Toyota Sienna Service Manual: Open in Pump Motor Circuit

Toyota Sienna Service Manual / Brake control / Anti-lock brake system / Diagnostic trouble code chart / Open in Pump Motor Circuit

DTC C1251/51 Open in Pump Motor Circuit

DESCRIPTION

The motor relay (semiconductor relay) is housed in the brake actuator assembly and drives the pump motor based on a signal from the skid control ECU.

Open in Pump Motor Circuit

WIRING DIAGRAM

Refer to DTCs C0273/13 and C0274/14 (See page BC-31).

INSPECTION PROCEDURE

HINT: After step 1 is complete, start the inspection from step 2 when using the intelligent tester, and from step 3 when not using the intelligent tester.

1 INSPECT SKID CONTROL ECU (GND TERMINAL CONTINUITY)

INSPECT SKID CONTROL ECU (GND TERMINAL CONTINUITY)

(a) Disconnect the skid control ECU connector.

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

Standard resistance

2 PERFORM ACTIVE TEST BY INTELLIGENT TESTER (ABS MOTOR RELAY)

(a) Reconnect the skid control ECU connector.

(b) Connect the intelligent tester to the DLC3.

(d) Start the engine.

(e) Select the ACTIVE TEST mode on the intelligent tester.

ABS:

(f) Check operating sound of the ABS motor when operating it with the intelligent tester.

OK: The operating sound of the ABS motor is heard.

3 RECONFIRM DTC

(a) Clear the DTCs (See page BC-10).

(b) Start the engine.

(d) Check that the same DTC is recorded (See page BC- 10).

HINT:

Reinstall the sensors, connectors, etc. and restore the vehicle to its prior condition before rechecking for DTCs.
If a speed signal of 6 km/h (4 mph) or more is input to the skid control ECU, with the ignition switch on and the stop light switch off, the ECU performs selfdiagnosis of the motor and solenoid circuits.

Result

HINT:

If any DTCs are output while jiggling a connector or wire harness of the brake actuator (skid control ECU), inspect and repair the connector or wire harness.
If the normal system code is output, slightly jiggle the connectors, wire harnesses, and fuses of the brake actuator assembly. Make sure that no DTCs are output.
These DTCs may be stored due to a malfunction in the connector terminal connection, etc.

REPLACE BRAKE ACTUATOR ASSEMBLY

Open in Stop Light Switch Circuit

DTC C1249/49 Open in Stop Light Switch Circuit DESCRIPTION This skid control ECU inputs the stop light switch signal and detects the status of brake operation. The skid control ECU has an open ...

ABS Warning Light Remains ON

DESCRIPTION If any of the following is detected, the ABS warning light remains on. The skid control ECU connectors are disconnected from the skid control ECU. There is a malfunction in the s ...

Other materials:

Inspection
1. V (a) Inspect VSV operation. (1) Using an ohmmeter, measure the resistance according to the value(s) in the table below.V Standard resistance If the result is not as specified, replace the vsv. (B) inspect the vsv for ground. (1) Using an ohmmeter, measure the resistance accordin ...

Rear Air Conditioning Control Panel Circuit
DESCRIPTION This is the rear A/C system control signal circuit as well as the power supply circuit of the rear A/C control assembly. Pulse signals regarding rear A/C control panel switch operation are transmitted between the A/C amplifier and rear A/C control assembly. WIRING DIAGRAM ...

Monitor drive pattern
1. MONITOR DRIVE PATTERN FOR ECT TEST (a) Perform this drive pattern as one method to simulate the detection conditions of the ECT malfunctions. (The DTCs may not be detected due the actual driving conditions. And some codes may not be detected through this drive pattern.) HINT: Preparation f ...