Diagnosis And Testing - Road Test - Chrysler 300M Service Manual

LH
42LE AUTOMATIC TRANSAXLE (Continued)
• Dynamic conditions (acceleration, deceleration,
upshift, cornering)
• Elements in use when condition occurs (what
gear is transaxle in during condition)
• Road and weather conditions
• Any other useful diagnostic information.
After noting all conditions, check the easily acces-
sible variables:
• Fluid level and condition
• Shift linkage adjustment
• Diagnostic trouble code inspection
Then perform a road test to determine if the prob-
lem has been corrected or that more diagnosis is nec-
essary. If the problem exists after the preliminary
tests and corrections are completed, hydraulic pres-
sure checks should be performed.

DIAGNOSIS AND TESTING - ROAD TEST

Prior to performing a road test, verify that the
fluid level, fluid condition, and linkage adjustment
have been approved.
ELEMENTS IN USE AT EACH POSITION OF SELECTOR LEVER
Shift Lever
Position
Underdrive
P - PARK
R - REVERSE
N - NEUTRAL
OD -
OVERDRIVE
First
Second
Direct
Overdrive
D - DRIVE*
First
Second
Direct
L - LOW*
First
Second
Direct
* Vehicle upshift and downshift speeds are increased when in these selector positions.
The process of elimination can be used to detect
any unit which slips and to confirm proper operation
of good units. Road test analysis can diagnose slip-
ping units, but the cause of the malfunction cannot
INPUT CLUTCHES
Overdrive
X
X
X X
X
X
X
X X
X
X
X X
During the road test, the transaxle should be oper-
ated in each position to check for slipping and any
variation in shifting.
If the vehicle operates properly at highway speeds,
but has poor acceleration, the converter stator over-
running clutch may be slipping. If acceleration is nor-
mal, but high throttle opening is needed to maintain
highway speeds, the converter stator clutch may
have seized. Both of these stator defects require
replacement of the torque converter and thorough
transaxle cleaning.
Slipping clutches can be isolated by comparing the
"Elements in Use" chart with clutch operation
encountered on a road test. This chart identifies
which clutches are applied at each position of the
selector lever.
A slipping clutch may also set a DTC and can be
determined by operating the transaxle in all selector
positions.
Reverse
X
be determined. Practically any condition can be
caused by leaking hydraulic circuits or sticking
valves.
TRANSAXLE 21 - 5
HOLDING CLUTCHES
2/4 Low/Reverse
X
X
X
X
X
X
X
X
X
X