LEMON Manuals: Even more car manuals for everyone
Home >> Mazda >> 2002 >> Tribute LX, 4WD >> Repair and Diagnosis >> External Pages >> Different car >> Section 35 (Automatic Transmission - Diagnosis [GF4A-El]) >> Diagnostic Tests >> DTC P0731: Incorrect 1ST Gear Ratio >> Diagnostic Procedure

Diagnostic Procedure

WARNING: This page is about a different car, the 2002 Mazda 626 and 2001 Mazda 626. However, it is still accessible from the selected car via links, so may be relevant.
  1. Record FREEZE FRAME PID data. Check for related service bulletins. Repair as necessary. Turn ignition switch to OFF position. Check ATF condition. If ATF is milky (contaminated with water) or reddish brown (deteriorated fluid), replace fluid and go to next step. If ATF condition is okay, start engine and warm to normal operating temperature. Check ATF level. Add fluid as necessary. If ATF level is okay, go to next step.
  2. Start engine and perform line pressure test in all gears. See HYDRAULIC PRESSURE TESTS  under PERFORMANCE TESTS. If line pressure is low in all or any gears, see HYDRAULIC PRESSURE TEST RESULTS . If line pressure is within specification for all gears, perform stall speed test with gearshift lever in "D" position. See STALL SPEED TEST . Stall speed should be 2000-2500 RPM. If stall speed is within specification, check all connectors, terminals and wiring harnesses for intermittent concern. If stall speed is not within specification, go to next step.
  3. Turn ignition switch to OFF position. Connect scan tool to DLC. Start engine. Using scan tool, access VSS, TR, TSS and TP V PIDs from PID/DATA MONITOR & RECORD menu. Road test vehicle in "D" position (O/D OFF switch off) at 12 MPH, while monitoring TSS PID. The following PID values must be met during road test:
    • VSS PID value should be 12 MPH.
    • TR PID value should be O/D.
    • 1GR PID should be indicated.
    • TP V PID value should be 1.4-2.4 volts.

    TSS PID value should be about 2100 RPM. If TSS PID value is as specified, check connectors, terminals and wiring harnesses for intermittent concern. If TSS PID value is not as specified, perform solenoid "click" test. See SOLENOID VALVES  under COMPONENT TESTS. If all solenoids "click" when actuated, replace valve body. See VALVE BODY under COMPONENT DISASSEMBLY & REASSEMBLY in appropriate OVERHAUL article. If any solenoid does not "click" when actuated, replace inoperative solenoid(s).

  4. Start engine. Warm engine and transaxle to normal operating temperature. Using scan tool, access VSS, TP V and TR PIDs from PID/DATA MONITOR & RECORD menu. Road test vehicle to achieve VSS PID value 5-30 MPH and TR PID value of O/D, and TP V PID value 1.1 volts or more for 15 seconds or more. Bring vehicle to a complete stop and repeat PID/DATA MONITOR & RECORD procedure 5 times. Go to next step.
  5. Bring vehicle to a gradual stop. Perform self-test on PCM and ensure serviced DTC does not repeat. If serviced DTC resets, repeat previous step. If serviced DTC resets again, replace PCM.
scientia non olet · About LEMON Manuals