Mitsubishi Galant. Manual — part 409

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-103

STEP 16. Check connectors C-17 at intermediate
connector and C-77 at junction block for damage.
Q: Are the connectors in good condition?

YES : Go to Step 17.
NO : Repair or replace it. Refer to GROUP 00E, Harness

Connector Inspection

P.00E-2

.

STEP 17. Check harness for damage between input shaft
speed sensor harness side connector B-40 terminal 2 and
PCM connector C-42 terminal 103.
Q: Is the harness wire in good condition?

YES : Go to Step 18.
NO : Repair it.

AC004308AB

CONNECTOR: C-17

AC004307

CONNECTOR: C-77

JUNCTION BLOCK
(FRONT VIEW)

C-77

AC

AC001835

CONNECTOR: B-40

AF

AC004197

PCM

AF

CONNECTOR: C-42

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-104

STEP 18. Check harness for damage between input shaft
speed sensor harness side connector B-40 terminal 1 and
PCM connector C-40 terminal 57.
Q: Is the harness wire in good condition?

YES : Go to Step 19.
NO : Repair it.

STEP 19. Check harness for damage between input shaft
speed sensor harness side connector B-40 terminal 3 and
junction block connector C-77 terminal 12.
Q: Is the harness wire in good condition?

YES : Go to Step 20.
NO : Repair it.

AC001835

CONNECTOR: B-40

AF

AC004197

PCM

AD

CONNECTOR: C-40

AC001835

CONNECTOR: B-40

AF

AC004307

CONNECTOR: C-77

JUNCTION BLOCK
(FRONT VIEW)

C-77

AC

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-105

STEP 20. Replace the underdrive clutch retainer.
(1) Replace the underdrive clutch retainer. Refer to GROUP

23B, Underdrive Clutch and Input Shaft

P.23B-51

.

(2) Carry out a test drive.
(3) Read in the diagnostic trouble code.

Q: Is the A/T diagnostic trouble code number "22" output?

YES : The A/T diagnostic trouble code may have set due to

external radio frequency (RFI), possibly caused by
cellular phone activity, after market components
installed on the vehicle, etc.

NO : The inspection is complete.

DTC 23: Output Shaft Speed Sensor System

AC001836AB

AC004614

Output Shaft Speed Sensor System Circuit

AB

AUTOMATIC TRANSAXLE DIAGNOSIS

TSB Revision

AUTOMATIC TRANSAXLE

23A-106

CIRCUIT OPERATION

•

A coil built into the output shaft speed sensor
generates 0

⇔

5 volts pulse signal at both ends

of this coil when the output shaft rotates. The
pulse signal frequency increases with a rise in
output shaft speed.

•

Both ends of the coil are connected to the PCM
(terminals 57 and 104) via the output shaft speed
sensor connector (terminals 1 and 2).

•

The PCM detects the output shaft speed by the
signal input to terminal 104.

•

The output shaft speed sensor generates the
pulse signal as the teeth of the transfer drive gear
pass the magnetic tip of the sensor.

DTC SET CONDITIONS
If the output from the output shaft speed sensor is
continuously 50 percent lower than the vehicle speed
for one second or more while driving in 3rd or 4th
gear at a speed of 30 km/h (19 mph) or more, it is
judged to be an open circuit or short-circuit in the
output shaft speed sensor and diagnostic trouble
code number "23" is output. If diagnostic trouble
code number "23" is output four times, the
transmission is locked into 3rd gear or 2nd gear as a
fail-safe measure.

TROUBLESHOOTING HINTS (The most likely

causes for this code to be set:)

•

Malfunction of the output shaft speed sensor

•

Malfunction of the transfer drive gear or driven
gear

•

Damaged harness, connector

•

Malfunction of the PCM

DIAGNOSIS

Required Special Tool:
MB991502: Scan Tool (MUT-II)

AC001837AG

CONNECTOR: B-37

AC004308AB

CONNECTOR: C-17

AC004197

PCM

C-40

C-42

CONNECTORS: C-40, C-42

AE

AC004307

CONNECTORS: C-73, C-77

C-73

JUNCTION BLOCK
(FRONT VIEW)

C-77

AB