CHECK AT THE ENGINE-ECU TERMINALS



TERMINAL VOLTAGE CHECK CHART


warning A high-tension voltage is flowing between the engine-ECU and the injectors while the engine is running. Handle them carefully to avoid receiving electric shocks from the voltage.
1.Disconnect the engine-ECU connectors, and connect check harness special tool MB992291 between the engine-ECU connectors.
2.Measure the voltage between each check harness connector terminal and check harness connector earth terminal (GNDB, GNDE or SGND).
3.Connect a needle-nosed wire probe to a voltmeter probe.
4.Referring to the check sheet, insert the micromini probe into the check harness connector and measure the voltage.
note
  1. You may find it convenient to pull out the engine-ECU to make it easier to reach the connector terminals.
  2. The chart procedures do not have the particular order.
caution Short-circuiting the positive (+) probe between a connector terminal and earth could damage the vehicle wiring, the sensor, engine-ECU or all of them. Be careful to prevent this!
5.If voltmeter shows any deviation from standard value, check the corresponding sensor, actuator and related electrical wiring, then repair or replace.
6.After repair or replacement, recheck with the voltmeter to confirm that the repair has corrected the problem.
Engine-ECU Connector Terminal Arrangement

Terminal No.
Terminal code
Check item
Inspection condition (engine status)
Normal condition:
7
ALTL
Alternator L terminal
Ignition switch: ON
0.5 - 2.0 V
Engine: Idle operation
System voltage
8
NTSW
Starter active signal
Engine: Cranking
System voltage
Engine: Idle operation
1 V or less
10
WLS
Water level switch
Ignition switch: ON
Water level in the fuel filter: Lower than the standard value (approximately 105 ml or less)
1 V or less
Water level in the fuel filter: Higher than the standard value (approximately 105 ml or more)
System voltage
13
OPSW
Engine oil pressure switch
Ignition switch: ON
1 V or less
Engine: Idle operation
System voltage
17
VGT
Variable geometry control solenoid valve
Ignition switch: ON
System voltage
Engine: Acceleration
Voltage changes in accordance with amount of depression of accelerator pedal
18
STRL
Starter relay (Vehicles without AS&G system)
Engine: Cranking
System voltage
Engine: Idle operation
1 V or less
19
AC/R
A/C compressor relay
Engine: Idle operation
A/C switch: OFF
System voltage
A/C switch: ON (A/C compressor in operation)
1 V or less
23
EGC
EGR cooler bypass control solenoid valve
Engine: Idle operation
Engine coolant temperature: Lower than 40°C
1 V or less
Engine coolant temperature: Higher than 80°C
System voltage
37
MAP
Manifold absolute pressure sensor
Ignition switch: ON
0.7 - 1.2 V
Engine: Acceleration
Voltage increases
38
ETS
EGR gas temperature sensor
Ignition switch: ON
Intake air temperature: 20 °C
4.2 - 4.6 V
Intake air temperature: 50 °C
3.7 - 4.1 V
Intake air temperature: 100 °C
2.7 - 3.1 V
Intake air temperature: 200 °C
1.2 - 1.5 V
Intake air temperature: 400 °C
0.3 - 0.4 V
39
BTS
Battery temperature sensor
Ignition switch: ON
Battery temperature sensor ambient air temperature: -20°C
3.9 - 4.5 V
Battery temperature sensor ambient air temperature: 0°C
3.2 - 3.8 V
Battery temperature sensor ambient air temperature: 20°C
2.3 - 2.9 V
Battery temperature sensor ambient air temperature: 40°C
1.4 - 2.0 V
Battery temperature sensor ambient air temperature: 60°C
0.7 - 1.3 V
Battery temperature sensor ambient air temperature: 80°C
0.3 - 0.9 V
40
TPSM
Throttle position sensor

  • Remove the intake air hose at the throttle body
  • Disconnect the connector of the throttle body assembly
  • With the special tool test harness (MB991658) bridge only the mating terminals of No. 1, No. 2, and No. 4 of the disconnected connectors
  • Ignition switch: ON (engine stopped)

Fully close the throttle valve with your finger
0.3 - 0.7 V
Fully open the throttle valve with your finger
4 V or more
47
FP/R
Fuel pump relay
Ignition switch: ON
1 V or less → System voltage (after 20 seconds have passed)
55
FTS
Fuel temperature sensor
Ignition switch: ON
Fuel temperature: -20 °C
3.9 - 4.5 V
Fuel temperature: 0 °C
3.1 - 3.7 V
Fuel temperature: 20 °C
2.1 - 2.7 V
Fuel temperature: 40 °C
1.2 - 1.8 V
Fuel temperature: 60 °C
0.6 - 1.2 V
Fuel temperature: 80 °C
0.2 - 0.8 V
56
DDPS
Exhaust differential pressure sensor

  • Remove the pressure hoses, which are connected to each end of the exhaust differential pressure sensor.
  • Ignition switch: ON

Leave each end open.
0.25 - 0.75 V
Connect a manual pump (pressure-application type) to the nipple on one side, and apply pressure.
Voltage changes depending on the pressure
57
EGRP
EGR valve position sensor
Engine: Idle operation after warm-up
2 V or more
Engine: 3,500 r/min after warm-up
1.5 V or less
58
DTS1
No. 1 exhaust gas temperature sensor
Engine: Idle operation after warm-up
Exhaust gas temperature: 200 °C
3.8 - 4.2 V
Exhaust gas temperature: 400 °C
1.76 - 2.16 V
Exhaust gas temperature: 600 °C
0.66 - 1.06 V
Exhaust gas temperature: 800 °C
0.22 - 0.62 V
59
DTS2
No. 2 exhaust gas temperature sensor (catalyst temperature)
Engine: Idle operation after warm-up
Catalyst temperature: 200 °C
3.8 - 4.2 V
Catalyst temperature: 400 °C
1.76 - 2.16 V
Catalyst temperature: 600 °C
0.66 - 1.06 V
Catalyst temperature: 800 °C
0.22 - 0.62 V
60
DTS3
No. 3 exhaust gas temperature sensor (DPF temperature)
Engine: Idle operation after warm-up
DPF temperature: 200 °C
3.8 - 4.2 V
DPF temperature: 400 °C
1.76 - 2.16 V
DPF temperature: 600 °C
0.66 - 1.06 V
DPF temperature: 800 °C
0.22 - 0.62 V
62
ATS
Intake air temperature sensor
Ignition switch: ON
Intake air temperature: -20 °C
4.0 - 4.6 V
Intake air temperature: 0 °C
3.1 - 3.7 V
Intake air temperature: 20 °C
2.1 - 2.7 V
Intake air temperature: 40 °C
1.2 - 1.8 V
Intake air temperature: 60 °C
0.6 - 1.2 V
Intake air temperature: 80 °C
0.2 - 0.8 V
63
WTS
Engine coolant temperature sensor
Ignition switch: ON
Engine coolant temperature: -20 °C
4.4 - 4.9 V
Engine coolant temperature: 0 °C
4.4 - 4.6 V
Engine coolant temperature: 20 °C
3.3 - 3.9 V
Engine coolant temperature: 40 °C
2.4 - 3.0 V
Engine coolant temperature: 60 °C
1.5 - 2.1 V
Engine coolant temperature: 80 °C
0.9 - 1.5 V
64
FPS
Rail pressure sensor
Engine: Idle operation after warm-up
1.15 - 1.75 V
66
SGC
Camshaft position sensor
Engine: Cranking
0.1 - 3.0 V*1
Engine: Idle operation
0.5 - 1.5 V*1
67
SGT
Crank angle sensor
Engine: Cranking
1.5 - 4.5 V*1
Engine: Idle operation
2.5 - 3.5 V*1
68
SGTB
Power supply voltage applied to crank angle sensor
Ignition switch: ON
4.9 - 5.1 V
69
SGCB
Power supply voltage applied to camshaft position sensor
Ignition switch: ON
4.9 - 5.1 V
70
FPS5
Power supply voltage applied to rail pressure sensor
Ignition switch: ON
4.9 - 5.1 V
71
EGR5
Power supply voltage applied to EGR valve position sensor
Ignition switch: ON
4.9 - 5.1 V
72
MAP5
Power supply voltage applied to manifold absolute pressure sensor
Ignition switch: ON
4.9 - 5.1 V
93
TPS5
Power supply voltage applied to throttle position sensor
Ignition switch: ON
4.9 - 5.1 V
94
DDP5
Power supply voltage applied to exhaust differential pressure sensor
Ignition switch: ON
4.9 - 5.1 V
101
BAT1
Power supply
Ignition switch: ON
System voltage
102
BAT2
103
BACK
Backup power supply
Ignition switch: "LOCK" (OFF)
System voltage
104
IGN
Ignition switch-IG
Ignition switch: ON
System voltage
111
ST
Ignition switch-ST
Engine: Cranking
System voltage
114
ETV+
Throttle valve control servo (+)
Engine: Stopped from idling speed
Voltage changes for few seconds
115
EGR+
EGR valve (+)
Engine: Idle operation after warm-up
1 - 3 V*1
Engine: 3,500 r/min after warm-up
1 V or less
118
C/R
Engine control relay
Ignition switch: "LOCK" (OFF)
System voltage
Ignition switch: ON
1 V or less
120
G/CT
Glow control unit
Engine: Idling
Engine coolant temperature: lower than 40°C
System voltage
Engine coolant temperature: lower than 80°C
1 V or less
121
ALTG
Alternator G terminal

  • Engine: Idle operation after warm-up
  • Radiator fan: Non-operation
  • Headlamp switch: OFF → ON
  • Stop lamp: OFF → ON
  • Rear defogger switch: OFF → ON

Voltage increases
125
G/DA
Glow diagnostic signal
Engine: Idling
Engine coolant temperature: lower than 40°C
System voltage
Engine coolant temperature: lower than 80°C
1 V or less
129
ETV-
Throttle valve control servo (-)
Engine: Stopped from idling speed
Voltage changes for few seconds
131
SCV+
Suction control valve (+)
Engine: Idle operation
5 - 6 V*1
Engine: Acceleration
Voltage decreases
134
AP5
Power supply voltage applied to accelerator pedal position sensor (sub)
Ignition switch: ON
4.9 - 5.1 V
135
APSS
Accelerator pedal position sensor (sub)
Ignition switch: ON
Release the accelerator pedal
0.2 - 0.8 V
Depress the accelerator pedal fully
2 V or more
138
ECB
Battery current sensor
The battery is being discharged.

  • Engine: Cranking
The value changes by the value less than 3.5 V.
The battery is being charged.

  • Leave the ignition switch being in the ON position for several minutes, and then after the engine start.
The value gradually increases from the value more than 3.5 V*2
140
AFS
Air flow sensor
Engine: Gradually increase the speed
Voltage increases
141
ALTF
Alternator FR terminal

  • Engine: Idle operation after warm-up
  • Radiator fan: Non-operation
  • Headlamp switch: OFF → ON
  • Stop lamp: OFF → ON
  • Rear defogger switch: OFF → ON

Voltage decreases
148
ECB5
Power supply voltage applied to battery current sensor
Ignition switch: ON
4.9 - 5.1 V
149
APS5
Power supply voltage applied to accelerator pedal position sensor (main)
Ignition switch: ON
4.9 - 5.1 V
150
APSM
Accelerator pedal position sensor (main)
Ignition switch: ON
Release the accelerator pedal
0.7 - 1.3 V
Depress the accelerator pedal fully
4 V or more
note *1: The average voltage is shown when an analogue voltmeter is used (because the average voltage might not be shown stably when digital voltmeter is used).
note *2: If the battery is fully charged, the output reading may be incorrect.

CHECK CHART FOR RESISTANCE AND CONTINUITY BETWEEN TERMINALS


1.Turn the ignition switch to "LOCK" (OFF) position.
2.Disconnect the engine-ECU connector.
3.Measure the resistance and check for continuity between the terminals of the engine-ECU harness-side connector while referring to the check chart.
note
  1. When measuring resistance and checking continuity, a harness for checking contact pin pressure should be used instead of inserting a test probe.
  2. The chart procedures do not have the particular order.
caution If the terminals that should be checked are mistaken, or if connector terminals are not correctly shorted to earth, damage may be caused to the vehicle wiring, sensors, engine-ECU and/or ohmmeter. Be careful to prevent this!
4.If the ohmmeter shows any deviation from the standard value, check the corresponding sensor, actuator and related electrical wiring, and the repair or replace.
5.After repair or replacement, recheck with the ohmmeter to confirm that the repair or replacement has corrected the problem.


Terminal No.
Terminal code
Inspection item
Normal condition (Check condition)
1 - 2
I/B1 - INJ1
No. 1 injector
Approximately 0.45 Ω (at 20°C)
73 - 75
I/B2 - INJ2
No. 2 injector
49 - 50
I/B3 - INJ3
No. 3 injector
25 - 27
I/B4 - INJ4
No. 4 injector
17 - 101
VGT - BAT1
Variable geometry control solenoid valve
10 - 14 Ω (at 20°C)
23 - 101
EGC - BAT1
EGR cooler bypass control solenoid valve
29 - 35 Ω (at 20°C)
32 - 38
ETSE - ETS
EGR gas temperature sensor
55 - 78 kΩ (at -20°C)
29 - 41 kΩ (at 0°C)
17 - 23 kΩ (at 20°C)
10 - 14 kΩ (at 40°C)
7.1 - 8.8 kΩ (at 60°C)
4.8 - 5.9 kΩ (at 80°C)
39 - 155
BTS - AFSE&ECBE
Battery temperature sensor
4.9 - 5.3 kΩ (When battery temperature sensor ambient air temperature is 0 °C)
2.2 - 2.6 kΩ (When battery temperature sensor ambient air temperature is 20 °C)
1.0 - 1.4 kΩ (When battery temperature sensor ambient air temperature is 40 °C)
55 - 79
FTS - FTSE
Fuel temperature sensor
Approximately 2.0 - 3.0 kΩ (at 20 °C)
58 - 82
DTS1 - DT1E
No. 1 exhaust gas temperature sensor
75 - 190 kΩ (at 20°C)
59 - 83
DTS2 - DT2E
No. 2 exhaust gas temperature sensor (catalyst temperature)
75 - 190 kΩ (at 20°C)
60 - 84
DTS3 - DT3E
No. 3 exhaust gas temperature sensor (DPF temperature)
75 - 190 kΩ (at 20°C)
62 - 86
ATS - ATSE
Intake air temperature sensor
13 - 18 kΩ (at -20°C)
4.8 - 7.0 kΩ (at 0°C)
2.1 - 2.8 kΩ (at 20°C)
0.9 - 1.5 kΩ (at 40°C)
0.47 - 0.69 kΩ (at 60°C)
0.27 - 0.39 kΩ (at 80°C)
63 - 87
WTS - WTSE
Engine coolant temperature sensor
14 - 17 kΩ (at -20°C)
5.1 - 6.5 kΩ (at 0°C)
2.1 - 2.7 kΩ (at 20°C)
0.9 - 1.3 kΩ (at 40°C)
0.48 - 0.68 kΩ (at 60°C)
0.26 - 0.36 kΩ (at 80°C)
116 - Body earth
GNDB - Body earth
Engine-ECU earth
Continuity (2 Ω or less)
117 - Body earth
GNDE - Body earth
145 - Body earth
SGND - Body earth
114 - 129
ETV+ - ETV-
Throttle valve control servo
0.3 - 100 Ω (at 20 °C)
131 - 146
SCV+ - SCV-
Suction control valve
Approximately 2.1 Ω (at 20°C)