Mitsubishi Space Star. Manual - part 112

AUTOMATIC TRANSMISSION –

Troubleshooting <A/T>

23-15

Code No. 26 Stop lamp switch system

Probable cause

If the stop lamp switch is on for 5 minutes or more while driving, it is judged that
there is a short circuit in the stop lamp switch and diagnosis code No. 26 is output.

Malfunction of the stop lamp switch

Malfunction of connector

Malfunction of the engine-A/T-ECU

Stop lamp switch check (Refer to GROUP 35 – On-vehicle Service.)

Replace

Check the following connectors: B-39, B-61X, B-19, B-87

Repair

Harness check

Between stop lamp switch and engine-A/T-ECU

Repair

Check the trouble symptoms.

Replace the engine-A/T-ECU.

Code No. 31 Low and reverse solenoid valve system

Probable cause

Code No. 32 Underdrive solenoid valve system

Code No. 33 Second solenoid valve system

Code No. 34 Overdrive solenoid valve system

If the resistance value for a solenoid valve is too large or too small, it is judged
that there is a short-circuit or an open circuit in the solenoid valve and the respective
diagnosis code is output. The transmission is locked into 3rd gear as a fail-safe
measure, and the N range lamp flashes at a frequency of 1 Hz.

Malfunction of solenoid valve

Malfunction of connector

Malfunction of the engine-A/T-ECU

Solenoid valve check (Refer to P.23-49.)

Replace

Check the following connectors: A-100, B-87

Repair

Harness check

Between solenoid valve and engine-A/T-ECU

Between solenoid valve and A/T control relay

Repair

Replace the solenoid valve.

Check the trouble symptoms.

Replace the engine-A/T-ECU.

AUTOMATIC TRANSMISSION –

Troubleshooting <A/T>

23-16

Code No. 36, 52 Damper clutch control solenoid valve
system

Probable cause

If the resistance value for the damper clutch control solenoid valve is too large
or too small, it is judged that there is a short-circuit or an open circuit in the damper
clutch control solenoid valve and diagnosis code No. 36 is output. If the drive duty
rate for the damper clutch control solenoid valve is 100 % for a continuous period
of 4 seconds or more, it is judged that there is an abnormality in the damper clutch
control system and diagnosis code No. 52 is output. When diagnosis code No.
36 is output, the transmission is locked into 3rd gear as a fail-safe measure, and
the N range lamp flashes at a frequency of 1 Hz.

Malfunction of the damper clutch control solenoid
valve

Malfunction of connector

Malfunction of the engine-A/T-ECU

Damper clutch control solenoid valve check (Refer to P.23-49.)

Replace

Check the following connectors: B-83, A-100, B-87

Repair

Harness check

Between damper clutch control solenoid valve and
engine-A/T-ECU

Between damper clutch control solenoid valve and A/T control
relay

Repair

Replace the damper clutch control solenoid valve.

Check the trouble symptoms.

Replace the engine-A/T-ECU.

AUTOMATIC TRANSMISSION –

Troubleshooting <A/T>

23-17

Code No. 41 1st gear ratio does not meet the specification

Probable cause

Code No. 42 2nd gear ratio does not meet the specification

Code No. 43 3rd gear ratio does not meet the specification

Code No. 44 4th gear ratio does not meet the specification

Code No. 46 Reverse gear ratio does not meet the
specification

If the output from the output shaft speed sensor multiplied by each gear ratio is
not the same as the output from the input shaft speed sensor after shifting to each
gear has been completed, each diagnosis code is output. If each diagnosis code
is output four times, the transmission is locked into 3rd gear as a fail-safe measure,
and the N range lamp flashes at a frequency of 1 Hz.

Malfunction of the input shaft speed sensor

Malfunction of the output shaft speed sensor

Malfunction of the underdrive clutch retainer

Malfunction of the transfer drive gear or driven gear

Malfunction of the low and reverse brake system (for
code No.41, 46)

Malfunction of the underdrive clutch system (for code
No.41 42, 43)

Malfunction of the second brake system (for code
No.42, 44)

Malfunction of the overdrive clutch system (for code
No.43, 44)

Malfunction of the reverse clutch system (for code
No.46)

Noise generated

: Refer to the Transmission Workshop Manual.

MUT-

Self-Diag code

Is the diagnosis code No. 22 output?

YES

Code No. 22 Input shaft speed sensor system check
(Refer to P.23-13.)

MUT-

Self-Diag code

Is the diagnosis code No. 23 output?

YES

Code No. 23 Output shaft speed sensor system check
(Refer to P.23-14.)

Measure output waveform from the input shaft speed sensor. (using
an oscilloscope)

Connect the connector B-87, B-86 and measure voltage
between 81 and 103 at the engine-A/T-ECU.

Engine: 2,000 r/min (approx. 50 km/h)

Selector lever position: 3
(Voltage)
OK: A waveform such as the one shown on P.23-38 (Inspec-

tion Procedure Using an Oscilloscope) is output (flashing
between 0

←→

5V) and there is no noise appearing

in the waveform.

Replace the input shaft speed sensor.

Check the trouble symptoms.

A/T overhaul

Replace the underdrive clutch retainer.

Check the trouble symptoms.

Eliminate the cause of the noise.

Measure output waveform from the output shaft speed sensor.
(using an oscilloscope)

Connect the connector B-87, B-86 and measure voltage
between 81 and 104 at the engine-A/T-ECU.

Engine: 2,000 r/min (approx. 50 km/h)

Selector lever position: 3
(Voltage)
OK: A waveform such as the one shown on P.23-45 (Inspec-

tion Procedure Using an Oscilloscope) is output (flashing
between 0

←→

5V) and there is no noise appearing

in the waveform.

Replace the output shaft speed sensor.

Check the trouble symptoms.

A/T overhaul

Replace the transfer drive gear and driven gear.

Check the trouble symptoms.

Eliminate the cause of the noise.

Low and reverse brake system check (for code No.41, 46)

Underdrive clutch system check (for code No.41 42, 43)

Second brake system check (for code No.42, 44)

Overdrive clutch system check (for code No.43, 44)

Reverse clutch system check (for code No.46)

AUTOMATIC TRANSMISSION –

Troubleshooting <A/T>

AUTOMATIC TRANSMISSION –

Troubleshooting <A/T>

23-18

Code No. 51 Abnormal communication with engine-ECU

Probable cause

If normal communication is not possible for a continuous period of 1 second or
more when the ignition switch is at the ON position, the battery voltage is 10 V
or more and the engine speed is 450 r/min or more, diagnosis code No. 51 is output.
Diagnosis code No. 51 is also output if the data being received is abnormal for
a continuous period of 4 seconds under the same conditions.

Malfunction of connector

Malfunction of the engine-A/T-ECU

Replace the engine-A/T-ECU.

Code No. 54 A/T control relay system

Probable cause

If the A/T control relay voltage is less than 7 V after the ignition switch has been
turned ON, it is judged that there is an open circuit or a short

circuit in the A/T

control relay earth and diagnosis code No. 54 is output.
Then the transmission is locked into 3rd gear as a fail

safe measure, and the N

range lamp flashes at a frequency of 1 Hz.

Malfunction of the A/T control relay

Malfunction of connector

Malfunction of the engine-A/T-ECU

Check the A/T control relay. (Refer to P.23-49.)

Replace

Check the following connectors: A-23, B-83, B-86, B-85

Repair

Harness check

Between control relay and body earth

Between control relay and battery

Between control relay and engine-A/T-ECU

Repair

Check the trouble symptoms.

Replace the engine-A/T-ECU.

Code No. 56 N range lamp system

Probable cause

If the N range signal is off after an N range lamp illumination instruction (ON instruction)
has been given, it is judged that there is a short-circuit in the N range lamp earth
and diagnosis code No. 56 is output.

Malfunction of the N range lamp bulb

Malfunction of connector

Malfunction of the engine-A/T-ECU

Check the N range lamp bulb

Replace

Check the following connectors: A-99, B-87

Repair

Harness check

Between N range lamp bulb and engine-A/T-ECU

Repair

Check the trouble symptoms.

Replace the engine-A/T-ECU.

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