1994 MAZDA MX-5 Workshop Manual

K MECHANICAL SYSTEM TEST Evaluation of Stall Test 4bove specification Nithin specification In all ranges In D (Normal), and L ranges In D (Normal) range only In R range only 3elow specification Possible cause I Worn oil Dumo Oil leakage from oil pump, control Insufficient line pressure Direct clutch and overdrive one-way clutch sli~~ina Rear clutch slipping One-way clutch slipping Low and reverse brake slipping Front clutch slipping Perform road test to determine if this is caused by low and reverse brake or front clutch as follows: a) Effective engine braking in L range . . . . . . . . . . Front clutch b) No enaine brakina in L range . . . . . Low and reverse brake All ~hiftcont~elements within transmission are functioning normally Engine out of tune One-wav clutch sli~~ina within toraue converter Gartner Banana

MECHANICAL SYSTEM TEST TIME LAG TEST If the selector lever is shifted while the engine is idling, there will be a certain time lapse, or time lag, before shock is felt. This step checks this time lag for checking condition of the 1-2, N-R/2-3 and N-D L/ accumulators, front, rear and one-way clutches, 2nd brake band, and low and reverse brake. Preparation Perform the preparation procedure shown in the STALL TEST. (Refer to page K-22.) Procedure IDLE SPEED 1. Start the engine and check the idle speed in P range. (Refer to section F.) u Idle speed: 750--850 rpm 2. Shift from N range to D range. 3. Use a stopwatch to measure the time it takes from shifting until shock is felt. 4. Shift the selector to N and let the engine idle for 1 minute or more to cool the ATF. 5. Do the time lag test for the following shifts in the same manner. Make three measurements for each test and average the results. (1) N 4 D range (Normal mode) (2) N -+ D range (Hold mode) (3) N -+ R range .......................................... Specified time lag: N -t D range 0.5-46 second ..................... N -+ R range ... .............. 0.75-0.85 second Evaluation of Time Lag Test - I Condition N -c D (Hold) shifting More than specification Less than specification More than specification Less than specification N -+ R shifting I More than specification Less than specification Rear clutch slipping Excessive line pressure - lnsufficient line pressure Rear clutch slipping 2nd brake band slipping - 1-2 accumulator not operating properly Excessive line pressure lnsufficient line pressure Low and reverse brake slipping Front clutch slipping N-R/2-3 accumulator not operating properly Excessive line pressure K-25 Gartner Banana

K MECHANICAL SYSTEM TEST LINE PRESSURE TEST This test measures line pressures for checking the hydraulic components and inspecting for oil leakage. Preparation d 1. Perform the preparation procedure shown in the STALL TEST. (Refer to page K-22.) 2. Connect a tachometer to the engine. Warning Removing the square-head plug when the ATF is hot is dangerous. Hot ATF can come out of the opening and badly burn. Before removing the square-head plug, allow the ATF to cool. 3. Connect the SST to the line pressure inspection hole(s). Procedure 1. Start the engine and check the idle speed in P range. (Refer to section F.) Idle speed: 750--850 rpm * 2. Shift the selector lever to D range and read the line pressure at idle. Caution If the accelerator pedal is pressed for longer than 5 seconds while the brake pedal is pressed, the transmission could be damaged. Therefore, do steps 3 and 4 within 5 seconds of each oth- er. 3. Depress the brake pedal firmly with the left foot and gradually depress the accelerator pedal with the right foot. 4. Read the line pressure as soon as the engine speed becomes constant, then release the accelerator .- pedal. 5. Shift the selector to N and let the engine idle for 1 minute or more to cool the ATF. 6. Read the line pressure at idle and at the engine stall speed for each range in the same manner. Gartner Banana

MECHANICAL SYSTEM TEST K Specified line pressure: 7. Cool the transmission and reconnect the SST to the line pressure inspection hole. 8. Connect a vacuum pump to the vacuum diaphragm and place the pump inside the vehicle. 9. Shift the selector lever to R range. 10. Read the line pressure at idle as described below. Range D range S range L range R range Specified line pressure: Pressure kPa {kgflcm2, psi] Idle 285--362 i2.9-3.7,42-52) 785--921 (8.G9.4, 11 4--133) 295-392 {3.0-4.0,43--56) 775--970 (7.9--9.9, 1 1 S140) Vacuum Atmospheric pressure 1 400 mmHg (15.7 inHg} I 393490 (4.0-5.0,57-71) I Stall 79S912 18.1-9.3, 11 &I321 795--91 2 {8.1-9.3, 11 6--132) 883-1,078 l9.0-11 .O, 128-1 56) 1,972-2,167 (20.1-22.1,286--314) Line pressure kPa {kgf/cm2, psi) 883-1,078 {9.&11 .O, 128--156) 200 mmHg (7.87 inHg) - Evaluation of Line Pressure Test 687-784 17.0-4.0, 10-113) Below specification I Excessive line pressure Condition I Possible Cause In all ranges Worn oil pump Fluid leakage from the oil pump, control valve body, and/or transmission case Stuck pressure regulator valve Fluid leakage from the direct clutch and/or fourth gear band servo release side hydraulic circuit In D (Normal), S (Normal), and L Fluid leakage from the rear clutch hydraulic circuit ranaes I Stuck pressure modifier valve In S (Normal & Hold) and L ranges I Fluid leakage from the throttle backup valve hydraulic circuit In L and R ranges I Fluid leakage from the low and reverse hydraulic circuit In S range (Hold) In R range only Stuck throttle backup valve Stuck backup control valve Backup control function (electronic) not operating properly Stuck pressure modifier valve Stuck backup control valve Fluid leakage from the front clutch and/or 2nd band servo release side hydraulic circuit Below specification Excessive pressure In all ranges Same as Line Pressure Test Leaking or disconnected vacuum hose Leaking vacuum diaphragm Diaphragm rod too long Stuck vacuum throttle valve Stuck Dressure renulator valve I In S ranae (Hold) I Stuck pressure modifier valve Gartner Banana

K MECHANICAL SYSTEM TEST Incorrect line pressure with specified vacuum at vacuum diaphragm Condition No variation Possible Cause Missing diaphragm rod lncorrect variation (Above or below specification) Incorrect diaphragm rod length Stuck vacuum throttle valve Stuck pressure regulator valve Stuck Dressure regulator ~lua Gartner Banana

ROAD TEST K ROAD TEST A road test is necessary to inspect for problems in the different gear ranges. If a range or function tar- b geted by the road test is found to have any problem, refer to the ELECTRONIC SYSTEM COMPONENT segment or the TRANSMISSION, OIL COOLER, DRIVE PLATE, and SHIFT MECHANISM segments of this section. Do the road test only when the ATF is 50-80°C (1 22-1 76°F). D-RANGE TEST Shift Point, Shift Pattern, and Shift Shock 1. Shift the selector lever to D range and select the Normal mode. 2. Accelerate the vehicle with half-and wide open throttle opening. 3. Verify that 1-2, 2-3, and 3-4 upshifts, downshifts, and lockup are obtained. The shift points must be as shown in the D range (Normal) shift diagram. Note There is fourth gear is any of the following conditions. A The cruise control is operating, and there is an 8kmIh (5 mph} difference between the preset cruise speed and the vehicle speed. B The SET or RESUME switch is ON. There is no lockup when water temperature is below 50°C (1 22°F) or in the throttle valve closed posi- tion. 4. Check the upshifts for shift shock or slippage in the same manner. 5. While driving in overdrive, shift the selector lever to S range and verify that 4-3 downshift immediately occurs, then decelerate and verify that engine braking effect is felt in only third gear and 2nd gears. D-range (Normal) shift diagram p'yJ ..,,*sw.. LOCKUP AVAILABLE WHEN ACCELERATING AND CRUSING LOCKUP AVAILABLE WHEN COASTING 0 20 (1 2) 40 (25) 60 (37) 80 {50) 100 (63) 1 20 (75) 140 (87) 1 60 (99) VEHICLE SPEED kmlh {mph) Gartner Banana

ROAD TEST D range (Power) shift diagram = LOCKUP AVAILABLE WHEN ACCELERATING AND CRUSING LOCKUP AVAILABLE WHEN COASTING VEHICLE SPEED kmh (mph) 45UOKX-51 6. Select the Hold mode. 7. Accelerate the vehicle and check 2-3 up-and downshifts, verify that no 1st and no fourth gear is ob- tained, and verify that the 2-3 shift points are as shown in the D range (Hold) shift diagram. D-range (Hold) shift diagram 0 20 (1 2) 40 (25) 60 (37) 80 (50) 100 {63) 120 (75) 140 {87) 160 (99) VEHICLE SPEED kmlh (mph) Gartner Banana

ROAD TEST K Evaluation I No lockup shift Condition No 1-2 up or downshift No 2-3 up or downshift No 3-4 up or downshift I Stuck lockup control solenoid valve Stuck locku~ control valve Possible Cause Stuck 1-2 shift solenoid valve Stuck 1-2 shift valve Stuck 2-3 shift solenoid valve Stuck 2-3 shift valve Stuck 3-4 shift solenoid valve Stuck 3-4 shift valve Incorrect shift point I No enaine brakina effect I Worn clutches, brakes I Misadjusted throttle position sensor Sticking shift valves Excessive shift shock or slippage Noise and Vibration Drive the vehicle in fourth gear (lockup), fourth gear (no lockup), and third gear (Hold) and listen closely for any out of the ordinary noise or vibration. The torque converter, propeller shaft, and differential can be sources of abnormal noise and vibration if they are not functioning properly. Check these when searching for sources of noise and vibration. Stuck accumulators Stuck or no one-way check orifice Stuck 3-2 control solenoid valve Stuck 3-2 control valve Worn clutches, brakes, or one-way clutch Kickdown Drive the vehicle in fourth gear, third gear, and 2nd gear and check that kickdown occurs for 4-+3,4-+2, 4+1,3+2,3+1, 2+1, and that the shift points are as shown in the shift diagram. ,U (Refer to pages K-29, 30.) S-RANGE TEST Shift Pattern For this test it is not necessary to inspect shift shock and shift points, since they are almost exactly the same as those for the D-range test. However, in the D-range (Normal) shift diagram, the shift points are different. In S range, the shift patterns for Normal mode are the same. 1. Shift the selector lever to S range and select the Normal mode. 2. Accelerate the vehicle and verify that 1-2 and 2-3 up-and downshifts are obtained, and that no fourth gear and no lockup (below approx. 100 kmlh (63 mph}) are obtained. 3. While driving in S range (Normal mode) and third gear, select the Hold mode and verify that third gear is held until ihe 3-2 downshift point as shown in the S range (Hold) shift diagram is achieved. 4. Accelerate the vehicle in S range (Hold mode) and verify that 2nd gear is held. S-range (Power) shift diagram LOCKUP AVAILABLE WHEN ACCELERATING AND CRUSING LOCKUP AVAILABLE WHEN COASTING -. - VEHICLE SPEED kmlh (rnph} Gartner Banana