TERMINALS OF ECU
TERMINALS OF ECU
| *a | Component without harness connected (Skid Control ECU (Brake Actuator Assembly)) | - | - |
| Terminal No. (Symbol) | Terminal Description |
|---|---|
| 1 (GND1) | Skid control ECU (brake actuator assembly) ground |
| 2 | - |
| 3 | - |
| 4 (RL-) | Rear wheel speed LH (-) signal input |
| 5 (RL+) | Rear wheel speed LH (+) power supply output |
| 6 (FR-) | Front wheel speed RH (-) signal input |
| 7 (FR+) | Front wheel speed RH (+) power supply output |
| 8 | - |
| 9 (CSW) | VSC OFF switch (combination switch assembly) input |
| 10 | - |
| 11 (STP) | Stop light switch assembly input |
| 12 | - |
| 13 | - |
| 14 (+BS) | Solenoid relay power supply |
| 15 | - |
| 16 | - |
| 17 | - |
| 18 (SP1) | Speed signal output for speedometer |
| 19 (RR-) | Rear wheel speed RH (-) signal input |
| 20 (RR+) | Rear wheel speed RH (+) power supply output |
| 21 (FL-) | Front wheel speed LH (-) signal input |
| 22 (FL+) | Front wheel speed LH (+) power supply output |
| 23 | - |
| 24 | - |
| 25 | - |
| 26 | - |
| 27 (CANH) | CAN communication line H |
| 28 (FSW+) | Brake pedal load sensing switch (brake pedal support assembly) input |
| 29 | - |
| 30 (GND2) | Pump motor ground |
| 31 | - |
| 32 (STPO) | Stop light control relay output |
| 33 | - |
| 34 | - |
| 35 (PKB) | Brake hold switch (electric parking brake switch assembly) input |
| 36 | - |
| 37 (STP2) | Stop light signal input |
| 38 | - |
| 39 | - |
| 40 | - |
| 41 | - |
| 42 | - |
| 43 (CANL) | CAN communication line L |
| 44 | - |
| 45 (IG1) | ECU power supply input |
| 46 (BM) | Motor relay power supply |
TERMINAL INSPECTION
(a) Disconnect the A41 connector and measure the voltage or resistance on the wire harness side.
| *a | Front view of wire harness connector (to Skid Control ECU (Brake Actuator Assembly)) | - | - |
HINT:
Voltage cannot be measured with the connector connected to the skid control (brake actuator assembly) as the connector is watertight.
| Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
| A41-1 (GND1) - Body ground | W-B - Body ground | Skid control ECU (brake actuator assembly) ground | 1 minute or more after disconnecting the cable from the negative (-) battery terminal | Below 1 Ω |
| A41-9 (CSW) - Body ground | P - Body ground | VSC OFF switch (combination switch assembly) input | VSC OFF switch (combination switch assembly) pressed and held → released | Below 1 Ω → 10 kΩ or higher |
| A41-11 (STP) - Body ground | B - Body ground | Stop light switch assembly input | Stop light switch assembly on → off (brake pedal depressed → released) | 8 to 14 V → Below 1.5 V |
| A41-14 (+BS) - Body ground | L - Body ground | Solenoid relay power supply | Always | 11 to 14 V |
| A41-18 (SP1) - Body ground | BE - Body ground | Speed signal output for speedometer | Engine switch on (IG) | 11 to 14 V |
| A41-28 (FSW+) - Body ground | W - Body ground | Brake pedal load sensing switch (brake pedal support assembly) input | Brake pedal depressed → released | 950 to 1050 Ω → 203 to 223 Ω |
| A41-30 (GND2) - Body ground | W-B - Body ground | Pump motor ground | 1 minute or more after disconnecting the cable from the negative (-) battery terminal | Below 1 Ω |
| A41-32 (STPO) - Body ground | B - Body ground | Semiconductor PWR integration ECU output | Engine switch on (IG) | 11 to 14 V |
| A41-35 (PKB) - Body ground | R - Body ground | Brake hold switch (electric parking brake switch assembly) input | Brake hold switch (electric parking brake switch assembly) pressed and held → released | Below 1 Ω → 10 kΩ or higher |
| A41-37 (STP2) - Body ground | P - Body ground | Stop light signal input | Brake pedal depressed → released | 8 to 14 V → Below 1.5 V |
| A41-45 (IG1) - Body ground | V - Body ground | ECU power supply input | Engine switch on (IG) | 11 to 14 V |
| A41-46 (BM) - Body ground | R - Body ground | Motor relay power supply | Always | 11 to 14 V |
Problem Symptoms Table
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