P1757

DTC P1757 FRONT BRAKE SOLENOID VALVE

Description
Front brake solenoid valve is controlled by the TCM in response to signals sent from the PNP switch, vehicle speed sensor and accelerator pedal position sensor (throttle position sensor). Gears will then be shifted to the optimum position.

CONSULT-III Reference Value in Data Monitor Mode:

On Board Diagnosis Logic
Diagnostic trouble code "P1757 FR/B SOLENOID/CIRC" with CONSULT-III or 6th judgment flicker without CONSULT-III is detected under the following conditions.
^ When TCM detects an improper voltage drop when it tries to operate the solenoid valve.
^ When TCM detects as irregular by comparing target value with monitor value.

Possible Cause
^ Harness or connectors
(Solenoid circuit is open or shorted.)
^ Front brake solenoid valve

DTC Confirmation Procedure

CAUTION: Always drive vehicle at a safe speed.

NOTE: If "DTC Confirmation Procedure" has been previously performed, always turn ignition switch OFF and wait at least 10 seconds before performing the next test.

After the repair, perform the following procedure to confirm the malfunction is eliminated.

WITH CONSULT-III
1. Turn ignition switch ON.
2. Select "SELECTION FROM MENU" in "DATA MONITOR" mode for "TRANSMISSION" with CONSULT-III and check monitor "ACCELE POSI", "SLCT LVR POSI" and "GEAR".
3. Touch "START".
4. Start engine.
5. Drive vehicle and maintain the following conditions for at least 5 consecutive seconds.
ACCELE POSI: 1.5/8 - 2.0/8
SLCT LVR POSI: "D" position
GEAR: "3" ---> "4" (FR/B ON/OFF)
Driving location: Driving the vehicle uphill (increased engine load) will help maintain the driving conditions required for this test.
6. If DTC is detected go to "Diagnosis Procedure".

WITH GST
Follow the procedure "WITH CONSULT-III".

Diagnosis Procedure

1. CHECK INPUT SIGNAL

WITH CONSULT-III
1. Turn ignition switch ON.
2. Select "MAIN SIGNALS" in "DATA MONITOR" mode for "TRANSMISSION" with CONSULT-III.
3. Start engine.
4. Readout the value of "FR/B SOLENOID" while driving.





OK or NG
OK >> GO TO 4.
NG >> GO TO 2.

2. CHECK TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.

3. DETECT MALFUNCTIONING ITEM
Check A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace the control valve with TCM.
NG >> Repair or replace damaged parts.

4. CHECK DTC
Perform AT-106, "DTC Confirmation Procedure". P0717
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.