Automatic Transmission - 6-Speed PowerShift Transmission - MPS6/6DCT450 - Diagnostic Strategy

Diagnosis and Testing General Equipment Ultraviolet fluid leak detection equipment Inspection and Verification Verify the customer concern. Visually inspect for obvious signs of mechanical damage. Visual Inspection Chart Mechanical Oil leaks. Visibly damaged or worn components. Loose or missing nuts or bolts. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step. If the cause is not evident, verify the symptom and REFER to the Symptom Chart. The following checks should be carried out before repairing or installing a new transaxle. The inspection and verification of manual transaxle concerns can be considered in three main areas. Gear shifting concerns Check the operation of the clutch: Lay a block of wood approximately 25 mm thick under the clutch pedal and depress the clutch pedal as far as the stop. If first or second gear can be selected with the engine running and the parking brake applied, without any concerns, the clutch is OK. If the gear(s) cannot be selected, REFER to the Symptom Chart. Transaxle noise concerns Check the engine and transaxle support for insufficient gap between the transaxle and the body. Road test the vehicle. REFER to: Road/Roller Testing (100-00 General Information, Description and Operation). If a noise occurs in various gears at the same engine speed, check if the noise also occurs in the neutral position. If it does, the noise is not caused by the transaxle. REFER to the Symptom Chart. Oil leakage concerns Check the transaxle fluid level. If necessary, drain off any excess fluid. Clean the transaxle and the adjacent areas carefully and road test the vehicle. REFER to: Road/Roller Testing (100-00 General Information, Description and Operation). Using suitable ultraviolet fluid leak detection equipment, locate the leak and check whether the leaking fluid is transaxle fluid, brake fluid (from the hydraulically operated clutch) or engine oil. REFER to the Symptom Chart. Symptom Chart Symptom Possible Sources Action Clutch slippage * Clutch master cylinder. * Clutch slave cylinder. * Clutch pressure plate. * Clutch disc. * Engine or transaxle housing oil or fluid leak(s). * GO to Pinpoint Test A. Clutch chatter or shudder * Engine and transaxle mounts. * REFER to: Noise, Vibration and Harshness (NVH) (100-04 Noise, Vibration and Harshness, Diagnosis and Testing). * Clutch pressure plate. * Clutch disc. * Flywheel. * GO to Pinpoint Test B. Clutch drag * Insufficient brake fluid. * FILL the brake master cylinder reservoir to the MAX mark. INSPECT the brake and clutch hydraulic systems for leaks. REPAIR as necessary. * Air in the clutch hydraulic system. * BLEED the system. REFER to: (308-00 Manual Transmission and Clutch - General Information - 5-Speed Manual Transmission - B5A/5-Speed Manual Transmission - B5/IB5) Clutch System Bleeding (General Procedures), Clutch System Bleeding (General Procedures). * Clutch pedal free travel. * Clutch pressure plate. * Clutch disc. * Crankshaft end play. * GO to Pinpoint Test C. Clutch pedal pulsation * Clutch pressure plate. * Clutch disc. * INSTALL a new clutch disc and pressure plate. REFER to: (308-01 Clutch - 5-Speed Manual Transmission - B5/IB5) Clutch Disc and Pressure Plate (Removal and Installation), Clutch Disc and Pressure Plate (Removal and Installation). * Crankshaft end play. * CHECK the crankshaft end play. Hard shifting * Clutch drag. * GO to Pinpoint Test C. * Gearshift cable adjustment * CHECK the gearshift cable adjustment. REFER to: (308-00 Manual Transmission and Clutch - General Information - 5-Speed Manual Transmission - B5A/5-Speed Manual Transmission - B5/IB5) Gearshift Cable Adjustment - 5-Speed Manual Transmission - B5/IB5 (General Procedures), Gearshift Cable Adjustment - 5-Speed Manual Transmission - B5/IB5 (General Procedures). * External controls. * CHECK the external controls for wear or damage. INSTALL new components as necessary. * Gear wheels. * DISASSEMBLE the transaxle. REFER to: (308-03 Manual Transmission - 5-Speed Manual Transmission - B5/IB5) Transmission (Disassembly), Transmission (Disassembly). INSTALL new components as necessary. * Selector mechanism. * DISASSEMBLE the transaxle. REFER to: (308-03 Manual Transmission - 5-Speed Manual Transmission - B5/IB5) Transmission (Disassembly), Transmission (Disassembly). INSTALL new components as necessary. * Synchronizer(s). * DISASSEMBLE the transaxle. REFER to: (308-03 Manual Transmission - 5-Speed Manual Transmission - B5/IB5) Transmission (Disassembly), Transmission (Disassembly). INSTALL new components as necessary. Excessive noise * Engine vibrations inadequately damped. * REFER to: Noise, Vibration and Harshness (NVH) (100-04 Noise, Vibration and Harshness, Diagnosis and Testing). * Transaxle fluid level low. * CHECK the transaxle for leaks. TOP UP the transmission fluid. * Engine or transaxle is in contact with the chassis or body. * Check the powertrain/drivetrain mount alignment. * Engine and transaxle out of alignment. * Check the powertrain/drivetrain mount alignment. * External controls. * CHECK the external controls for wear or damage. INSTALL new components as necessary. * Gear wheels and bearings. * DISASSEMBLE the transaxle. REFER to: (308-03 Manual Transmission - 5-Speed Manual Transmission - B5/IB5) Transmission (Disassembly), Transmission (Disassembly). INSTALL new components as necessary. * Clutch pedal. * Clutch release bearing. * GO to Pinpoint Test D. Fluid leakage * Clutch master cylinder. * Clutch slave cylinder. * Clutch hydraulic lines. * INSPECT the brake and clutch hydraulic systems for leaks. REPAIR as necessary. * Halfshaft seal. * INSTALL a new halfshaft seal. REFER to: (308-03 Manual Transmission - 5-Speed Manual Transmission - B5/IB5) Halfshaft Seal LH (Removal and Installation), Halfshaft Seal RH (Removal and Installation), Halfshaft Seal LH (Removal and Installation), Halfshaft Seal RH (Removal and Installation). * Fluid leak between the transaxle housing sections. * DISASSEMBLE the transaxle and clean the mating faces. CHECK the mating faces for damage. SEAL the transaxle with sealant. REFER to: (308-03 Manual Transmission - 5-Speed Manual Transmission - B5/IB5) Transmission (Disassembly), Transmission (Disassembly). PINPOINT TEST A : CLUTCH SLIPPAGE TEST CONDITIONS DETAILS/RESULTS/ACTIONS A1: TEST CLUTCH SLIPPAGE 1 Lock the wheels and apply the parking brake. 2 Start the engine and engage fourth gear. 3 Run the engine at approximately 2000 rpm. 4 Release the clutch pedal slowly. Does the engine stall when the clutch pedal is fully released? Yes Clutch OK. No GO to A2. A2: CHECK THE CLUTCH PEDAL OPERATION 1 Depress clutch pedal and allow it to return. Does the pedal return to the initial position? Yes GO to A3. No GO to A4. A3: CHECK THE CLUTCH DISC AND PRESSURE PLATE 1 Remove the clutch disc and pressure plate. REFER to: (308-01 Clutch - 5-Speed Manual Transmission - B5/IB5) Clutch Disc and Pressure Plate (Removal and Installation), Clutch Disc and Pressure Plate (Removal and Installation). Is the clutch disc or pressure plate contaminated with oil or hydraulic fluid? Yes CHECK the engine and transaxle for leaks. INSTALL new components as necessary. TEST the system for normal operation. No INSTALL a new clutch disc and pressure plate. REFER to: (308-01 Clutch - 5-Speed Manual Transmission - B5/IB5) Clutch Disc and Pressure Plate (Removal and Installation), Clutch Disc and Pressure Plate (Removal and Installation). TEST the system for normal operation. A4: CHECK THE CLUTCH HYDRAULIC SYSTEM 1 Release the clutch slave cylinder bleed nipple. Does the pedal return to the initial position? Yes INSTALL a new clutch slave cylinder. REFER to: (308-02 Clutch Controls - 5-Speed Manual Transmission - B5/IB5/6-Speed Manual Transmission - B6) Clutch Slave Cylinder (Removal and Installation), Clutch Slave Cylinder (Removal and Installation). TEST the system for normal operation. No INSTALL a new clutch master cylinder. REFER to: (308-02 Clutch Controls - 5-Speed Manual Transmission - B5/IB5/6-Speed Manual Transmission - B6) Clutch Master Cylinder - Vehicles Built Up To: 04-10-2012 (Removal and Installation), Clutch Master Cylinder - Vehicles Built Up To: 04-10-2012 (Removal and Installation). TEST the system for normal operation. PINPOINT TEST B : CLUTCH CHATTER OR SHUDDER TEST CONDITIONS DETAILS/RESULTS/ACTIONS B1: TEST FOR CLUTCH SHUDDER 1 Start the engine. 2 Engage the clutch and select fourth gear. 3 Run the engine at approximately 2000 rpm. 4 Release the clutch pedal slowly. Does the clutch take up the drive smoothly? Yes Clutch is OK. No GO to B2. B2: CHECK THE CLUTCH DISC AND PRESSURE PLATE FOR OIL OR HYDRAULIC FLUID CONTAMINATION 1 Remove the clutch disc and pressure plate. REFER to: (308-01 Clutch - 5-Speed Manual Transmission - B5/IB5) Clutch Disc and Pressure Plate (Removal and Installation), Clutch Disc and Pressure Plate (Removal and Installation). Is the clutch disc and pressure plate contaminated with oil or hydraulic fluid? Yes CHECK the engine and transaxle for leaks. INSTALL new components as necessary. TEST the system for normal operation. No GO to B3. B3: CHECK THE CLUTCH DISC AND PRESSURE PLATE 1 Visually check the clutch disc and pressure plate. Is the clutch disc and pressure plate worn or damaged? Yes INSTALL a new clutch disc and pressure plate. REFER to: (308-01 Clutch - 5-Speed Manual Transmission - B5/IB5) Clutch Disc and Pressure Plate (Removal and Installation), Clutch Disc and Pressure Plate (Removal and Installation). TEST the system for normal operation. No INSPECT the flywheel clutch surface. TEST the system for normal operation. PINPOINT TEST C : CLUTCH DRAG TEST CONDITIONS DETAILS/RESULTS/ACTIONS C1: CHECK THE OPERATION OF THE CLUTCH PEDAL 1 Bleed the clutch system. REFER to: (308-00 Manual Transmission and Clutch - General Information - 5-Speed Manual Transmission - B5A/5-Speed Manual Transmission - B5/IB5) Clutch System Bleeding (General Procedures), Clutch System Bleeding (General Procedures). Does the clutch properly disengage after bleeding? Yes Clutch system is OK. No GO to C2. C2: CHECK THE CLUTCH DISC AND PRESSURE PLATE FOR OIL OR HYDRAULIC FLUID CONTAMINATION 1 Remove the clutch disc and pressure plate. REFER to: (308-01 Clutch - 5-Speed Manual Transmission - B5/IB5) Clutch Disc and Pressure Plate (Removal and Installation), Clutch Disc and Pressure Plate (Removal and Installation). Is the clutch disc and pressure plate contaminated with oil or hydraulic fluid? Yes CHECK the engine and transaxle for leaks. INSTALL new components as necessary. TEST the system for normal operation. No GO to C3. C3: CHECK THE CLUTCH DISC AND PRESSURE PLATE 1 Visually check the clutch disc and pressure plate. Is the clutch disc and pressure plate worn or damaged? Yes INSTALL a new clutch disc and pressure plate. REFER to: (308-01 Clutch - 5-Speed Manual Transmission - B5/IB5) Clutch Disc and Pressure Plate (Removal and Installation), Clutch Disc and Pressure Plate (Removal and Installation). TEST the system for normal operation. No GO to C4. C4: CHECK THE INPUT SHAFT SPLINES 1 Check that the clutch disc slides freely on the input shaft splines. Does the clutch disc stick on the input shaft? Yes CHECK the clutch disc and input shaft splines for damage. INSTALL new components as necessary. TEST the system for normal operation. No MEASURE the crankshaft end play. PINPOINT TEST D : EXCESSIVE NOISE TEST CONDITIONS DETAILS/RESULTS/ACTIONS D1: STATIC CHECK 1 Depress and release the clutch pedal. Is the noise apparent when the clutch is operated? Yes LUBRICATE the clutch and brake pedal shaft. TEST the system for normal operation. No GO to D2. D2: DYNAMIC CHECK 1 Start the engine. 2 Depress the clutch pedal. Is the noise apparent when the clutch pedal is depressed? Yes REFER to: Engine (303-00 Engine System - General Information, Diagnosis and Testing). No INSTALL a new clutch slave cylinder and release bearing assembly. REFER to: Clutch Slave Cylinder (308-02 Clutch Controls - 5-Speed Manual Transmission - B5/IB5/6-Speed Manual Transmission - B6, Removal and Installation), Clutch Slave Cylinder (308-02 Clutch Controls - 5-Speed Manual Transmission - B5/IB5/6-Speed Manual Transmission - B6, Removal and Installation), Clutch Disc and Pressure Plate (308-01 Clutch - 5-Speed Manual Transmission - B5/IB5, Removal and Installation), Clutch Disc and Pressure Plate (308-01 Clutch - 5-Speed Manual Transmission - B5/IB5, Removal and Installation). TEST the system for normal operation.