Symptom Related Diagnostic Procedures
MECHANICAL/HYDRAULIC DIAGNOSIS CHECK TRANS INDICATOR CHARTPERFORM PRELIMINARY INSPECTION FIRST!
When the "CHECK TRANS" indicator is flashing, it indicates that a problem related to the transmission, the Powertrain Control Module (PCM), or the vehicle harness has occurred. The system is now operating in a "BACKUP MODE" where the risk of further damaging the transmission has been reduced. The vehicle may be shifted manually. If the initial problem is intermittent or seldom, switching the engine OFF/ON might allow normal operation again until the problem reoccurs.
MECHANICAL/HYDRAULIC DIAGNOSIS SYMPTOMS INDEX
PERFORM PRELIMINARY INSPECTION FIRST!
NOTE: Numbers with parenthesis on the following charts refer to Diagrams / Exploded Views.
CHART 1: NO ENGINE START IN NEUTRAL OR PARK
CHART 2: NO FORWARD GEARS IN ANY RANGE/NO REVERSE
CHART 3: NO ENGINE BRAKE IN ANY RANGE
CHART 4: POOR SHIFTING IN ALL GEARS (ALL HARSH OR ALL SOFT)
CHART 5A: DELAYS IN DRIVE AND REVERSE
NOTE: A short delay (less than 3 seconds) when first engaging drive or reverse after allowing vehicle to sit overnight is normal.
CHART 5B: DELAYS IN REVERSE ONLY
CHART 6: DIAGNOSTIC TROUBLE CODE (DTC) P0730
CHART 7: HARSH 1-2 SHIFT
CHART 8: HARSH 3-4 SHIFT
CHART 9A: 3-2 DOWNSHIFT COMPLAINT
CHART 9B: HARSH SHIFT WHEN SHIFTING INTO "D" OR ACCELERATING FROM STOP
CHART 9C: COASTDOWN HARSH SHIFT OR CLUNK AT 3-2 DOWNSHIFT
CHART 10: INTERMITTENT 4TH TO 2ND GEAR DOWNSHIFT AT STEADY SPEED
CHART 11: ENGINE FLARE AT SHIFTING DURING TURNING ONLY (USUALLY WITH WARM ENGINE)
CHART 12: ENGINE FLARE DURING 1-2 OR 2-3 SHIFT
CHART 13: SHUDDER ONLY DURING TORQUE CONVERTER CLUTCH (TCC) APPLYING
CHART 14: POSSIBLE CAUSES OF TRANSMISSION NOISE
CAUTION: Before checking transmission for what is believed to be transmission noise, ensure presence and positioning of insulating plugs, pads etc. Also make sure that noise does not come from other drivetrain components.
CHART 15A: POSSIBLE CAUSES OF LOW LINE PRESSURE
CHART 15B: POSSIBLE CAUSES OF HIGH LINE PRESSURE
NOTE: If transmission is operating in backup mode, high line pressure will be present.
CHART 16: POSSIBLE CAUSES OF TRANSMISSION FLUID LEAKS
Before attempting to correct an oil leak, the actual source of the leak must be determined. In many cases, the source of the leak may be difficult to determine due to "wind flow" around the engine and transmission. The suspected area should be wiped clean before inspecting for the source of the leak. Oil leaks around the engine and transmission are generally carried toward the rear of the vehicle by the air stream. In determining the source of an leak, the following two checks should be made:
1. With the engine running, check for external line pressure leaks.
2. With the engine off, check for oil leaks due to the raised oil level caused by drainback of converter oil into the transmission.
POSSIBLE CAUSES OF FLUID LEAKS DUE TO SEALING MALFUNCTION