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 "FRB SOLENOID FNCT" with CONSULT-II or P1759 without 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 "AT" with CONSULT II. If DTC (P1759) is detected, refer to "Diagnostic Procedure" below. If DTC (P1757) is detected, go to "Diagnostic Procedure" below. If DTC (P1841) is detected, go to "Diagnostic Procedure" below.
WITH GST
Follow the procedure "With CONSULT-II".
Diagnostic Procedure
1. INPUT SIGNALS
With CONSULT-II
1. Start engine.
2. Select "ECU INPUT SIGNALS" or "MAIN SIGNALS" 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".
With GST
Follow the procedure "With CONSULT-II".
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2. CHECK TCM
Perform TCM input/output signal inspection.
OK or NG
OK >> GO TO 4.
NG >> GO TO 3.
3. DETECT MALFUNCTIONING ITEM
Check the following items:
- Power supply and ground circuit for TCM.
- The A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace the transmission assembly.
NG >> Repair or replace damaged parts.
4. CHECK DTC
Perform DTC Confirmation Procedure.
OK or NG
OK >> INSPECTION END
NG >> GO TO 2.