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METER / GAUGE SYSTEM > TERMINALS OF ECU

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COMBINATION METER ASSEMBLY

E188249E01

  1. Measure the voltage and resistance according to the value(s) in the table below.

    Terminal No. (Symbol)
    		Wiring Color
    		Terminal Description
    		Condition
    		Specified Condition
    L27-2 (TC O)*1 - Body ground
    		G - Body ground
    		Trip switch signal (Unit change switch)
    		Unit change switch not pressed
    		11 to 14 V
    Unit change switch pressed
    		Below 1 V
    L27-2 (TC O)*2 - Body ground
    		G - Body ground
    		Trip switch signal (Tail cancel switch)
    		Tail cancel switch not pressed
    		11 to 14 V
    Tail cancel switch pressed
    		Below 1 V
    L27-5 (S) - Body ground
    		R - Body ground
    		Oil pressure switch signal
    		Power switch on (IG), oil pressure warning display off
    		Below 1 V
    Power switch on (IG), oil pressure warning display comes on
    		11 to 14 V
    L27-6 (LVWG) - Body ground
    		L - Body ground
    		Headlight leveling indicator light signal
    		Power switch on (IG), headlight leveling indicator light off
    		11 to 14 V
    Power switch on (IG), headlight leveling indicator light blinks
    		Below 1 V ←→ 11 to 14 V
    L27-7 (+S) - Body ground
    		V - Body ground
    		Speed signal for other systems (Output)
    		Power switch on (IG), front wheel turns slowly
    		Pulse generation
    (See waveform 1)
    L27-8 (SI) - Body ground
    		V - Body ground
    		Speed signal (Input)
    		Power switch on (IG), front wheel turns slowly
    		Pulse generation
    (See waveform 1)
    L27-9 (E2) - Body ground
    		G - Body ground
    		Ground (Coolant temperature sensor ground)
    		Always
    		Below 1 Ω
    L27-10 (CANH) - Body ground
    		P - Body ground
    		CAN communication signal
    		Power switch off
    		200 Ω or higher
    L27-11 (CANL) - Body ground
    		W - Body ground
    		CAN communication signal
    		Power switch off
    		200 Ω or higher
    L27-12 (HOUR) - Body ground
    		B - Body ground
    		Trip switch signal (Hour adjust switch)
    		Hour adjust switch not pressed
    		11 to 14 V
    Hour adjust switch pressed
    		Below 1 V
    L27-13 (MIN) - Body ground
    		B - Body ground
    		Trip switch signal (Minute adjust switch)
    		Minute adjust switch not pressed
    		11 to 14 V
    Minute adjust switch pressed
    		Below 1 V
    L27-14 (L) - Body ground
    		B - Body ground
    		Fuel level signal
    		Power switch on (IG), fuel level warning light OFF
    		Below 1 V
    Power switch on (IG), fuel level warning light ON
    		3 to 7 V
    L27-15 (ES2) - Body ground
    		W - Body ground
    		Ground (Fuel ground)
    		Always
    		Below 1 Ω
    L27-16 (TWS3) - Body ground
    		B - Body ground
    		Coolant temperature sensor signal
    		Power switch on (IG), coolant temperature below 113°C (235°F)
    		0.2 to 4.8 V
    Power switch on (IG), coolant temperature below 120°C (248°F) or more
    		Below 0.15 V
    L27-17 (RST) - Body ground
    		R - Body ground
    		Trip switch signal (Set switch)
    		Set switch not pressed
    		11 to 14 V
    Set switch pressed
    		Below 1 V
    L27-18 (B) - Body ground
    		R - Body ground
    		Battery
    		Power switch off
    		11 to 14 V
    L27-19 (IG+) - Body ground
    		L - Body ground
    		Power switch signal
    		Power switch off
    		Below 1 V
    Power switch on (IG)
    		11 to 14 V
    L27-20 (IG2) - Body ground
    		G - Body ground
    		Power switch signal
    		Power switch off
    		Below 1 V
    Power switch on (IG)
    		11 to 14 V
    L27-21 (PBLT) - Body ground
    		Y - Body ground
    		Front passenger side seat belt warning light signal
    		Power switch on (IG), front passenger side seat belt warning light off
    		11 to 14 V
    Power switch on (IG), front passenger side seat belt warning light blinks
    		Below 1 V ←→ 11 to 14 V
    L27-22 (LP) - Body ground
    		B - Body ground
    		Security indicator light signal
    		Power switch on (IG), security indicator light off
    		Below 2 V
    Security indicator light blinks
    		Pulse generation
    L27-24 (SW) - Body ground
    		P - Body ground
    		Front passenger side seat belt buckle switch signal
    		Power switch on (IG), sit on the front passenger seat, and front passenger side seat belt unfastened
    		Below 1 V
    Power switch on (IG), sit on the front passenger seat, and front passenger side seat belt fastened
    		11 to 14 V
    L27-25 (EFI) - Body ground
    		LG - Body ground
    		MIL (Check engine warning light) signal
    		Power switch on (IG), MIL (Check engine warning light) off
    		11 to 14 V
    Power switch on (IG), MIL (Check engine warning light) comes on
    		Below 1 V
    L27-26 (B) - Body ground
    		Y - Body ground
    		Turn LH indicator light signal
    		Power switch on (IG), turn LH indicator light off
    		11 to 14 V
    Power switch on (IG), turn LH indicator light blinks
    		Below 1 V ←→ 11 to 14 V
    L27-27 (B) - Body ground
    		G - Body ground
    		Turn RH indicator light signal
    		Power switch on (IG), turn RH indicator light off
    		11 to 14 V
    Power switch on (IG), turn RH indicator light blinks
    		Below 1 V ←→ 11 to 14 V
    L27-29 (STRG) - Body ground
    		G - Body ground
    		Steering pad switch signal
    		Always
    		Pulse generation
    L27-30 (ES) - Body ground
    		BR - Body ground
    		Ground (Signal ground)
    		Always
    		Below 1 Ω
    L27-32 (RRSB)*3 - Body ground
    		R - Body ground
    		Rear RH passenger seat belt buckle switch signal
    		Power switch on (IG), rear RH passenger seat belt unfastened
    		Below 1 V
    Power switch on (IG), rear RH passenger seat belt fastened
    		11 to 14 V
    L27-33 (RCSB)*3 - Body ground
    		L - Body ground
    		Rear center passenger seat belt buckle switch signal
    		Power switch on (IG), rear center passenger seat belt unfastened
    		Below 1 V
    Power switch on (IG), rear center passenger seat belt fastened
    		11 to 14 V
    L27-34 (RLSB)*3 - Body ground
    		Y - Body ground
    		Rear left passenger seat belt buckle switch signal
    		Power switch on (IG), rear left passenger seat belt unfastened
    		Below 1 V
    Power switch on (IG), rear left passenger seat belt fastened
    		11 to 14 V
    L106-1 (12V) - Body ground
    		B - Body ground
    		Power switch signal
    		Power switch off
    		11 to 14 V
    L106-4 (GND) - Body ground
    		W - Body ground
    		Ground
    		Always
    		Below 1 Ω
    L106-5 (BKR) - Body ground
    		P - Body ground
    		Headup display illumination signal
    		Power switch on (IG)
    		Pulse generation
    L106-6 (LAT) - Body ground
    		R - Body ground
    		Headup display dot illumination timing signal
    		Power switch on (IG)
    		Pulse generation
    L106-7 (CLKH) - Body ground
    		R - Body ground
    		Clock signal
    		Always
    		Pulse generation
    L106-8 (CLKL) - Body ground
    		G - Body ground
    		Clock signal
    		Always
    		Pulse generation
    L106-9 (SIH) - Body ground
    		G - Body ground
    		Headup display dot signal
    		Power switch on (IG)
    		Pulse generation
    L106-10 (SIL) - Body ground
    		R - Body ground
    		Headup display dot signal
    		Power switch on (IG)
    		Pulse generation
    L106-11 (WE) - Body ground
    		L - Body ground
    		Headup display dot illumination signal
    		Power switch on (IG), headup display illuminated
    		Pulse generation
    L106-14 (STP1) - Body ground
    		V - Body ground
    		Stepper motor signal
    		Power switch on (IG)
    		Pulse generation
    L106-15 (STP2) - Body ground
    		LG - Body ground
    		Stepper motor signal
    		Power switch on (IG)
    		Pulse generation
    L106-16 (STP3) - Body ground
    		B - Body ground
    		Stepper motor signal
    		Power switch on (IG)
    		Pulse generation
    L106-17 (STP4) - Body ground
    		W - Body ground
    		Stepper motor signal
    		Power switch on (IG)
    		Pulse generation
    L107-1 (NVSW) - L107-2 (E)
    		V - BE
    		Navigation system display select switch signal
    		Turn the power switch on (IG), navigation system display select switch not pressed
    		Below 1 V
    Turn the power switch on (IG), navigation system display select switch pressed
    		11 to 14 V
    L107-2 (E) - Body ground
    		BE - Body ground
    		Ground
    		Always
    		Below 1 Ω
    L107-3 (HUDI) - Body ground
    		W - Body ground
    		Headup display indicator light signal
    		Turn the power switch on (IG), headup display indicator light goes off
    		Below 1 V
    Turn the power switch on (IG), headup display indicator light comes on
    		11 to 14 V
    L107-4 (HUDD) - L107-2 (E)
    		R - BE
    		Headup display position down switch signal
    		Turn the power switch on (IG), headup display position down switch not pressed
    		Below 1 V
    Turn the power switch on (IG), headup display position down switch pressed
    		11 to 14 V
    L107-7 (HDS) - L107-2 (E)
    		P - BE
    		Headup display position up switch signal
    		Turn the power switch on (IG), headup display position down switch not pressed
    		Below 1 V
    Turn the power switch on (IG), headup display position down switch pressed
    		11 to 14 V
    L107-8 (HUDO) - L107-2 (E)
    		B - BE
    		Headup display mode select switch signal
    		Turn the power switch on (IG), headup display mode select switch not pressed
    		Below 1 V
    Turn the power switch on (IG), headup display mode select switch pressed
    		11 to 14 V
    L107-9 (IIND) - Body ground
    		BE - Body ground
    		Navigation system indicator light signal
    		Turn the power switch on (IG), navigation system indicator light goes off
    		Below 1 V
    Turn the power switch on (IG), navigation system indicator light comes on
    		11 to 14 V

    1. *1: w/ Unit Change Switch
    2. *2: w/o Unit Change Switch
    3. *3: w/ Rear Seat Belt Reminder



    2. I043789E03

  2. Waveform 1 (Reference): Using an oscilloscope:
    Item
    		Condition
    Tool setting
    		5 V/DIV., 20 ms./DIV.
    Vehicle condition
    		Driving at approx. 20 km/h (12 mph)

    HINT:
    When the system is functioning normally, one wheel revolution generates 4 pulses. As the vehicle speed increases, the width indicated by (A) in the illustration narrows.


COMBINATION METER ASSEMBLY INNER CIRCUIT

E188171E02


E188172E02


E188173E02


Terminal No. (Symbol)
Wire Harness Side
L27
1
-
2 (TC O)
Trip Switch
3
-
4
-
5 (S)
Oil Pressure Switch
6 (LVWG)
Headlight Leveling ECU Assembly
7 (+S)
Each part that uses the speed signal
8 (SI)
Skid Control ECU
9 (E2)
Ground (Coolant Temperature Sensor Ground)
10 (CANH)
CAN Communication Line
11 (CANL)
CAN Communication Line
12 (HOUR)
Trip Switch
13 (MIN)
Trip Switch
14 (L)
Fuel Sender Gauge Assembly
15 (ES2)
Fuel Sender Gauge Assembly
16 (TWS3)
Coolant Temperature Sensor
17 (RST)
Trip Switch
18 (B)
ECU-B Fuse
19 (IG+)
MET Fuse
20 (IG2)
IGN Fuse
21 (PBLT)
Telltale Light Assembly
22 (LP)
Certification ECU (Smart Key ECU Assembly)
23
-
24 (SW)
Front Seat Inner Belt Assembly RH*2 or Front Seat Inner Belt Assembly LH*3
25 (EFI)
Power Management Control ECU
26 (B)
Turn Signal Flasher
27 (B)
Turn Signal Flasher
28
-
29 (STRG)
Steering Pad Switch Assembly
30 (ES)
Ground
31
-
32 (RRSB)
Rear Seat Inner Belt Assembly RH*1
33 (RCSB)
Rear Seat Inner Belt Assembly Center*1
34 (RLSB)
Rear Seat Inner Belt Assembly LH*1
35
-
36
-
37
-
38
-
39
-
40
-
  1. *1: w/ Rear Seat Belt Warning
  2. *2: for LHD
  3. *3: for RHD

Terminal No. (Symbol)
Wire Harness Side
L106
1 (12V)
Headup Display
2
-
3
-
4 (GND)
Ground
5 (BKR)
Headup Display (Combination Meter Mirror ECU)
6 (LAT)
Headup Display (Combination Meter Mirror ECU)
7 (CLKH)
Headup Display (Combination Meter Mirror ECU)
8 (CLKL)
Headup Display (Combination Meter Mirror ECU)
9 (SIH)
Headup Display (Combination Meter Mirror ECU)
10 (SIL)
Headup Display (Combination Meter Mirror ECU)
11 (WE)
Headup Display (Combination Meter Mirror ECU)
12
-
13
-
14 (STP1)
Headup Display (Combination Meter Mirror ECU)
15 (STP2)
Headup Display (Combination Meter Mirror ECU)
16 (STP3)
Headup Display (Combination Meter Mirror ECU)
17 (STP4)
Headup Display (Combination Meter Mirror ECU)
18
-
19
-
20
-
21
-
22
-
23
-
24
-
L107
1 (NVSW)
Trip Switch
2 (E)
Trip Switch
3 (HUDI)
Trip Switch
4 (HUDD)
Trip Switch
5
-
6
-
7 (HDS)
Trip Switch
8 (HUDO)
Trip Switch
9 (IIND)
Trip Switch
10
-
11
-
12
-
13
-
14
-
15
-
16
-