- Skid control ECU (brake actuator assembly)
- Wire harness or connector
| Last Modified: 04-05-2023 | 6.11:8.1.0 | Doc ID: RM1000000018KEU |
| Model Year Start: 2018 | Model: Sienna | Prod Date Range: [11/2017 - ] |
| Title: BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: C142B-C146D; Motor Power Supply Voltage Circuit; 2018 - 2020 MY Sienna [11/2017 - ] | ||
|
DTC |
C142B |
Motor Power Supply Voltage Circuit |
|
DTC |
C146C |
Open in ABS Motor Relay Circuit |
|
DTC |
C146D |
Short in ABS Motor Relay Circuit |
DESCRIPTION
The motor relay and motor fail-safe relay are built into the brake actuator assembly.
During ABS, TRAC, VSC or brake assist operation, the skid control ECU (brake actuator assembly) turns on the motor relay to run the pump motor in the brake actuator assembly.
When a motor system DTC is stored, the motor fail-safe relay cuts the power source supply to the motor relay for fail-safe operation.
These DTCs may be stored when the voltage to the motor relay power source (BM terminal) is lower than the DTC detection condition due to low output from the battery or alternator.
|
DTC No. |
DTC Detection Condition |
Trouble Area |
|---|---|---|
|
C142B |
When voltage at +BS terminal is 9.5 V or higher, open in BM terminal continues for 1 second or more. |
|
|
C146C |
When voltage at +BS terminal is 9.5 V or higher and motor relay ON while control operates, relay contact OFF condition continues for 0.12 seconds or more. |
|
|
C146D |
Any of the following is detected:
|
|
WIRING DIAGRAM
Refer to DTCs C1427 (See page
![2018 - 2020 MY Sienna [11/2017 - ]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: VEHICLE STABILITY CONTROL SYSTEM: C1427; Motor Malfunction](/t3Portal/stylegraphics/info.gif)
).
CAUTION / NOTICE / HINT
NOTICE:
-
When replacing the skid control ECU (brake actuator assembly), perform zero point calibration and store system information (See page
).
- Inspect the fuses for circuits related to this system before performing the following inspection procedure.
HINT:
When C1241 and/or C1417 is output together with C142B, C146C and/or C146D, inspect and repair the trouble areas indicated by C1241 and/or C1417 first (See page
, and/or
).
PROCEDURE
|
1. |
CHECK TERMINAL VOLTAGE (BM TERMINAL) |
|
(a) Make sure that there is no looseness at the locking part and the connecting part of the connectors. |
|
(b) Disconnect the A75 skid control ECU (brake actuator assembly) connector.
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
|
Tester Connection |
Condition |
Specified Condition |
|---|---|---|
|
A75-13 (BM) - Body ground |
Always |
11 to 14 V |
Text in Illustration
|
*a |
Front view of wire harness connector (to Skid Control ECU (Brake Actuator Assembly)) |
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (BM CIRCUIT) |
|
|
2. |
CHECK HARNESS AND CONNECTOR (GND2 TERMINAL) |
|
(a) Measure the resistance according to the value(s) in the table below. Standard Resistance:
Text in Illustration
|
|
| NG |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR (GND2 CIRCUIT) |
|
|
3. |
RECONFIRM DTC |
HINT:
These codes are stored when a problem is identified in the skid control ECU (brake actuator assembly).
The motor relay is in the skid control ECU (brake actuator assembly). Therefore, motor relay inspections and motor relay unit inspections cannot be performed. Be sure to check if any DTCs are output before replacing the brake actuator assembly.
(a) Reconnect the A75 skid control ECU (brake actuator assembly) connector.
(b) Clear the DTCs (See page
).
(c) Turn the ignition switch off.
(d) Start the engine.
(e) Drive the vehicle at a speed of 20 km/h (12 mph) or more for 30 seconds or more.
(f) Check if the same DTC is output (See page
).
|
Result |
Proceed to |
|---|---|
|
DTCs C142B, C146C and C146D are not output. |
A |
|
DTCs C142B, C146C and/or C146D are output. |
B |
HINT:
- If a speed signal of 6 km/h (4 mph) or more is input to the skid control ECU (brake actuator assembly), with the ignition switch to ON and the stop light switch assembly off, the ECU performs self diagnosis of the motor and solenoid circuits.
- If the normal system code is output (the trouble code is not output), slightly jiggle the connectors, wire harness, and fuses of the skid control ECU (brake actuator assembly). Make sure that no DTCs are output.
- If any DTCs are output while jiggling a connector or wire harness from the skid control ECU (brake actuator assembly), inspect and repair the connector or wire harness.
- The DTCs were probably output due to a bad connection of the connector terminal.
| A |
|
| B |
|
|
|