FixVault

DTC P0746

DTC P0746:  A/T Clutch Pressure Control Solenoid Valve A Stuck OFF

General Description 

GHH465314Courtesy of HONDA, U.S.A., INC.
Hydraulic pressure supply to clutch or piston by shift solenoid valve output

Gear position  Shift solenoid valve  Clutch  Piston 
A B C D E Secondary Main Reverse 1 3 5 7 2 4 6 8
Park or Neutral  O O X X X - - - - - - - - - - -
Neutral → Reverse  O O X X O - - B - - A - - - - -
Reverse  O O O X O - - PL - - A - - - - -
Odd gear engaged and lock-up OFF  X O O X X A B - - - - - - - C B
Odd gear engaged and lock-up ON  X X O X X A B - - - - - - D C -
Even gear engaged and lock-up OFF  O X X X X A B - - - D - - - - -
Even gear engaged and lock-up ON  X X X X X A B - - C D - - - - -
Secondary clutch and main clutch switching  X X X X X A B - - C D - - - - -
Neutral → 1st or 3rd → Neutral  X X X O X A B - C - D - - - - -
Neutral → 3rd or 1st → Neutral  X X X X X A B - - C D - - - - -
Neutral → 5th or 7th → Neutral  X X X X X A B - - C D - - - - -
Neutral → 7th or 5th → Neutral  X X X X O A B - - C - D - - - -
Neutral → 2nd or 4th → Neutral  X X O X O A B - - - - - D - C -
Neutral → 4th or 2nd → Neutral  X X O X X A B - - - - - - D C -
Neutral → 6th or 8th → Neutral  X X O X X A B - - - - - - D C -
Neutral → 8th or 6th → Neutral  X X O O X A B - - - - - - D - C

O: Shift solenoid valve ON

X: Shift solenoid valve OFF

A: Clutch pressure control solenoid valve A pressure

B: Clutch pressure control solenoid valve B pressure

C: Clutch pressure control solenoid valve C pressure

D: Clutch pressure control solenoid valve D pressure

PL: Line pressure

Clutch pressure control solenoid valve A is used for clutch or piston pressure control. A spool in clutch pressure control solenoid valve A pushes the valve according to the duty cycle that is controlled by the powertrain control module (PCM) (The hydraulic pressure is proportional to the current). The hydraulic pressure provided to the clutch or to the piston is switched by the shift valves. The PCM uses the output values of the odd clutch pressure sensor to detect malfunction. If the odd clutch pressure sensor outputs abnormal value from the commanded one, the PCM detects a clutch pressure control solenoid valve A stuck OFF failure and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status 

Execution Continuous
Sequence None
Duration 2 seconds or less
DTC Type Two drive cycles, MIL on, A/T gear position indicator blinks
OBD Status PASSED/FAILED/NOT COMPLETED (STILL TESTING)

Enable Conditions 

Condition Minimum Maximum
Engine speed [Engine Speed] 500 RPM -
Battery voltage [Battery Voltage] 11 V -
No active DTCs set (prevents monitor from running) P0716, P0717, P0718, P0721, P0722, P0723, P0747, P0751, P0752, P0756, P0757, P0761, P0762, P0766, P0767, P0771, P0772, P0776, P0777, P0792, P0793, P0794, P0796, P0797, P0841, P0842, P0843, P0846, P0847, P0848, P0871, P0872, P0873, P0962, P0963, P0966, P0967, P0970, P0971, P0973, P0974, P0976, P0977, P0979, P0980, P0982, P0983, P0985, P0986, P2714, P2715, P2720, P2721, P2729, P2730, P2746, P2747, P2748, P2820, P2821, P2826, P2827, P2832, P2833, P2834, P2837, P2838, P2839, P283C, P283D, P283E, P2841, P2842, P2843, P2845, P2846, P2847, P2848

[ ]: HDS Parameter

Malfunction Threshold 

Either of the following symptoms occurs at each PCM command control:

PCM command control Symptom
2nd gear engagement or 4th gear disengagement control (secondary clutch engaged) Low secondary clutch pressure
4th gear engagement or 2nd gear disengagement control (secondary clutch engaged)
6th gear engagement or 8th gear disengagement control (secondary clutch engaged)
8th gear engagement or 6th gear disengagement control (secondary clutch engaged)
Driving in odd gear
Secondary clutch and main clutch switching control (secondary clutch disengaged → main clutch engaged)
Secondary clutch and main clutch switching control (main clutch disengaged → secondary clutch engaged)

Judgment condition of low secondary clutch pressure: Odd clutch pressure sensor output value is less than 100 kPa (1.02 kgf/cm2, 15 psi).

Possible Cause 

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

Confirmation Procedure 

With the HDS 

None.

With the Driving Pattern 

  1. Start the engine.
  2. Drive the vehicle in 1st gear for at least 2 seconds.

Diagnosis Details 

Conditions for setting the DTC 

When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC 

The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.