P1772

DTC P1772 LOW COAST BRAKE SOLENOID VALVE

Description
Low coast brake solenoid valve is turned ON or OFF 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-II Reference Value:

On Board Diagnosis Logic
^ This is an OBD-II self-diagnostic item.
^ Diagnostic trouble code "P1772 LC/B SOLENOID/CIRC" with CONSULT-II or 7th judgement flicker without CONSULT-II is detected when TCM detects an improper voltage drop when it tries to operate the solenoid valve.

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

DTC Confirmation Procedure

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-II





1. Turn ignition switch ON.
2. Select "SELECTION FROM MENU" in "DATA MONITOR" mode for "A/T" with CONSULT-II and check monitor "MANU MODE SW" and "GEAR".
3. Touch "START".
4. Start engine.
5. Drive vehicle and maintain the following conditions for at least 5 consecutive seconds.
MANU MODE SW: ON
GEAR: "1" or "2" (LC/B ON/OFF)
6. If DTC is detected, go to AT-163, "Diagnostic Procedure".

With GST
Follow the procedure "WITH CONSULT-II".

Diagnostic Procedure

1. CHECK INPUT SIGNAL

With CONSULT-II








1. Turn ignition switch ON.
2. Select "SELECTION FROM MENU" in "DATA MONITOR" mode for "A/T" with CONSULT-II.
3. Start engine.
4. Read out the value of "ON OFF SOL" 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. Refer to AT-179, "MAIN 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-162, "DTC Confirmation Procedure".
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.