Lexus ES: Pressure Control Solenoid "A" Circuit Short to Battery (P074512)

Lexus ES (XZ10) Service Manual / Drivetrain / Ua80e (automatic Transmission / Transaxle) / Automatic Transaxle System / Pressure Control Solenoid "A" Circuit Short to Battery (P074512)

DESCRIPTION

Changing gears is performed by the ECM turning the solenoid (SL1, SL2, SL3, SL4, SL5 and SL6) valves on and off.

If an open or short occurs in any of the solenoid valve circuits, the ECM controls the remaining normal solenoid valves to allow the vehicle to be driven. If all of the solenoid valves are malfunctioning, only the mechanical fluid pressure circuit will function and some manual operation will be possible. If an open or short occurs in a solenoid valve circuit, the ECM cuts power to the malfunctioning solenoid valve.

HINT:

The following table shows normal operation of the solenoid (SL1) valve when the shift lever is in D.

Solenoid Valve Operation:

Gear	1st	2nd	3rd	4th	5th	6th	7th	8th
Solenoid (SL1) Valve	ON	ON	ON	ON	ON	OFF	OFF	OFF

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	MIL	Memory	Note
P074512	Pressure Control Solenoid "A" Circuit Short to Battery	While the vehicle is being driven so that gear changes occur, a short to +B is detected in the solenoid (SL1) valve circuit for 1 second (1-trip detection logic).	Solenoid (SL1) valve Transmission wire Harness and connector ECM	Comes on	DTC stored	SAE Code: P0963

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

Note

P074512

Pressure Control Solenoid "A" Circuit Short to Battery

While the vehicle is being driven so that gear changes occur, a short to +B is detected in the solenoid (SL1) valve circuit for 1 second (1-trip detection logic).

Solenoid (SL1) valve
Transmission wire
Harness and connector
ECM

Comes on

DTC stored

SAE Code:

P0963

MONITOR DESCRIPTION

This DTC indicates a short to +B in the solenoid (SL1) valve circuit. The ECM commands gear shifts by turning the solenoid valves on or off. When there is an open or short in any solenoid valve circuit, the ECM detects the problem, illuminates the MIL and stores a DTC.

The ECM performs the fail-safe function and turns the other normal solenoid valves on or off. In the case of an open or short circuit, the ECM stops sending current to the open or shorted solenoid.

MONITOR STRATEGY

Related DTCs	P0963: Solenoid (SL1) valve/Range check (High current)
Required sensors/components	Solenoid (SL1) valve
Frequency of operation	Continuous
Duration	1 sec.
MIL operation	Immediate
Sequence of operation	None

TYPICAL ENABLING CONDITIONS

All

The monitor will run whenever the following DTCs are not stored	None
Solenoid current cut status	Not cut
Engine switch	On (IG)
Starter	OFF
Battery voltage	10.5 V or more

Condition (A)

Battery voltage	8 V or more and less than 12.499 V
Target current (0.1 sec. or more)	0.8 A or less

Condition (B)

Battery voltage	12.5 V or more and less than 16 V
Target current (0 sec. or more)	1 A or less

TYPICAL MALFUNCTION THRESHOLDS

Any of the following conditions are met: Condition (A) or (B)

Condition (A)

Battery voltage	8 V or more and less than 12.499 V
Solenoid current	More than 0.92 A

Condition (B)

Battery voltage	12.5 V or more and less than 16 V
Solenoid current	More than 1.1 A

COMPONENT OPERATING RANGE

Both of the following conditions are met: Condition (A) and (B)

Condition (A)

Battery voltage	8 V or more and less than 12.499 V
Solenoid current	0.92 A or less

Condition (B)

Battery voltage	12.5 V or more and less than 16 V
Solenoid current	1.1 A or less

CONFIRMATION DRIVING PATTERN

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

HINT:

After repairs have been completed, clear the DTCs and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.
When clearing the permanent DTCs, refer to the Clear Permanent DTC procedure.
Click here

Connect the Techstream to the DLC3.
Turn the engine switch on (IG) and turn the Techstream on.
Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
Turn the engine switch off and wait for 2 minutes or more.
Turn the engine switch on (IG) and turn the Techstream on.
Start the engine.
Perform the D Position Shift Test inspection in Road Test. [*1]
Click here

HINT:

[*1] : Normal judgment procedure.

The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.
Stop the vehicle.
Enter the following menus: Powertrain / Transmission / Utility / All Readiness.
Input the DTC: P074512.

Check the DTC judgment result.

Techstream Display	Description
NORMAL	DTC judgment completed System normal
ABNORMAL	DTC judgment completed System abnormal
INCOMPLETE	DTC judgment not completed Perform driving pattern after confirming DTC enabling conditions
N/A	Unable to perform DTC judgment Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

HINT:

If the judgment result shows NORMAL, the system is normal.
If the judgment result shows ABNORMAL, the system has a malfunction.
If the judgment result shows INCOMPLETE or N/A, perform the normal judgment procedure again.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Perform the universal trip to clear permanent DTCs.
Click here
Perform registration and/or initialization when parts related to the automatic transaxle are replaced.
Click here

PROCEDURE

1.	CHECK HARNESS AND TRANSMISSION WIRE (TRANSMISSION WIRE (SOLENOID (SL1) VALVE) - ECM)

(a) Disconnect the C32 ECM connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection	Condition	Specified Condition
C32-12 (SL1+) or C32-13 (SL1-) - Other terminals	Always	10 kΩ or higher

GO TO STEP 3

2.	REPLACE ECM

(a) Replace the ECM.

Click here

PERFORM REGISTRATION

3.	CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM)

(a) Disconnect the C30 transmission wire connector.

(b) Disconnect the C32 ECM connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
C30-17 (SL1+) or C32-12 (SL1+) - Other terminals	Always	10 kΩ or higher
C30-16 (SL1-) or C32-13 (SL1-) - Other terminals	Always	10 kΩ or higher

REPAIR OR REPLACE HARNESS OR CONNECTOR (TRANSMISSION WIRE - ECM)

4.	INSPECT SOLENOID (SL1) VALVE

(a) Remove the solenoid (SL1) valve.

Click here

*a	Component without harness connected (Solenoid (SL1) Valve)

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection	Condition	Specified Condition
Solenoid (SL1) valve connector terminal 1 - terminal 2	20°C (68°F)	5.0 to 5.6 Ω

(c) Connect a positive (+) lead from the battery with a 21 W bulb to terminal 1 and a negative (-) lead to terminal 2 of the solenoid valve connector. Check that the valve moves and makes an operating sound.

OK:

Valve moves and makes an operating sound.

REPAIR OR REPLACE TRANSMISSION WIRE

REPLACE SOLENOID (SL1) VALVE

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