Toyota Tacoma 2015-2018 Service Manual: Open in ABS Solenoid Relay Circuit (C146E,C146F)

Toyota Tacoma 2015-2018 Service Manual / Brake Control / Dynamic Control Systems / Vehicle Stability Control System(for Vacuum Brake Booster) / Open in ABS Solenoid Relay Circuit (C146E,C146F)

DESCRIPTION

The ABS solenoid relay supplies power to the ABS solenoid and TRAC solenoid.

The solenoid relay is turned on 1.5 seconds after the ignition switch is turned ON, and is turned off if an open or short in the solenoid is detected by the self diagnosis performed when the engine starts running.

The ABS solenoid relay is housed in the skid control ECU in the actuator assembly.

DTC No.	Detection Item	DTC Detection Condition	Trouble Area
C146E	Open in ABS Solenoid Relay Circuit	Either of the following is detected: When voltage at terminal +BS is 9.5 V or higher and solenoid relay is ON, relay contact is OFF continuously for 0.22 seconds or more. When solenoid relay is turned on and voltage at +BS terminal is below 9.5 V, relay contact does not turn on after 0.22 seconds or more.	ABS NO. 2 fuse Wire harness or connector Skid control ECU (Brake actuator assembly)
C146F	Short in ABS Solenoid Relay Circuit	Immediately after ignition switch turned ON and solenoid relay is OFF, relay contact is ON continuously for 4.5 seconds or more.	Skid control ECU (Brake actuator assembly)

HINT:

DTC will be output when conditions for either of the patterns in the table above are met.

WIRING DIAGRAM

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 C146E and/or C146F, inspect and repair the trouble areas indicated by C1241 and/or C1417 first.

for C1241: (See page )
for C1417: (See page )

PROCEDURE

1.	CHECK TERMINAL VOLTAGE (+BS TERMINAL)

(a) Turn the ignition switch off.

(b) Make sure that there is no looseness at the locking part and the connecting part of the connectors.

(d) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Condition	Specified Condition
S1-38 (+BS) - Body ground	Always	11 to 14 V

Text in Illustration

*a	Front view of wire harness connector (to Skid Control ECU [Brake Actuator Assembly])

REPAIR OR REPLACE HARNESS OR CONNECTOR (+BS CIRCUIT)

2.	CHECK HARNESS AND CONNECTOR (GND1 TERMINAL)

(a) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection	Condition	Specified Condition
S1-25 (GND1) - Body ground	Always	Below 1 Ω

Text in Illustration

*a	Front view of wire harness connector (to Skid Control ECU [Brake Actuator Assembly])

REPAIR OR REPLACE HARNESS OR CONNECTOR (GND1 CIRCUIT)

3.	RECONFIRM DTC

HINT:

These codes are detected when a problem is determined in the skid control ECU (brake actuator assembly).

The solenoid circuits are in the skid control ECU (brake actuator assembly).

Therefore, solenoid circuit inspection and solenoid unit inspection cannot be performed.

Be sure to check if any DTCs are output before replacing the skid control ECU (brake actuator assembly).

(a) Reconnect the S1 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 recorded (See page Result Result ).

Result

Result	Proceed to
DTC C146E and/or C146F are not output	A
DTC C146E and C146F 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 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.

USE SIMULATION METHOD TO CHECK

REPLACE BRAKE ACTUATOR ASSEMBLY

Unusual Bank Angle Detected (C1440)

DESCRIPTION If the skid control ECU (brake actuator assembly) determines that the vehicle is being driven at a steep bank angle, the skid control ECU (brake actuator assembly) stores DTC C1440 wh ...

Invalid Data Received from Deceleration Sensor (C1442,C1443)

DESCRIPTION The airbag sensor assembly has a built-in yaw rate and acceleration sensor. The skid control ECU (brake actuator assembly) receives signals from the yaw rate and acceleration sensor (a ...

Other materials:

How To Proceed With Troubleshooting
CAUTION / NOTICE / HINT HINT: Use these procedures to troubleshoot the lighting system. *: Use the Techstream. PROCEDURE 1. VEHICLE BROUGHT TO WORKSHOP NEXT 2. ...

Open Circuit in IG1/IG2 Power Source Circuit (C1242)
DESCRIPTION If there is a problem with the skid control ECU (master cylinder solenoid) power supply circuit, the skid control ECU outputs the DTC and prohibits operation under the fail safe function. If the voltage supplied to terminal IG1 and/or IG2 is not within the DTC detection threshold ...

Zero Point Calibration of Yaw Rate Sensor Undone (C1210,C1336)
DESCRIPTION The skid control ECU (master cylinder solenoid) receives signals from the yaw rate and acceleration (airbag sensor assembly) via the CAN communication system. The airbag sensor assembly has a built-in yaw rate and acceleration sensor and detects the vehicle's condition using 2 ...