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Automatic Transmission Preliminary Inspection




AUTOMATIC TRANSMISSION PRELIMINARY INSPECTION

The following items must be checked prior to beginning the diagnostic procedures:

Determine Customer Concern

NOTE:Some transmission conditions can cause engine concerns. An electronic pressure control short circuit can cause engine misfiring. The torque converter clutch not disengaging stalls the engine.Determine customer concerns relative to vehicle use and dependent driving conditions, paying attention to the following items:

- Hot or cold vehicle operating temperature
- Hot or cold ambient temperatures
- Type of terrain
- Vehicle loaded/unloaded
- City/highway driving
- Upshift
- Downshift
- Coasting
- Engagement
- Noise/vibration check for dependencies, either rpm dependent, vehicle speed dependent, shift dependent, gear dependent, range dependent, or temperature dependent.

Check Fluid Level and Condition

Fluid Level Check

CAUTION:The vehicle should not be driven if the fluid level indicator shows the fluid below the do not drive mark or internal failure could result.
NOTE:If the vehicle has been operated for an extended period of time at highway speeds, city traffic, hot weather, or pulling a trailer, the fluid needs to cool down to obtain an accurate reading.The fluid level reading on the indicator differs from operating and ambient temperatures. The correct reading should be within the normal operating range. Under normal circumstances, check the fluid level during normal maintenance. If the transmission starts to slip, shift slowly, or has signs of fluid leaking, check the fluid level and repair any leak(s).
1. With the transmission in (P) Park, the engine at idle, foot pressed on the brake, move the range selector lever through each gear and allow engagement of each gear. Place the selector lever in the PARK position.

2. Wipe the fluid level indicator cap and remove the indicator.

3. Wipe the fluid level indicator with a clean cloth.

4. Install the fluid level indicator back in the oil filler tube until it is fully seated, then remove the fluid level indicator. The fluid level should be within the normal operating range.










High Fluid Level

A fluid level that is too high may cause the fluid to become aerated due to the churning action of the rotating internal parts. This causes erratic control pressure, foaming, loss of fluid from the vent tube and possible transmission malfunction and/or damage. If an overfill reading is indicated, see Service and Repair.

Low Fluid Level

A low fluid level could result in poor transmission engagement, slipping, malfunction and/or damage. This could also indicate a leak in one of the transmission seals or gaskets.

Adding Fluid

CAUTION:The use of any other type of transmission fluid than specified could result in transmission malfunction and/or damage.Before adding fluid be sure that the correct type is being used. See 05-50 GENERAL SPECIFICATIONS.
If fluid needs to be added, add fluid in 0.25L (1/2 pint) increments through the filler tube. Do not overfill the fluid. For fluid type, see the specification chart.

Fluid Condition Check

1. Check the fluid level.

2. Observe the color and the odor. The color under normal circumstances should be dark reddish, not brown or black.

3. Hold the fluid level indicator over a white facial tissue and allow the fluid to drip onto the facial tissue and examine the stain.

4. If evidence of solid material is found, remove the oil pan for further inspection.

5. If the stain is a foamy pink color, this may indicate coolant in the transmission. Inspect the engine cooling system.

6. If fluid contamination or transmission failure is confirmed by the sediment in the bottom of the oil pan, the transmission may need to be replaced and torque converter and cooling lines flushed.

7. Perform diagnostic checks and adjustments; see - Symptom Troubleshooting Chart - Automatic Transmission.

Road Testing Vehicle

NOTE:Always drive the vehicle in a safe manner according to driving conditions and obey all traffic laws.
NOTE:Transmission with identification tag IL5P-DA or IL5P-EA only, will have adaptive shift strategy.
NOTE:When the battery has been disconnected, or a new battery installed, certain transmission operating parameters may be lost. The powertrain control module (PCM) must relearn these parameters. During this learning process you may experience slightly firm shifts, delayed, or early shifts. This operation is considered normal and will not affect the function of the transmission. Normal operation will return once these parameters are stored by the PCM.The Shift Point Road Test and Torque Converter Clutch Operation Test provide diagnostic information on transmission shift controls and torque converter operation.

Shift Point Road Test

This test verifies that the shift control system is operating properly.

1. Bring engine and transmission up to normal operating temperature.

2. Operate vehicle with transmission selector in D range.

3. Apply minimum throttle and observe speeds at which upshift occurs and torque converter engages. See the following Shift Speeds chart.

4. Stop the vehicle. Press transmission control switch and overdrive off switch (O/D OFF) to activate D range. Repeat Step 3. Transmission will make all upshifts except 4-5 and torque converter clutch apply should occur above 46 km/h (28 mph).

5. Press accelerator pedal to floor, wide open throttle (WOT). Transmission should shift from third to second, or third to first, depending on vehicle speed, and torque converter clutch should release.

6. With vehicle speed above 48 km/h (30 mph), move the selector lever from D range to 1 range (LOW) and release accelerator pedal. Transmission should immediately downshift to third gear. When vehicle speed drops below 32 km/h (20 mph), transmission should downshift into first gear.

7. If transmission fails to upshift/downshift or torque converter clutch does not apply/release, see - Symptom Troubleshooting Chart - Automatic Transmission.
Shift Speeds





NOTE:Shift speed ranges are approximate for all applications.
Torque Converter Diagnosis

Prior to torque converter replacement, all diagnostic procedures must be followed. This prevents the unnecessary replacement of good torque converters. Only after a complete diagnostic evaluation can the decision be made to replace the torque converter.
Begin with the normal diagnostic procedures as follows:

1. Preliminary Inspection.

2. Know and understand the customer's concern.

3. Perform the Torque Converter Operation Test. See.

4. Perform diagnostic procedures.

- Perform on-board diagnostics with IDS or equivalent tester. See Automatic Transmission Diagnosis.
- Repair all non-transmission related DTCs first.
- Repair all transmission DTCs.
- Rerun on-board diagnostic to verify repair.
- Perform Line Pressure Test. See Automatic Transmission Special Testing Procedure.
- Perform Stall Speed Test. See Automatic Transmission Special Testing Procedure.
- Perform Diagnosis by Symptom Procedure. See - Symptom Troubleshooting Chart - Automatic Transmission.

Torque Converter Operation Test

This test verifies that the torque converter clutch control system and the torque converter are operating properly.

1. Perform Quick Test; see - On - Board Diagnostic Tests.

2. Connect a tachometer to the engine.

3. Bring the engine to normal operating temperature by driving the vehicle at highway speeds for approximately 15 minutes in D (Overdrive) position.

4. After normal operating temperature is reached, maintain a constant vehicle speed of about 80 km/h (50 mph) and tap brake pedal with the left foot.

- Engine rpm should increase when brake pedal is tapped, and decrease about five seconds after pedal is released.
- If this does not occur, see - Symptom Troubleshooting Chart - Automatic Transmission Torque Converter Operation Concerns.

5. If the vehicle stalls in D (Overdrive) or manual 2 at idle with vehicle at a stop, move the transmission range selector lever to manual 1 position.

- If the vehicle stalls, see - Symptom Troubleshooting Chart - Automatic Transmission Torque Converter Operation Concerns. Repairs required.
- If the vehicle does not stall in D (Overdrive), see - Symptom Troubleshooting Chart - Automatic Transmission.

Visual Inspection

This inspection will identify modifications or additions to the vehicle operating system that may affect diagnosis. Inspect the vehicle for non-Mazda factory add-on devices such as:

- Electronic add-on items:

- air conditioning
- generator (alternator)
- engine turbo
- cellular telephone
- cruise control
- CB radio
- linear booster
- backup alarm signal
- computer
- Vehicle modification:
These items, if not installed properly, affect the powertrain control module (PCM), or transmission function. Pay particular attention to add-on wiring splices in the PCM harness or transmission wiring harness, abnormal tire size, or axle ratio changes.

- Leaks. See Automatic Transmission Special Testing Procedure.
- Proper linkage adjustments. See Adjustments.

Shift Linkage Check

NOTE:Some vehicles equipped with automatic transmissions have wiring to the clutch pedal position (CPP) switch. If the CPP wiring harness and jumper plug are present, see - Symptom Troubleshooting Chart - Automatic Transmission External Controls.Check for a misadjustment in shift linkage by matching the detents in the transmission range selector lever with those in the transmission. If they match, the misadjustment is in the indicator. Do not adjust the shift linkage.
Hydraulic leakage at the manual control valve can cause delay in engagements and/or slipping while operating if the linkage is not correctly adjusted. See Adjustments for shift linkage adjustment.

Perform On-Board Diagnostics

After a road test, with the vehicle warm and before disconnecting any connectors, perform the Quick Test using IDS or equivalent tester. See - On - Board Diagnostic Tests for diagnosis and testing of the powertrain control system.

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