Code No. 41 (1st), 42 (2nd), 43 (3rd), 44 (4th), 45 (5th) <5A/T>, 46 (reverse): Gear Incorrect Ratio

OPERATION

The engine-A/T-ECU detects the current gear/speed according to the output signals from the input and output shaft speed sensor.

DIAGNOSIS CODE SET CONDITIONS

If the output from the output shaft speed sensor multiplied by the gear ratio is not the same as the output from the input shaft speed sensor after completing of shifting, the corresponding diagnosis code is output.
If each diagnosis code is output 4 times, the transmission is fixed in 3rd as a fail-safe measure.

PROBABLE CAUSES

Malfunction of input shaft speed sensor

Malfunction of output shaft speed sensor

Damaged harness wires and connectors

Malfunction of the engine-A/T-ECU

Malfunction of solenoid valve

Malfunction of underdrive clutch retainer

Malfunction of valve body

Malfunction of transfer drive gear or driven gear <4A/T>

Malfunction of direct planetary carrier <5A/T>

Malfunction of low-reverse brake system (for diagnosis codes 41, 46)

Malfunction of underdrive clutch system (for diagnosis codes 41, 42, 43, 44 <5A/T>)

Malfunction of second brake system (for diagnosis codes 42, 44 <4A/T>, 45 <5A/T>)

Malfunction of overdrive clutch system (for diagnosis codes 43, 44, 45 <5A/T>)

Malfunction of reduction brake system <5A/T> (for diagnosis codes 41, 42, 43, 46)

Malfunction of direct clutch system <5A/T> (for diagnosis codes 44, 45)

Malfunction of reverse clutch system (for diagnosis code 46)

Malfunction of one-way clutch system (for diagnosis code 41)

DIAGNOSIS PROCEDURE

STEP 1. MUT-II/III diagnosis code

Either of diagnosis codes 41, 42, 43, 44, 45 <5A/T> or 46 is output, the input shaft speed sensor or output shaft speed sensor is defective.

Q: Are diagnosis codes 22 or 23 output?

YES <diagnosis code 22 is output>: Refer to diagnosis code 22: Input shaft speed sensor system

.
YES <diagnosis code 23 is output>: Refer to diagnosis code 23: Output shaft speed sensor system

.
NO: Go to Step 2

STEP 2. MUT-II/III diagnosis code

Either of diagnosis codes 41, 42, 43, 44, 45 <5A/T> or 46 is output, the corresponding solenoid valve is defective.

Q: Is either of diagnosis code 31, 32, 33, 34, 35 <5A/T> output?

YES <diagnosis code 31 is output>: Refer to diagnosis code: 31 Low-reverse solenoid valve system

.
YES <diagnosis code 32 is output>: Refer to diagnosis code 32: Underdrive solenoid valve system

.
YES <diagnosis code 33 is output>: Refer to diagnosis code 33: Second solenoid valve system

.
YES <diagnosis code 34 is output>: Refer to diagnosis code 34: Overdrive solenoid valve system

.
YES <diagnosis code 35 is output>: Refer to diagnosis code 35: Reduction solenoid valve system

.
NO: Go to Step 3

STEP 3. Hydraulic pressure test

Each hydraulic pressure of the elements below, which diagnosis codes indicate, should be within the standard value.

diagnosis code 41: Underdrive clutch, low-reverse brake, reduction brake <5A/T>

diagnosis code 42: Underdrive clutch, low-reverse brake, reduction brake <5A/T>

diagnosis code 43: Underdrive clutch, overdrive clutch, reduction brake <5A/T>

diagnosis code 44: Overdrive clutch, second brake <4A/T>, underdrive clutch <5A/T>, direct clutch <5A/T>

diagnosis code 45: Overdrive clutch, second brake, direct clutch

diagnosis code 46: Reverse clutch, low-reverse brake

OK: Refer to Hydraulic Pressure Test

Q: Is the check result normal?

YES: Go to Step 6

.
NO <some hydraulic pressures are abnormal>: Go to Step 5

.
NO <all hydraulic pressure are abnormal>: Go to Step 4

STEP 4. Adjust the line pressure and recheck the diagnosis code.

Adjust the line pressure (Refer to ).

Test drive the vehicle.

Check the diagnosis code.

Q: Is the diagnosis code set?

YES: Go to Step 5

.
NO: The inspection is complete.

STEP 5. Disassemble, clean and assemble the valve body and recheck the diagnosis code.

Check the mounting bolts for looseness, and the O-ring, solenoid valve and valve body for damage.
Replace the valve body assembly if the damages are thought to be irreparable.

Test drive the vehicle.

Check the diagnosis code.

Q: Is the diagnosis code set?

YES: Go to Step 7

.
NO: The inspection is complete.

STEP 6. Replace the engine-A/T-ECU and then recheck the diagnosis code.

Replace the engine-A/T-ECU.

Test drive the vehicle.

Check the diagnosis code.

Q: Is the diagnosis code set?

YES: Go to Step 7

.
NO: The inspection is complete.

STEP 7. Check the A/T internal clutch and brake, and then recheck the diagnosis code.

Check the following clutches or brakes according to the output diagnosis codes, replace if necessary.

If diagnosis code 41, 42, 43, 44 <5A/T> are output individually or in a group, replace the underdrive clutch.

If diagnosis code 43, 44, 45 <5A/T> are output individually or in a group, replace the overdrive clutch.

If diagnosis code 44, 45 are output individually or in a group, replace the direct clutch <5A/T>.

If diagnosis code 46 is output, replace the reverse clutch.

If diagnosis code 41, 46 are output individually or in a group, replace the low-reverse brake.

If diagnosis code 42, 44 <4A/T>, 45 <5A/T> are output individually or in a group, replace the second brake.

If diagnosis code 41, 42 <5A/T>, 43 <5A/T> are output, replace the one-way clutch.

Test drive the vehicle.

Check the diagnosis code.

Q: Is the diagnosis code set?

YES: Eliminate the cause of the noise.
NO: The inspection is complete.



Code No. 41 (1st), 42 (2nd), 43 (3rd), 44 (4th), 45 (5th) <5A/T>, 46 (reverse): Gear Incorrect Ratio


OPERATION The engine-A/T-ECU detects the current gear/speed according to the output signals from the input and output shaft speed sensor.
DIAGNOSIS CODE SET CONDITIONS If the output from the output shaft speed sensor multiplied by the gear ratio is not the same as the output from the input shaft speed sensor after completing of shifting, the corresponding diagnosis code is output. If each diagnosis code is output 4 times, the transmission is fixed in 3rd as a fail-safe measure.
PROBABLE CAUSES Malfunction of input shaft speed sensor Malfunction of output shaft speed sensor Damaged harness wires and connectors Malfunction of the engine-A/T-ECU Malfunction of solenoid valve Malfunction of underdrive clutch retainer Malfunction of valve body Malfunction of transfer drive gear or driven gear <4A/T> Malfunction of direct planetary carrier <5A/T> Malfunction of low-reverse brake system (for diagnosis codes 41, 46) Malfunction of underdrive clutch system (for diagnosis codes 41, 42, 43, 44 <5A/T>) Malfunction of second brake system (for diagnosis codes 42, 44 <4A/T>, 45 <5A/T>) Malfunction of overdrive clutch system (for diagnosis codes 43, 44, 45 <5A/T>) Malfunction of reduction brake system <5A/T> (for diagnosis codes 41, 42, 43, 46) Malfunction of direct clutch system <5A/T> (for diagnosis codes 44, 45) Malfunction of reverse clutch system (for diagnosis code 46) Malfunction of one-way clutch system (for diagnosis code 41)
DIAGNOSIS PROCEDURE

STEP 1. MUT-II/III diagnosis code Either of diagnosis codes 41, 42, 43, 44, 45 <5A/T> or 46 is output, the input shaft speed sensor or output shaft speed sensor is defective. Q: Are diagnosis codes 22 or 23 output? YES <diagnosis code 22 is output>: Refer to diagnosis code 22: Input shaft speed sensor system . YES <diagnosis code 23 is output>: Refer to diagnosis code 23: Output shaft speed sensor system . NO: Go to Step 2.
STEP 2. MUT-II/III diagnosis code Either of diagnosis codes 41, 42, 43, 44, 45 <5A/T> or 46 is output, the corresponding solenoid valve is defective. Q: Is either of diagnosis code 31, 32, 33, 34, 35 <5A/T> output? YES <diagnosis code 31 is output>: Refer to diagnosis code: 31 Low-reverse solenoid valve system . YES <diagnosis code 32 is output>: Refer to diagnosis code 32: Underdrive solenoid valve system . YES <diagnosis code 33 is output>: Refer to diagnosis code 33: Second solenoid valve system . YES <diagnosis code 34 is output>: Refer to diagnosis code 34: Overdrive solenoid valve system . YES <diagnosis code 35 is output>: Refer to diagnosis code 35: Reduction solenoid valve system . NO: Go to Step 3.
STEP 3. Hydraulic pressure test Each hydraulic pressure of the elements below, which diagnosis codes indicate, should be within the standard value. diagnosis code 41: Underdrive clutch, low-reverse brake, reduction brake <5A/T> diagnosis code 42: Underdrive clutch, low-reverse brake, reduction brake <5A/T> diagnosis code 43: Underdrive clutch, overdrive clutch, reduction brake <5A/T> diagnosis code 44: Overdrive clutch, second brake <4A/T>, underdrive clutch <5A/T>, direct clutch <5A/T> diagnosis code 45: Overdrive clutch, second brake, direct clutch diagnosis code 46: Reverse clutch, low-reverse brake OK: Refer to Hydraulic Pressure Test . Q: Is the check result normal? YES: Go to Step 6. NO <some hydraulic pressures are abnormal>: Go to Step 5. NO <all hydraulic pressure are abnormal>: Go to Step 4.
STEP 4. Adjust the line pressure and recheck the diagnosis code. Adjust the line pressure (Refer to ). Test drive the vehicle. Check the diagnosis code. Q: Is the diagnosis code set? YES: Go to Step 5. NO: The inspection is complete.
STEP 5. Disassemble, clean and assemble the valve body and recheck the diagnosis code. Check the mounting bolts for looseness, and the O-ring, solenoid valve and valve body for damage. Replace the valve body assembly if the damages are thought to be irreparable. Test drive the vehicle. Check the diagnosis code. Q: Is the diagnosis code set? YES: Go to Step 7 . NO: The inspection is complete.
STEP 6. Replace the engine-A/T-ECU and then recheck the diagnosis code. Replace the engine-A/T-ECU. Test drive the vehicle. Check the diagnosis code. Q: Is the diagnosis code set? YES: Go to Step 7 . NO: The inspection is complete.
STEP 7. Check the A/T internal clutch and brake, and then recheck the diagnosis code. Check the following clutches or brakes according to the output diagnosis codes, replace if necessary. If diagnosis code 41, 42, 43, 44 <5A/T> are output individually or in a group, replace the underdrive clutch. If diagnosis code 43, 44, 45 <5A/T> are output individually or in a group, replace the overdrive clutch. If diagnosis code 44, 45 are output individually or in a group, replace the direct clutch <5A/T>. If diagnosis code 46 is output, replace the reverse clutch. If diagnosis code 41, 46 are output individually or in a group, replace the low-reverse brake. If diagnosis code 42, 44 <4A/T>, 45 <5A/T> are output individually or in a group, replace the second brake. If diagnosis code 41, 42 <5A/T>, 43 <5A/T> are output, replace the one-way clutch. Test drive the vehicle. Check the diagnosis code. Q: Is the diagnosis code set? YES: Eliminate the cause of the noise. NO: The inspection is complete.