Dodge 2004 Neon SRT4, Руководство по диагностике

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3rd, and 4th, the SSV will be in the upshifted
position and directs the fluid into the torque con-
verter clutch (TCC).
When doing PEMCC or FEMCC, the LR pres-
sure switch should indicate no pressure if the SSV
is in the TCC position. If the LR pressure switch
indicates pressure while in PEMCC or FEMCC,
EMCC operation is aborted and inhibited to avoid
inadvertent application of the LR clutch. Partial
EMCC will be attempted if the LR pressure switch
does not indicate pressure. A second detection of
LR pressure results in setting the code.
Transmission Effects: At speeds above 72 Km/h
(45 MPH), EMCC is inhibited. Once speed falls
below 72 Km/h (45 MPH), the transmission will go
into Limp-in mode and the MIL will illuminate
after 5 minutes of substituted operation.
Possible causes:
> Valve body - Solenoid valve stuck in LR position
> Intermittent short to ground or open circuit in
LR Pressure Switch Sense circuit (with code 24
only)
> Solenoid/Pressure Switch (with code P0841(24)
only)
> PCM (with code P0841(24) only)
Name of code: P0736(50) - Gear Ratio Error in
Reverse
P0731(51) - Gear Ratio Error in 1st
P0732(52) - Gear Ratio Error in 2nd
P0733(53) - Gear Ratio Error in 3rd
P0734(54) - Gear Ratio Error in 4th
P0715(56) - Input Speed Sensor Error
P0720(57) - Output Speed Sensor Error
P1794(58) - Speed Sensor Ground Error
When monitored: The transmission gear ratio is
monitored continuously while the transmission is
in gear.
Set condition: This code is set if the gear ratio is
not correct for a period of time.
– Codes 50 through 54 sets if the ratio of the
input RPM (Nt) to the output RPM (No) does
not match the given gear ratio.
– Code 56 sets if there is an excessive change in
input RPM in any gear
– Code 57 sets if there is an excessive change in
output RPM in any gear
– Code 58 sets after a PCM reset in neutral and
Nt/No equals a ratio of input to output of 2.50
A hard code sets within 3 seconds, an intermit-
tent code sets within 15 seconds.
Theory of operation: The transmission system
uses two speed sensors, one to measure input RPM
and one to measure output RPM. These inputs are
essential for proper transmission operation. There-
fore, the integrity of this data is verified through
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
operation will resume. If the gear ratio be-
comes intermittent and recovers three times
in a given key start, the current gear will be
maintained and EMCC inhibited. Then the
transmission 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-
mission will go to 2nd gear. If this happens
and the gear ratio problem goes away, normal
operation 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
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GENERAL INFORMATION