Initial Inspection

Preliminary Inspection
The following items must be checked before proceeding:

Know and Understand the Concern
In order to properly diagnose a concern you must first understand the customer complaint or condition. Customer contact may be required in order for the technician to begin to verify the concern. You must understand the conditions as to when the concern occurs. For example:
- hot or cold vehicle temperature
- hot or cold ambient temperature
- vehicle driving conditions
After understanding when and how the concern occurs then proceed to verifying the concern.

Verification of Condition
This section provides information which must be used in both determining the actual cause of customer concerns and performing the appropriate service procedures.
The following procedures must be used when verifying customer concerns for the AX4N transaxle:

Required Equipment

CAUTION: To properly diagnose an AX4N transaxle, the Rotunda Transmission Tester (007-00085) must have been updated for AX4N compatibility. The Rotunda AX4N Transmission Tester Update (007-00105) includes internal software and related components and a new cable and overlay. Inspect your tester for the "AX4N Compatible" label located near the tester's cable connector. If the label is missing, do not use the tester to diagnose the AX4N transaxle. Contact Rotunda Equipment or supplier as listed in instruction manual for information on how to have the tester updated.

- Rotunda Transmission Tester 007-00085
- Rotunda AX4N Transmission Tester Update 007-00105
- Rotunda New Generation Star (NGS) Tester 007-00500 or equivalent
- Rotunda Digital Volt-Ohmmeter 014-00407 or equivalent
- Rotunda Transmission Range (TR) Sensor Cable (MLPS Cable) 007-00086 or 007-00111 or equivalent, used with Transmission Tester 007-00085
- Rotunda 104-Pin Breakout Box 014-00950 or equivalent
- Transmission Range (TR) Sensor (MLPS) Alignment Tool T92P-70010-AH

Determine Customer Concern
- 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

Note: If noise/vibration, check for dependencies, either rpm dependent, vehicle speed dependent, shift dependent, gear dependent, range dependent or temperature dependent.

Note: Some AX4N transaxle conditions may cause engine concerns. The torque converter clutch not disengaging will stall the engine.

Check Fluid Level and Condition

Fluid Level Check

Note: If the vehicle has been operating for an extended period at high speeds or in city traffic during hot weather or pulling a trailer, the engine should be turned off for about 30 minutes to allow the fluid to cool before checking.

It is preferable to check the transmission fluid level at normal operating temperature after approximately 32 kilometers (20 miles) of driving. However, if necessary, you can check the fluid level without having to drive 32 kilometers (20 miles) to obtain normal operating temperature if the outside temperature is above 10�C (50�F).

CAUTION: Your vehicle should not be driven if the fluid level is below the bottom hole on the fluid level indicator and the outside temperature is above 10� C (50�F).

Fluid Condition Check
- Make the normal fluid level check as outlined previously under Check Fluid Level and Condition.
- Observe the color and odor of the fluid. It should be red, not brown or black. The odor may indicate an overheating condition or a clutch disc or band failure.
- Use a clean lint-free cloth and wipe the fluid level indicator. Examine the stain for evidence of solid particles and for engine coolant signs (gum or varnish on the fluid level indicator).
- If particles are present in the fluid or there is evidence of engine coolant or water, the transaxle must be removed for further inspection.
- If fluid contamination or transaxle failure is confirmed by further evidence of coolant or excessive particles in the transaxle pan, the transaxle must be disassembled and completely cleaned and serviced. This includes cleaning and flushing the torque converter (7902) and transaxle cooling system.
- During disassembly and assembly, all overhaul checks and adjustments of clearances and end play must be made. After the transaxle has been serviced, all diagnostic tests and adjustments listed in the diagnostic charts must be completed to make sure that the problem has been corrected.

Shift Point Road Test
Road Testing

Torque Converter Clutch Operation Tests
Torque Converter Clutch Operation Tests

Visual Inspection

This inspection will identify modifications or additions to the vehicle operating system that may affect diagnosis.
a. Vehicle modification.
b. Electronic add-on items:
- air conditioning
- generators (alternators)
- engine turbos
- cellular telephones
- cruise controls
- CB radios
- linear boosters
- backup alarm signals
- computers
c. Leaks - Refer to Special Testing Procedures.
d. Proper linkage adjustments.
e. These items, if not installed properly, will affect powertrain control module or transaxle function. Pay particular attention to add-on wiring splices in the powertrain control module harness or transmission wiring harness, abnormal tire size, or axle ratio changes.

Check TSBs
Refer to all technical service bulletins which pertain to the transaxle concern and follow the procedure as outlined.

Perform On-Board Diagnostics
After a road test, with the vehicle warm and before disturbing any connectors, perform the Quick Test 2.0 as outlined using Rotunda New Generation Star Tester 007-00500 or equivalent.