Mazda 626 - Owner Maintenance

ON-BOARD DIAGNOSTIC
DTC P0742
DTC P0742 Torque converter clutch (TCC) stuck ON
DETECTION
CONDITION
• All of following conditions satisfied under each of following throttle conditions.
— ATF temperature 20 ° C {68 ° F} or above.
— Driving in 4GR at D range.
— Engine speed 450 rpm or above.
— Turbine speed within 225—4,988 rpm.
— Vehicle speed below 70 km/h {43 mph}.
— Torque converter clutch (TCC) no operation
— Difference between engine speed and turbine speed below 50 rpm
— Throttle conditions
— DTC P0734 not output.
• Throttle conditions
— Throttle opening angle within 3.125—6.25 % and 3 seconds or more have passed.
— Throttle opening angle above 6.25 % and 10 seconds or more have passed.
— Throttle opening angle closed throttle position and 10 seconds or more have passed.
POSSIBLE
CAUSE
• ATF level low
• Deteriorated ATF
• Shift solenoids A, B, C, D, E, and pressure control solenoid stuck
• Line pressure low
• 2-4 brake band slipping
• 3-4 clutch slipping
• Control valve stuck
• PCM malfunction [
Diagnostic procedure
STEP
INSPECTION ACTION
1
VERIFY RELATED REPAIR INFORMATION
AVAILABILITY
• Check for related Service Information
availability.
• Is any related Service Information available?
Yes Perform repair or diagnosis according to available repair
information.
• If vehicle is not repaired, go to next step.
No
Go to next step.
2
CHECK ATF CONDITION
• Turn ignition key to OFF.
• Check ATF condition.
— Clear red: Normal
— Milky: Water mixed in fluid
— Reddish brown: Deteriorated ATF
• Is it okay?
(See K2-28 AUTOMATIC TRANSAXLE FLUID
(ATF) INSPECTION, Automatic Transaxle Fluid
(ATF) Condition Inspection.)
Yes Go to next step.
No
If ATF color milky or reddish brown, replace ATF, then go
to Step 4.
(See K2-29 AUTOMATIC TRANSAXLE FLUID (ATF)
REPLACEMENT.)
3
CHECK ATF LEVEL
• Start engine.
• Warm up ATX.
• Is ATF level within specification?
(See K2-28 AUTOMATIC TRANSAXLE FLUID
(ATF) INSPECTION, Automatic Transaxle Fluid
(ATF) Level Inspection.)
Yes
Go to next step.
No Adjust ATF level, then go to Step 6.
(See K2-28 AUTOMATIC TRANSAXLE FLUID (ATF)
INSPECTION, Automatic Transaxle Fluid (ATF) Level
Inspection.)
4
INSPECT LINE PRESSURE
• Start engine.
• Measure line pressure.
Specification
Idle: 334—470 kPa {3.4—4.8 kgf/cm2,
49—68 psi}
Stall: 1,158—1,323 kPa {11.8—13.5 kgf/cm2,
168—191 psi}
• Is line pressure within specification?
(See K2-21 MECHANICAL SYSTEM TEST, Line
Pressure Test.)
Yes Go to next step.
No • All ranges: Replace oil pump or control valve body,
then go to Step 6.
(See K2-46 CONTROL VALVE BODY REMOVAL.)
(See K2-46 CONTROL VALVE BODY INSTALLATION.)
(See ATX Workshop Manual FN4A-EL [1623-10-98E].)
• Any ranges: Replace ATX, then go to Step 6.
(See K2-41 AUTOMATIC TRANSAXLE (ATX)
REMOVAL/INSTALLATION.)
K2-92