P1759
DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTIONDescription
- 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.
- 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.
CONSULT-II Reference Value:
On Board Diagnosis Logic
- This is an OBD-II self-diagnostic item.
- Diagnostic trouble code "P1759 FR/B SOLENOID FNCT" with CONSULT-II 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 1 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 1 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.)
- Front brake solenoid valve
- ATF pressure switch 1
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-II
1. Start engine.
2. Accelerate vehicle to maintain the following conditions.
ACCELE POS: 1.5/8 - 2.0/8
Selector lever: "D" position
Gear position: 3rd -> 4th Gear (FR/B ON/OFF)
Driving location: Driving the vehicle uphill (increased engine load) will help maintain the driving conditions required for this test.
3. Perform step "2" again.
4. Turn ignition switch "OFF", then perform step "1" to "3" again.
5. Check "SELF-DIAG RESULTS" mode for "A/T" with CONSULT-II.
If DTC (P1759) is detected, refer to AT-144, "Diagnostic Procedure".
If DTC (P1757) is detected, go to AT-142, "Diagnostic Procedure". P1757
If DTC (P1841) is detected, go to AT-162, "Diagnostic Procedure". P1841
WITH GST
Follow the procedure "With CONSULT-II".
Diagnostic Procedure
1. CHECK INPUT SIGNALS
With CONSULT-II
1. Start engine.
2. Select "SELECTION FROM MENU" in "DATA MONITOR" mode for "A/T" with CONSULT-II.
3. Drive vehicle in the "D" position (3rd -> 4th gear), and confirm the ON/OFF actuation of the "ATF PRES SW 1" and electrical current value of "FR/B SOLENOID".
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-169, "MAIN POWER SUPPLY AND GROUND CIRCUIT". Main Power Supply and Ground Circuit
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. DETECT MALFUNCTIONING ITEM
Check the following items:
- The 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 "DTC Confirmation Procedure".
- Refer to AT-143, "DTC Confirmation Procedure".
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.