Dtc P0731 - Mazda 6 2002 Workshop Manual

DTC P0731

DTC P0731 Gear 1 incorrect (Incorrect Gear Ratio Detected)
• PCM monitors revolution ratio of forward clutch drum revolution to differential gear case revolution when
the following monitoring conditions are met. If revolution ratio is below 2.157, PCM determines that there is
malfunction.
Monitoring condition:
— ATF temperature 20 ° ° ° ° C {68 ° ° ° ° F} or above.
— Driving in 1GR in D range.
— Engine run.
— Turbine speed within 225—4,988 rpm.
— Throttle opening angle 5.67% or above
DETECTION — Differential gear case (output) revolution speed 35 rpm or above.
CONDITION — Any of the following not generated: DTC P0500, P0706, P0707, P0708, P0712, P0713, P0715, P0751,
P0752, P0753, P0756, P0757, P0758, P0761, P0762, P0763, P0766, P0767, P0768, P0771, P0772,
P0773.
Diagnostic support note:
• This is a continuous monitor (CCM).
• MIL does not illuminate.
• HOLD indicator light flashes if PCM detects the above malfunction condition during first drive cycle.
• FREEZE FRAME DATA is not available.
• Pending code is not available.
• DTC stored in the PCM memory.
• ATF level low
• Deteriorated ATF
• Shift solenoid A stuck
• Pressure control solenoid stuck
POSSIBLE • Line pressure low
CAUSE • One-way clutch slipping
• Forward clutch slipping
• Control valve stuck
• Oil pump
• PCM malfunction
Diagnostic procedure
STEP
1 VERIFY RELATED REPAIR INFORMATION
AVAILABILITY
• Check for related Service Bulletins availability.
• Is any related repair information available?
2 CHECK ATF CONDITION
• Check ATF condition.
(See K–12 AUTOMATIC TRANSAXLE FLUID
(ATF) INSPECTION.)
• Is it okay?
3 CHECK ATF LEVEL
• Start engine.
• Warm up ATX.
• Is ATF level within specification?
(See K–12 AUTOMATIC TRANSAXLE FLUID
(ATF) INSPECTION.)
4 INSPECT SHIFT SOLENOID VALVE A
• Perform inspection of operation. (See
SOLENOID VALVE
• Verify the click sound of shift solenoid A when
applying B+ to transale connector terminal A.
• Was click heard from solenoids?
5 INSPECT LINE PRESSURE
• Start engine.
• Measure line pressures.
Specification
Idle: 330—470 kPa {3.4—4.7 kgf/cm
psi}
Stall: 1,160—1,320 kPa {11.9—13.4 kgf/cm
170—190 psi}
• Is line pressure within specification?
(See K–6 Line Pressure
K–70
ON-BOARD DIAGNOSTIC
INSPECTION
K–26
INSPECTION.)
2
, 49—66
2
,
Test.)
Yes Perform repair or diagnosis according to available repair
information.
No Go to net step.
Yes Go to net step.
No Replace ATF, then go to Step 8.
Yes Go to net step.
No Adjust ATF level, then go to Step 8.
Yes Go to net step.
No Replace solenoid that you could not hear click sound, then
go to Step 8.
(See K–28 SOLENOID VALVE REMOVAL/
INSTALLATION.)
Yes Go to net step.
No All ranges: Replace oil pump, then go to Step 8.
Any ranges: Replace control valve body, then go to Step 8.
(See K–34 CONTROL VALVE BODY
CONTROL VALVE BODY
A6E567001030W13
ACTION
REMOVAL, K–35
INSTALLATION.)