P1774
DTC P1774 Low Coast Brake Solenoid Valve FunctionDescription
^ 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.
^ This is not only caused by electrical malfunction (circuits open or shorted) but also by mechanical malfunction such as control valve sticking, improper solenoid valve operation.
SDT Reference Value in Data List Mode
On Board Diagnosis Logic
^ This is an OBD-II self-diagnostic item.
^ Diagnostic trouble code "P1774 LC/B SOLENOID FNCT" with SDT or 7th judgement flicker without SDT is detected under the following conditions.
^ When TCM detects that actual gear ratio is irregular, and relation between gear position and condition of ATF pressure switch 2 is irregular during depressing accelerator pedal. (Other than during shift change)
^ When TCM detects that relation between gear position and condition of ATF pressure switch 2 is irregular during releasing accelerator pedal. (Other than during shift change)
Possible Cause
^ Harness or connectors
(The solenoid and switch circuits are open or shorted.)
^ Low coast brake solenoid valve
^ ATF pressure switch 2
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 SDT
1. Start engine.
2. Accelerate vehicle to maintain the following conditions.
SLCT LVR POSI: "1" or "2" position
GEAR: 1st or "2nd" gear (LC/B ON/OFF)
3. Perform step "2" again.
4. Turn ignition switch "OFF", then perform step "1" to again.
5. Check "DTC check" mode for "AT" with SDT.
If DTC (P1772) is detected, go to P1772.
WITH GST
Follow the procedure "WITH SDT".
Diagnosis Procedure
Steps 1-4:
