DTC Advanced Diagnostics: P0747
DTC P0747:A/T Clutch Pressure Control Solenoid Valve A Stuck ON

General Description
Hydraulic pressure supply to the clutch by shift solenoid valve output (D position)
Gear position
Shift solenoid valve
Clutch
A
B
1st
2nd
3rd
4th
5th
6th
Neutral-1st
ON
OFF
CPCD
–
–
–
–
–
1st
ON
ON
LINE
CPCA
CPCB
CPCC
–
–
1st-2nd
ON
ON
LINE
CPCA
CPCB
CPCC
–
–
2nd
ON
ON
LINE
CPCA
CPCB
CPCC
–
–
2nd-3rd
ON
ON
LINE
CPCA
CPCB
CPCC
–
–
3rd
OFF
ON
LINE
–
CPCB
CPCC
CPCA
–
3rd-4th
OFF
ON
LINE
–
CPCB
CPCC
CPCA
–
4th
OFF
OFF/(ON)
LINE
–
(CPCB)
CPCC
CPCA
CPCB
4th-5th
OFF
OFF
LINE
–
–
CPCC
CPCA
CPCB
5th
OFF
OFF/(ON)
LINE
–
(CPCB)
CPCC
CPCA
CPCB
5th-6th
OFF
OFF
LINE
–
–
CPCC
CPCA
CPCB
6th
OFF
OFF
LINE
–
–
CPCC
CPCA
CPCB
LINE: Line pressure

CPCA: A/T clutch pressure control solenoid valve A pressure

CPCB: A/T clutch pressure control solenoid valve B pressure

CPCC: A/T clutch pressure control solenoid valve C pressure

CPCD: A/T clutch pressure control solenoid valve D pressure

A/T clutch pressure control solenoid valve A is installed on the transmission housing. A/T clutch pressure control solenoid valve A is operated by the powertrain control module (PCM) and converts line pressure to A/T clutch pressure control solenoid valve A pressure. A signal from the PCM is output to A/T clutch pressure control solenoid valve A to supply proper A/T clutch pressure control solenoid valve A pressure to the correct gear clutch according to the shift schedule and the driving conditions. When the current from the PCM is high (ON), A/T clutch pressure control solenoid valve A operates and A/T clutch pressure control solenoid valve A pressure increases. When the current from the PCM is low (OFF), A/T clutch pressure control solenoid valve A turns off and A/T clutch pressure control solenoid valve A pressure decreases. The PCM monitors the input shaft (mainshaft) speed and the output shaft (countershaft) speed according to the shift status determined by the shift schedule, and monitors the transmission fluid pressure switch according to the shift status determined by the shift schedule. When an improper gear ratio is output for the shift schedule or when the wrong transmission fluid pressure switch is on for the shift schedule, the PCM detects an A/T clutch pressure control solenoid valve A stuck on failure and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status
Execution
Continuous
Sequence
None
Duration
Symptom 1
21 seconds or more
Symptom 2
Symptom 3
6 seconds or more
Symptom 4
Symptom 5
3 seconds or more
Symptom 6
Symptom 7
Symptom 8
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
ATF temperature
[ATF Temperature]
-4 °F (-20 °C)
–
Vehicle speed
[VEHICLE SPEED]
5 mph (9 km/h)
–
Battery voltage
[BATTERY VOLTAGE]
11 V
–
Shift lever position
D
No active DTCs set (prevents monitor from running)
P0122, P0123, P0222, P0223, P0300, P0301, P0302, P0303, P0304, P0305, P0306, P0351, P0352, P0353, P0354, P0355, P0356, P0705, P0716, P0717, P0718, P0721, P0722, P0723, P0746, P0751, P0752, P0756, P0757, P0761, P0762, P0776, P0777, P0796, P0797, P0842, P0843, P0847, P0848, P0872, P0873, P0877, P0878, P0962, P0963, P0966, P0967, P0970, P0971, P0973, P0974, P0976, P0977, P0979, P0980, P0989, P0990, P1658, P1659, P1683, P1684, P2101, P2118, P2122, P2123, P2127, P2128, P2135, P2138, P2176, P2648, P2649, P2653, P2654, P2658, P2659, P2714, P2720, P2721
[ ]: HDS Parameter

Malfunction Threshold
One of these conditions occurs:
Either Symptom 1, Symptom 2, Symptom 3, or Symptom 4 occurs.
The input signal from transmission fluid pressure switch A (2nd clutch) to the PCM is off for at least 4 seconds when the 5th gear shift is commanded or when the shift lever is in P, R, or N, after Symptom 5 occurred.
The input signal from transmission fluid pressure switch D (5th clutch) to the PCM is off for at least 4 seconds when the 2nd gear shift is commanded or when the shift lever is in P, R, or N, after Symptom 6, Symptom 7, or Symptom 8 occurred.

Symptom 1
Symptom
Gear position commanded by the PCM
Actual gear position
1
2nd ? 3rd gear upshift
Driving in 2nd gear

Symptom 2
Symptom
Gear position commanded by the PCM
Actual gear position
2
5th ? 6th gear upshift
Driving in 5th gear

Symptom 3
Symptom
Gear position commanded by the PCM
Actual gear position
3
5th ? 4th gear downshift
Driving in 5th gear

Symptom 4
Symptom
Gear position commanded by the PCM
Actual gear position
4
5th ? 3rd gear downshift
Driving in 5th gear

Symptom 5
Symptom
Gear position commanded by the PCM
Actual gear position
5
Driving in 1st gear
Turn on transmission fluid pressure switch A (2nd clutch) when driving in 1st gear

Symptom 6
Symptom
Gear position commanded by the PCM
Actual gear position
6
Driving in 3rd gear
Turn on transmission fluid pressure switch D (5th clutch) when driving in 3rd gear

Symptom 7
Symptom
Gear position commanded by the PCM
Actual gear position
7
Driving in 4th gear
Turn on transmission fluid pressure switch D (5th clutch) when driving in 4th gear

Symptom 8
Symptom
Gear position commanded by the PCM
Actual gear position
8
Driving in 6th gear
Turn on transmission fluid pressure switch D (5th clutch) when driving in 6th gear

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.
A/T clutch pressure control solenoid valve A stuck on

Confirmation Procedure
Operating Condition
1.
Start the engine.
2.
Drive the vehicle in D until the transmission shifts into 6th gear.
Drive the vehicle in this manner only if the traffic regulations and ambient conditions allow.
With the HDS
None.

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, the A/T gear position indicator blinks, and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC
The A/T gear position indicator comes off by pressing the engine start/stop button to select the OFF mode. 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.