Chrysler 300M 2002 Service Manual page 2812

the following checks:
1) When in gear, if the gear ratio does not compare
to a known gear ratio, the corresponding in-gear
trouble code is set (codes 50 through 54).
2) An excessive change in input or output speeds
indicating signal intermittent will result in codes
56 and/or 57 being set.
3) After a PCM reset in neutral, observing erratic
output and input speed sensor signals indicates a
loss of the common speed sensors ground. This sets
a code 58.
Transmission Effects: The transmission will not
go into Limp-in mode until three gear ratio error
events occur in a given key start also the MIL will
illuminate after 5 minutes of substituted opera-
tion. This allows for intermittent problems to cor-
rect themselves without opening the relay. How-
ever, if a gear ratio error develops, a code is always
set, but if the condition corrects itself the transmis-
sion will continue without requiring the ignition
key to be cycled on and off. Many different events
could occur given the range of failures possible for
codes 50 through 58. The following are a few
examples:
– Codes 51, 52, 53, 54, 56, and 57 at speeds
above 72 Km/h (45 MPH) - The appropriate
code is set, EMCC is aborted and current gear
is maintained. If while still traveling above 72
Km/h (45 MPH), the gear ratio becomes valid
again, EMCC will reengage and normal oper-
ation will resume. If the gear ratio becomes
intermittent and recovers three times in a
given key start, the current gear will be main-
tained and EMCC inhibited, then the trans-
mission will go into limp-in mode if throttle is
applied below 72 Km/h (45 MPH) or at 35
Km/h (22 MPH) with closed throttle.
– Codes 51, 52, 53, 54, 56, and 57 at speeds
between 35 and 72 Km/h (22 and 45 MPH) - If
one of these codes is set between 35 and 72
Km/h (22 and 45 MPH), the current gear will
be maintained until the gear ratio problem
corrects itself. If throttle is applied, the trans
will go to 2nd gear. If this happens and the
gear ratio problem goes away, normal opera-
tion will resume. If three gear ratio problems
are identified in a given key start, the current
gear will be frozen until throttle is applied.
The transmission will then go into Limp-in
mode with throttle applied at speeds between
35 and 72 Km/h (22 and 45 MPH).
– Codes 51, 52, 53, 54, 56, and 57 at speeds
below 35 Km/h (22 MPH) - If a gear ratio
problem is identified below 35 Km/h (22
MPH), the transmission will immediately
substitute second gear for the current gear. If
the gear ratio problem goes away, normal
GENERAL INFORMATION
operation will resume. If three gear ratio
problems are identified in a given key start,
the transmission will go into Limp-in mode.
Possible causes:
Code P0736(50) - Excludes geartrain failures
which should be obvious upon disassembly
> If code P0944(35) is also set, follow diagnostic
procedure for code P0944(35) first
> Valve body - #1 ball check or LR switch valve
sticking - may also set code P0731(51)
> Speed sensor or associated wiring - may also set
codes P0731(51), P0715(56), or P0720(57)
> Failed or slipping LR clutch - may also set code
P0731(51)
– LR seal leakage (Intermittent no drive or
reverse)
– Sticky LR accumulator seals (Intermittent no
drive or reverse)
> Failed reverse clutch (hard code)
– OD/Rev lip seal leakage
– Worn reaction shaft support seal rings
– Snap ring out of position
Code P0731(51) - Excludes geartrain failures
which should be obvious upon disassembly
> If code P0944(35) is also set, follow diagnostic
procedure for code P0944(35) first
> Valve body - #1 check ball or LR switch valve
sticking - may also set code P-0736(56) or have
no Reverse
> Speed sensor or associated wiring - may also set
codes P0736(50), P0715(56), or P0720(57)
> Failed or intermittent slipping UD clutch - may
also set P0732(52), or P0733(53)
– UD seal leakage (intermittent)
– Worn input clutch hub bushing (hard code at
heavy throttle)
– Sticky UD accumulator seals (intermittent)
– Worn reaction shaft support seal rings (hard
code at heavy throttle)
– Solenoid pack (UD pressure in 4th gear
> Failed or slipping LR clutch - may also set code
P0736(56) or have no Reverse
– LR seal leakage (Intermittent)
– Sticky LR accumulator seals (Intermittent)
Code P0732(52) - Excludes geartrain failures
which should be obvious upon disassembly
> If code P0944(35) is also set, follow diagnostic
procedure for code P0944(35)
> Failed or slipping 2/4 clutch - may also set code
P-0734(54)
– 2/4 seat leakage (intermittent)
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