Pinout Values and Diagnostic Parameters
BRAKE CONTROL: ELECTRONICALLY CONTROLLED BRAKE SYSTEM:
TERMINALS OF ECU
1. CHECK BATTERY VOLTAGE
(a) Measure the battery voltage.
Voltage:
10 to 14 V
2. SKID CONTROL ECU ASSEMBLY INSPECTION
(a) Measure the voltage between each terminal or between each terminal and the body ground.
(b) Connect Techstream to the DLC3, and check the communication condition with the skid control ECU.
(c) Using an oscilloscope, check that the pulse generates between each terminal or between each terminal and the body ground.
NOTICE:
- Inspection should be performed from the back of the connector with the connector connected to the skid control ECU.
- The voltage between the terminals of the brake actuator assembly may become 0 V due to the fail safe function when the brake control warning light comes on (malfunctioning).
HINT: Inspect the ECU from the wire harness side while the connector is connected.
SKID CONTROL ECU
(d) Waveform 1
NOTE: Normal waveform is output only when BS 1 and 2 voltages are normal (10 to 14 V).
- While driving at approximately 12 mph (20 km/h).
- 5 V/DIV, 200 ms/DIV.
- Brake pedal depressed.
(e) Waveform 2
NOTE: Normal waveform is output only when BS 1 and 2 voltages are normal (10 to 14 V).
- While driving at approximately 12 mph (20 km/h).
- 5 V/DIV, 200 ms/DIV.
- Brake pedal depressed -> released
(f) Waveform 3
NOTE: As the vehicle speed (tire rotating speed) becomes faster, the cycle becomes shorter and the output voltage larger.
- 1 V/DIV, 2 ms/DIV.
- While driving at approximately 18 mph (30 km/h).
(g) Waveform 4
NOTE: As the vehicle speed (tire rotating speed) becomes faster, the cycle becomes shorter.
- 5 V/DIV, 50 ms/DIV.
- While driving at approximately 12 mph (20 km/h).
(h) Waveform 5
- 5 V/DIV, 200 ms/DIV.
- IG switch ON
(i) Waveform 6
- 5 V/DIV, 100 ms/DIV.
- IG switch ON
(j) Waveform 7
NOTE: As the vehicle speed (tire rotating speed) becomes faster, the cycle becomes shorter.
- 1 V/DIV, 2 ms/DIV.
- While driving at approximately 12 mph (20 km/h).