Diagnosis; Diagnostic Tests - SSANGYONG Rexton Y200 Manual

5D2-24 TRANSFER CASE - TOD
While the TOD is active it periodically monitors its inputs
and outputs. If a fault is detected the "4WD CHECK"
lamp is illuminated and a fault code is stored in the
TOD memory.
When requested, fault codes are downloaded to a
diagnostic connector (K-line) serial communications
using SCAN-100.

DIAGNOSTIC TESTS

TOD Internal Function
When the Ignition is turned on the TOD tests its ROM
and RAM. If there is a fault, the TOD immediately resets
itself and re-tests the ROM and RAM. If the fault
persists the TOD continues to reset and re-test until
the fault is corrected or the ignition is turned off. All
TOD functions are inhibited until the fault is corrected.
The 4WD CHECK lamp is not illuminated if there is a
ROM or RAM fault.
If the ROM/RAM passes the EEPROM memory is
tested. If there is a fault the 4WD CHECK lamp is
illuminated and the TOD continues to operate using
the default calibration data stored in ROM. Fault codes
are not stored when there is an EEPROM fault.
An EEPROM fault can only be cleared by cycling
ignition off-on.
Shift Motor Assembly Test
If the TOD detects a shift motor or position encoder
fault continuously for one second the "4WD CHECK"
lamp is turned on and the appropriate fault code is
stored in memory.
1. A shift motor fault when the motor is off is defined
as follows:
•
Motor H-L shorted to Ground
•
Motor L-H shorted to Ground
•
Motor open circuit
2. A shift motor fault when the motor is energized is
defined as follows:
•
Motor H-L shorted to Ground
•
Motor L-H shorted to Ground
•
Motor H-L shorted to Motor L-H
•
Motor open circuit
3. A position encoder fault is defined as follows:
•
Any position code which does not correspond
to the valid 9 codes.
•
A short to ground on any of the encoder lines.
4. If no shifts are in progress when a failure occurs
the TOD will not respond to any shift commands.

DIAGNOSIS

5. If a shift command has been received, but not
acted upon when a failure occurs the TOD will
cancel the command and not respond to any
subsequent shift commands.
6. If a shift command is in progress when an invalid
position code is confirmed it will be halted and
the TOD will turn the motor toward the high
position. Afterwards the TOD will not respond to
any shift commands.
7. If the shift motor/position encoder assembly
failure (other than a motor failure which occurs
when the motor is energized) recovers
continuously for one second the TOD will function
normally. The "4WD CHECK" lamp is turned off
but the fault code will remain in memory.
8. A motor failure (i.e. open or short circuit) which
occurs when the motor is energized can only be
cleared by cycling the ignition off-on.
Front Speed Sensor Test
If a Front Speed Sensor fault is detected continuously
for 0.5 second the 4WD CHECK lamp is illuminated.
The TOD then responds as follows:
1. If the system is in High Range the TOD uses the
Rear Speed Sensor to determine the EMC Touch
Off level and wheel slip control is suspended.
2. If the system is in Low Range, the EMC Duty Cycle
is set to maximum (independent of vehicle speed)
until the system is shifted out of 4L.
3. All Electric Shift activity is halted until the Ignition
is cycled. If a shift is in progress it will be
completed.
If the Front Speed Sensor recovers continuously for
O.5 second the TOD will function normally. The 4WD
CHECK lamp is turned off but the fault code will remain
in memory.
Rear Speed Sensor Test
If a Rear Speed Sensor fault is detected continuously
for 0.5 second the 4WD CHECK lamp is illuminated.
The TOD then responds as follows:
1. If the system is in High Range the TOD uses the
Front Speed Sensor to determine the EMC Touch
Off level and wheel slip control is suspended.
2. If the system is in Low Range, the EMC Duty Cycle
is set to maximum (independent of vehicle speed)
until the system is shifted out of 4L.
3. All Electric Shift activity is halted until the Ignition
is cycled. If a shift is in progress it will be
completed.
If the Rear Speed Sensor recovers continuously for
0.5 second the TOD will function normally. The "4WD
CHECK" lamp is turned off but the fault code will remain
in memory.
SSANGYONG Y200