Lexus NX: Terminals Of Ecu
TERMINALS OF ECU
TERMINALS OF ECU
| *a | Component without harness connected (Skid Control ECU (Brake Booster with Master Cylinder Assembly)) | - | - |
| Terminal No. (Symbol) | Terminal Description |
|---|---|
| 1 (MRI1) | Motor power supply input 1 |
| 2 (MRI2) | Motor power supply input 2 |
| 3 (STPO) | Stop light control ECU assembly output |
| 4 | - (Not used) |
| 5 (FR-) | Front speed sensor RH (-) signal input |
| 6 (STP2) | Stop light control ECU assembly input |
| 7 (RL-) | Rear speed sensor LH (-) signal input |
| 8 (CSW) | VSC OFF switch (Integration control and panel assembly) input |
| 9 (RR-) | Rear speed sensor RH (-) signal input |
| 10 (HZRI) | Brake hold switch (Integration control and panel assembly) input |
| 11 (SP1) | Speed sensor signal output |
| 12 (IG2) | IG2 power source input |
| 13 | - (Not used) |
| 14 (BI) | +B power source input |
| 15 (BS) | Solenoid power supply input |
| 16 (IG1) | IG1 power source input |
| 17 | - (Not used) |
| 18 (FR+) | Front speed sensor RH (+) power supply output |
| 19 (CTY) | Front door courtesy light switch assembly input |
| 20 (RL+) | Rear speed sensor LH (+) power supply output |
| 21 | - (Not used) |
| 22 (RR+) | Rear speed sensor RH (+) power supply output |
| 23 (GND6) | Skid control ECU (Brake booster with master cylinder assembly) ground 6 |
| 24 (GND5) | Skid control ECU (Brake booster with master cylinder assembly) ground 5 |
| 25 (GND4) | Skid control ECU (Brake booster with master cylinder assembly) ground 4 |
| 26 (GND3) | Skid control ECU (Brake booster with master cylinder assembly) ground 3 |
| 27 (GND2) | Skid control ECU (Brake booster with master cylinder assembly) ground 2 |
| 28 (GND) | Skid control ECU (Brake booster with master cylinder assembly) ground |
| 29 (MRO1) | Motor power supply output 1 |
| 30 (MRO2) | Motor power supply output 2 |
| 31 (FL+) | Front speed sensor LH (+) power supply output |
| 32 (FL-) | Front speed sensor LH (-) signal input |
| 33 (STP) | Stop light switch assembly input |
| 34 (CA2L) | CAN communication line 2 (L) |
| 35 (CA2H) | CAN communication line 2 (H) |
| 36 (LBL) | Brake fluid level warning switch input |
| 37 (CA1H) | CAN communication line 1 (H) |
| 38 (CA1L) | CAN communication line 1 (L) |
| 39 (VCSK) | Brake pedal stroke sensor assembly power supply output |
| 40 (SKS2) | Brake pedal stroke sensor assembly signal input 2 |
| 41 (SKG) | Brake pedal stroke sensor assembly ground |
| 42 (SKS) | Brake pedal stroke sensor assembly signal input |
TERMINAL INSPECTION
(a) Disconnect the connector and measure the voltage or resistance on the wire harness side.
| *a | Front view of wire harness connector (to Skid Control ECU (Brake Booster with Master Cylinder Assembly)) | - | - |
HINT:
The voltage cannot be measured with the connector connected to the skid control ECU (brake booster with master cylinder assembly) as the connector is watertight.
Standard| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| A57-1 (MRI1) - Body ground | B - Body ground | Motor power supply input 1 | Always | 11 to 14 V |
| A57-2 (MRI2) - Body ground | R - Body ground | Motor power supply input 2 | Always | 11 to 14 V |
| A57-3 (STPO) - Body ground | R - Body ground | Stop light control ECU assembly output | Power switch on (IG) | 11 to 14 V |
| A57-6 (STP2) - Body ground | L - Body ground | Stop light control ECU assembly input | Brake pedal depressed → released | 11 to 14 V → Below 1.5 V |
| A57-8 (CSW) - Body ground | L - Body ground | VSC OFF switch (Integration control and panel assembly) input | VSC OFF switch (integration control and panel assembly) pressed and held → released | Below 1 Ω → 10 kΩ or higher |
| A57-10 (HZRI) - Body ground | R - Body ground | Brake hold switch (Integration control and panel assembly) input | Brake hold switch (integration control and panel assembly) pressed and held → released | Below 1 Ω → 10 kΩ or higher |
| A57-12 (IG2) - Body ground | B - Body ground | IG2 power source input | Power switch on (IG) | 11 to 14 V |
| A57-14 (BI) - Body ground | B - Body ground | +B power source input | Always | 11 to 14 V |
| A57-15 (BS) - Body ground | B - Body ground | Solenoid power supply input | Always | 11 to 14 V |
| A57-16 (IG1) - Body ground | L - Body ground | IG1 power source input | Power switch on (IG) | 11 to 14 V |
| A57-19 (CTY) - Body ground | W - Body ground | Front door courtesy light switch assembly input | Driver door closed → open | Pulse generation → Below 1.5 V |
| A57-23 (GND6) - Body ground | W-B - Body ground | Skid control ECU (Brake booster with master cylinder assembly) ground 6 | Always | Below 1 Ω |
| A57-24 (GND5) - Body ground | W-B - Body ground | Skid control ECU (Brake booster with master cylinder assembly) ground 5 | Always | Below 1 Ω |
| A57-25 (GND4) - Body ground | W-B - Body ground | Skid control ECU (Brake booster with master cylinder assembly) ground 4 | Always | Below 1 Ω |
| A57-26 (GND3) - Body ground | W-B - Body ground | Skid control ECU (Brake booster with master cylinder assembly) ground 3 | Always | Below 1 Ω |
| A57-27 (GND2) - Body ground | W-B - Body ground | Skid control ECU (Brake booster with master cylinder assembly) ground 2 | Always | Below 1 Ω |
| A57-28 (GND) - Body ground | W-B - Body ground | Skid control ECU (Brake booster with master cylinder assembly) ground | Always | Below 1 Ω |
| A57-33 (STP) - Body ground | LG - Body ground | Stop light switch assembly input | Stop light switch assembly on → off (Brake pedal depressed → released) | 11 to 14 V → Below 1.5 V |
| A57-36 (LBL) - Body ground | V - Body ground | Brake fluid level warning switch input | Brake fluid level warning switch off → on | 1.84 to 2.16 kΩ → Below 1 Ω |
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