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Home >> Nissan-Datsun >> 2012 >> Altima Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Introduction) (Qr25DE For CALIFORNIA) >> 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
1 Ground L Tumble control valve motor (Close) Output [Ignition switch ON]
  • Engine coolant temperature: Between 5°C (41°F) and 60°C (140°F)
  • Accelerator pedal: Depressed → fully released
 Battery voltage appears for about 1 second.
2 Ground L Throttle control motor relay power supply Input [Ignition switch: ON] BATTERY VOLTAGE (11 - 14 V)
3 Ground G Tumble control valve motor (Open) Output [Ignition switch ON]
  • Engine coolant temperature: Between 5°C (41°F) and 60°C (140°F)
  • Accelerator pedal: Fully released → depressed
 Battery voltage appears for about 1 second.
4 Ground LG A/F sensor 1 heater Output [Engine is running]
  • Warm-up condition
  • Idle speed
 2.9 - 8.8 V(1)
G05867571
5 Ground BR Throttle control motor (Open) Output [Ignition switch: ON]
  • Engine stopped
  • Selector lever: D (CVT), 1st (M/T)
  • Accelerator pedal: Fully depressed
 0 - 14 V(1)
G05867572
6 Ground BR Throttle control motor (Close) Output [Ignition switch: ON]
  • Engine stopped
  • Selector lever: D (CVT), 1st (M/T)
  • Accelerator pedal: Fully released
 0 - 14 V(1)
G05696273
7 Ground V Tumble control valve motor power supply Input [Ignition switch: ON] BATTERY VOLTAGE
(11 - 14 V)
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 - 0.1 V(1)
G04887978
[Engine is running]
  • Warm-up condition
  • Engine speed: 2, 000 rpm
 0 - 0.2 V(1)
G05696275
12
16		 Ground GR 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
 10 V(1)
G05696276
[Ignition switch: ON]
  • Engine stopped

    [Engine is running]

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

[Engine is running]		 0 - 1.0 V
[Ignition switch: ON]
  • More than 1 second after turning ignition switch ON
 BATTERY VOLTAGE
(11 - 14 V)
15 Ground R Throttle control motor relay Output [Ignition switch: ON → OFF] 0 - 1.0 V
↓
BATTERY VOLTAGE
(11 - 14 V)
↓
0 V
[Ignition switch: ON] 0 - 1.0 V
17 Ground L Heated oxygen sensor 3 heater Output [Engine is running]
  • Engine speed: Below 3, 600 rpm after the following conditions are met

  • Engine: after warming up
  • Driving for 3 minutes at a speed of 80 km/h (50 MPH) or more

(Keep the vehicle speed as steady as possible during the cruising.)		 10 V(1)
G05696276
[Ignition switch: ON]
  • Engine stopped

    [Engine is running]

  • Engine speed: Above 3, 600 rpm
 BATTERY VOLTAGE
(11 - 14 V)
24 Ground SB ECM relay (Self shut-off) Output [Engine is running]
[Ignition switch: OFF]
  • A few seconds after turning ignition switch OFF
 0 - 1.0 V
[Ignition switch: OFF]
  • More than a few seconds after turning ignition switch OFF
 BATTERY VOLTAGE
(11 - 14 V)
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 - 14 V(1))
G05696278
[Engine is running]
  • Engine speed: About 2, 000 rpm (More than 100 seconds after starting engine.)
 BATTERY VOLTAGE
(11 - 14 V(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 - 14 V(1))
G05696280
[Engine is running]
  • Warm-up condition
  • Engine speed: 2, 000 rpm
 BATTERY VOLTAGE
(11 - 14 V(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 - 1.0 V
34 Ground W Heated oxygen sensor 3 Input [Engine is running]
  • Revving engine from idle to 3, 000 rpm quickly after the following conditions are met
    • Engine: after warming up
    • Driving for 3 minutes at a speed of 80 km/h (50 MPH) or more

    (Keep the vehicle speed as steady as possible during the cruising.)

 0 - 1.0 V
35 Ground B Sensor ground
(Heated oxygen sensor 2,
Heated oxygen sensor 3)		 - [Engine is running]
  • Warm-up condition
  • Idle speed
 0 V
36 Ground G Sensor ground
(Throttle position sensor)		 - [Engine is running]
  • Warm-up condition
  • Idle speed
 0 V
37 Ground B Throttle position sensor 1 Input [Ignition switch: ON]
  • Engine stopped
  • Selector lever: D (CVT), 1st (M/T)
  • Accelerator pedal: Fully released
 More than 0.36 V
[Ignition switch: ON]
  • Engine stopped
  • Selector lever: D (CVT), 1st (M/T)
  • Accelerator pedal: Fully depressed
 Less than 4.75 V
38 Ground R Throttle position sensor 2 Input [Ignition switch: ON]
  • Engine stopped
  • Selector lever: D (CVT), 1st (M/T)
  • Accelerator pedal: Fully released
 Less than 4.75 V
[Ignition switch: ON]
  • Engine stopped
  • Selector lever: D (CVT), 1st (M/T)
  • Accelerator pedal: Fully depressed
 More than 0.36 V
39 Ground R Refrigerant pressure sensor Input [Engine is running]
  • Warm-up condition
  • Both A/C switch and blower fan motor switch: ON (Compressor operates)
 1.0 - 4.0 V
40 Ground R Sensor ground
(Refrigerant pressure sensor)		 - [Engine is running]
  • Warm-up condition
  • Idle speed
 0 V
41 Ground SB Power steering pressure sensor Output [Engine is running]
  • Steering wheel: Being turned
 0.5 - 4.0 V
[Engine is running]
  • Steering wheel: Not being turned
 0.4 - 0.8 V
42 Ground Y Battery current sensor Input [Engine is running]
  • Battery: Fully charged*
  • Idle speed
 2.6 - 3.5 V
44 Ground B Sensor ground
(Battery current sensor)		 - [Engine is running]
  • Warm-up condition
  • Idle speed
 0 V
45 Ground G A/F sensor 1 (bank 1) Input [Ignition switch: ON] 2.2 V
46 Ground P Engine coolant temperature sensor Input [Engine is running] 0 - 4.8 V
Output voltage varies with engine coolant temperature.
47 Ground W Sensor power supply
(Throttle position sensor)		 - [Ignition switch: ON] 5 V
48 Ground G Sensor ground
(Power steering pressure sensor)		 - [Engine is running]
  • Warm-up condition
  • Idle speed
 0 V
49 Ground L A/F sensor 1 Input [Engine is running]
  • Warm-up condition
  • Engine speed: 2, 000 rpm
 1.8 V
Output voltage varies with air fuel ratio.
50 Ground O Intake air temperature sensor Input [Engine is running] 0 - 4.8 V
Output voltage varies with intake air temperature.
51 Ground BR Sensor power supply - [Ignition switch: ON] 5 V
52 Ground SB Sensor ground
(Tumble control valve position sensor, Engine coolant temperature sensor)		 - [Engine is running]
  • Warm-up condition
  • Idle speed
 0 V
54 Ground G Tumble control valve position sensor Input [Ignition switch ON]
  • Engine coolant temperature: Between 5°C (41°F) and 60°C (140°F)
  • Accelerator pedal: Fully released
 Less than 1.2 V
[Ignition switch ON]
  • Engine coolant temperature: Between 5°C (41°F) and 60°C (140°F)
  • Accelerator pedal: Slightly depressed
 More than 2.9 V
55 Ground Y Sensor power supply
(Power steering pressure sensor)		 - [Ignition switch: ON] 5 V
56 Ground R Sensor ground
(Mass air flow sensor, Intake air temperature sensor)		 - [Engine is running]
  • Warm-up condition
  • Idle speed
 0 V
58 Ground GR Mass air flow sensor Input [Engine is running]
  • Warm-up condition
  • Idle speed
 0.9 - 1.1 V
[Engine is running]
  • Warm-up condition
  • Engine speed: 2, 500 rpm
 1.4 - 1.7 V
59 Ground O Sensor power supply
[Camshaft position sensor (PHASE)]		 - [Ignition switch: ON] 5 V
60 Ground W Sensor ground
[Crankshaft position sensor (POS)]		 - [Engine is running]
  • Warm-up condition
  • Idle speed
 0 V
61 Ground W Knock sensor Input [Engine is running]
  • Idle speed
 2.5 V
64 Ground L Sensor ground
[Camshaft position sensor (PHASE)]		 - [Engine is running]
  • Warm-up condition
  • Idle speed
 0 V
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
 3.0 V(1)
G05696282
[Engine is running]
  • Engine speed: 2, 000 rpm
 3.0 V(1)
G05696283
67 Ground - Sensor ground
(Knock sensor)		 - [Engine is running]
  • Warm-up condition
  • Idle speed
 0 V
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
(Tumble control valve position sensor, Refrigerant pressure sensor)		 - [Ignition switch: ON] 5 V
76 Ground L Sensor power supply
[Crankshaft position sensor (POS)]		 - [Ignition switch: ON] 5 V
77 Ground LG Power supply for ECM (Back-up) Input [Ignition switch: OFF] BATTERY VOLTAGE
(11 - 14 V)
78 Ground P Intake valve timing control solenoid valve Output [Engine is running]
  • Warm-up condition
  • Idle speed
 0 V
[Engine is running]
  • Warm-up condition
  • Engine speed: 2, 000rpm
 7 - 10 V(1)
G05696286
81 Ground W Accelerator pedal position sensor 1 Input [Ignition switch: ON]
  • Engine stopped
  • Accelerator pedal: Fully released
 0.5 - 1.0 V
[Ignition switch: ON]
  • Engine stopped
  • Accelerator pedal: Fully depressed
 4.2 - 4.8 V
82 Ground O Accelerator pedal position sensor 2 Input [Ignition switch: ON]
  • Engine stopped
  • Accelerator pedal: Fully released
 0.25 - 0.5 V
[Ignition switch: ON]
  • Engine stopped
  • Accelerator pedal: Fully depressed
 2.0 - 2.5 V
83 Ground GR Sensor power supply
(Accelerator pedal position sensor 1)		 - [Ignition switch: ON] 5 V
84 Ground B Sensor ground
(Accelerator pedal position sensor 1)		 - [Engine is running]
  • Warm-up condition
  • Idle speed
 0 V
85 Ground Y ASCD steering switch Input [Ignition switch: ON]
  • ASCD steering switch: OFF
 4 V
[Ignition switch: ON]
  • MAIN switch: Pressed
 0 V
[Ignition switch: ON]
  • CANCEL switch: Pressed
 1 V
[Ignition switch: ON]
  • RESUME/ACCELERATE switch: Pressed
 3 V
[Ignition switch: ON]
  • SET/COAST switch: Pressed
 2 V
86 Ground SB EVAP control system pressure sensor Input [Ignition switch: ON] 1.8 - 4.8 V
87 Ground BR Sensor power supply
(Accelerator pedal position sensor 2)		 - [Ignition switch: ON] 5 V
88 - O Data link connector Input/Output - -
91 Ground V Sensor power supply
(EVAP control system pressure sensor)		 - [Ignition switch: ON] 5 V
92 Ground BR Sensor ground
(ASCD steering switch)		 - [Engine is running]
  • Warm-up condition
  • Idle speed
 0 V
93 Ground Y Ignition switch Input [Ignition switch: OFF] 0 V
[Ignition switch: ON] BATTERY VOLTAGE
(11 - 14 V)
94 - GR Engine speed signal output Output - -
95 Ground Y Fuel tank temperature sensor Input [Engine is running] 0 - 4.8 V
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
 0 V
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
 0 V
102 Ground R PNP signal Input [Ignition switch: ON]
  • Selector lever: P or N (CVT), Neutral (M/T)
 BATTERY VOLTAGE
(11 - 14 V)
[Ignition switch: ON]
  • Selector lever: Except above
 0 V
104 Ground P Sensor ground
(Fuel tank temperature sensor)		 - [Engine is running]
  • Warm-up condition
  • Idle speed
 0 V
105 Ground V Power supply for ECM Input [Ignition switch: ON] BATTERY VOLTAGE
(11 - 14 V)
106 Ground SB Stop lamp switch Input [Ignition switch: OFF]
  • Brake pedal: Fully released
 0 V
[Ignition switch: OFF]
  • Brake pedal: Slightly depressed
 BATTERY VOLTAGE
(11 - 14 V)
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 - 14 V)
110 Ground G ASCD brake switch Input [Ignition switch: ON]
  • Brake pedal: Slightly depressed (CVT)
  • Brake pedal and clutch pedal: Slightly depressed (M/T)
 0 V
[Ignition switch: ON]
  • Brake pedal: Fully released (CVT)
  • Brake pedal and/or clutch pedal: Fully released (M/T)
 BATTERY VOLTAGE
(11 - 14 V)
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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