 Ground W Accelerator pedal position sensor 1 Input [Ignition switch: ON]
  • Engine stopped
  • Accelerator pedal: Fully released
 0.5 - 1.0V
[Ignition switch: ON]
  • Engine stopped
  • Accelerator pedal: Fully depressed
 4.2 - 4.8V
82 Ground O Accelerator pedal position sensor 2 Input [Ignition switch: ON]
  • Engine stopped
  • Accelerator pedal: Fully released
 0.25 - 0.5V
[Ignition switch: ON]
  • Engine stopped
  • Accelerator pedal: Fully depressed
 2.0 - 2.5V
83 Ground GR Sensor power supply (Accelerator pedal position sensor 1) - [Ignition switch: ON] 5V
84 Ground B Sensor ground (Accelerator pedal position sensor 1) - [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
85 Ground Y ASCD steering switch Input [Ignition switch: ON]
  • ASCD steering switch: OFF
 4V
[Ignition switch: ON]
  • MAIN switch: Pressed
 0V
[Ignition switch: ON]
  • CANCEL switch: Pressed
 1V
[Ignition switch: ON]
  • RESUME/ACCELERATE switch: Pressed
 3V
[Ignition switch: ON]
  • SET/COAST switch: Pressed
 2V
86 Ground SB EVAP control system pressure sensor Input [Ignition switch: ON] 1.8 - 4.8V
87 Ground BR Sensor power supply (Accelerator pedal position sensor 2) - [Ignition switch: ON] 5V
88 - O Data link connector Input/Output - -
91 Ground V Sensor power supply (EVAP control system pressure sensor) - [Ignition switch: ON] 5V
92 Ground BR Sensor ground (ASCD steering switch) - [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
93 Ground Y Ignition switch Input [Ignition switch: OFF] 0V
[Ignition switch: ON] BATTERY VOLTAGE (11 - 14V)
94 - GR Engine speed signal output Output - -
95 Ground Y Fuel tank temperature sensor Input [Engine is running] 0 - 4.8V
Output voltage varies with fuel tank temperature.
96 Ground GR Sensor ground (EVAP control system pressure sensor) - [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
97 - P CAN communication line Input/Output - -
98 - L CAN communication line Input/Output - -
100 Ground G Sensor ground (Accelerator pedal position sensor 2) - [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
102 Ground R PNP signal Input [Ignition switch: ON]
  • Shift lever: P or N
 BATTERY VOLTAGE (11 - 14V)
[Ignition switch: ON]
  • Shift lever: Except above
 0V
104 Ground P Sensor ground (Fuel tank temperature sensor) - [Engine is running]
  • Warm-up condition
  • Idle speed
 0V
105 Ground V Power supply for ECM Input [Ignition switch: ON] BATTERY VOLTAGE (11 - 14V)
106 Ground SB Stop lamp switch Input [Ignition switch: OFF]
  • Brake pedal: Fully released
 0V
[Ignition switch: OFF]
  • Brake pedal: Slightly depressed
 BATTERY VOLTAGE (11 - 14V)
107
108		 Ground B ECM ground - [Engine is running]
  • Idle speed
 Body ground
109 Ground W EVAP canister vent control valve Output [Ignition switch: ON] BATTERY VOLTAGE (11 - 14V)
110 Ground G ASCD brake switch Input [Ignition switch: ON]
  • Brake pedal: Slightly depressed
 0V
[Ignition switch: ON]
  • Brake pedal: Fully released
 BATTERY VOLTAGE (11 - 14V)
111
112		 Ground B ECM ground - [Engine is running]
  • Idle speed
 Body ground
(1) Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
(2) Before measuring the terminal voltage, confirm that the battery is fully charged. Refer to "HOW TO HANDLE BATTERY ".
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