Isuzu KB P190. Manual — part 1014

7A2-90 TRANSMISSION CONTROL SYSTEM (AW30–40LE)

DTC P0962 or P0963 (Flash Code 35)

RTW77ALF001501

Circuit Description

The pressure control solenoid is a PWM duty control
solenoid located in the valve body.

The pressure control solenoid is a TCM-controled
device used to regulate transmission throttle pressure
by energizing current from the TCM.

Condition For Running The DTC

All of the following conditions are met.

(1) All of the following conditions are met for 2

seconds or more continuously.

• The supply voltage is more than 10.2 volts and

less than 15.5 volts.

(2) Not emergency mode.

(3) All of the following conditions are met.

• Device Control is not operating.

• Disable Normal Communication Service is

receiving enable.

• DTC Clear is not operating.

Condition For Setting The DTC

(1) All of the following conditions are met for 12.5

seconds or more continuously. (DTC P0962)

• 1 second or more passed after ignition short

failure detection condition is met or ignition short
failure is never detected after ignition “ON”.

TRANSMISSION CONTROL SYSTEM (AW30–40LE) 7A2-91

• Feedback current value is less than 92 mA

(2) All of the following conditions are met for 0.5

seconds or more continuously. (DTC P0963)

• 1 second or more passed after open failure

detection condition is met or open failure is not
detected after ignition “ON”.

• Feedback current value is more than 1357 mA.

Action Taken When The DTC Sets

• No squat control.

• No line pressure reduction control at gear change.

• No lock-up control.

• No slope control.

• No torque reduction control.

• No line pressure reduction control at garage.

• Line pressure FULL output.

• No shift solenoid functional failure detection.

• No L-up solenoid functional failure detection.

• No pressure control solenoid Feedback stuck failure

detection.

• Check Trans “ON”.

• DTC

stored.

• MIL request “ON”. (EURO 4 only)

Conditions For Clearing The DTC

• The DTC can be cleared from the TCM history by

using a scan tool.

• The DTC will be cleared from history when the

vehicle has achieved 40 warm-up cycles without a
failure reported.

• After more than 1 second has elapsed after the

ignition key has been turned “ON”, short between
No.11 and No.4 (ground) of DLC (Data Link
Connector). Then, after 1 second, but within 6
seconds, discontinue shorting.

Diagnostic Aids

• Inspect the wiring for poor electrical connection at the

TCM. Look for possible bent, backed out, deformed
or damaged terminals. Check for weak terminal
tension as well. Also check for a chafed wire that
could short to bare metal or other wiring.

Inspect for a broken wire inside the insulation.

• When diagnosing for a possible intermittent short or

open condition, move the wiring harness while
observing test equipment for a change.

Circuit/System Testing DTC P0962 or P0963

Step Action Value(s)

YES

NO

1

Was the On-Board Diagnostic (OBD) System Check
performed?

— Go

to

Step 2

Go to OBD

System Check

2

1. Install a scan tool.

2. Turn “ON” the ignition.

3. Record scan tool data.

4. Operate the vehicle within scan tool data.

Does a scan tool indicate DTC P0962 or P0963?

— Go

to

Step 3

Refer to

Diagnostic Aids

3

Measure the resistance of pressure control solenoid.

1. Turn “OFF” the ignition.

2. Disconnect the automatic transmission connector.

3.

Measure the resistance between automatic
transmission terminal E54-2 and automatic
transmission terminal E54-6.

Is the resistance specified value?

5 to 5.6

Ω

at

20

°C (68°F)

Go to Step 4

Go to Step 7

7A2-92 TRANSMISSION CONTROL SYSTEM (AW30–40LE)

Step Action Value(s)

YES

NO

4

Measure the resistance of wire between terminal C94-
2 and terminal C94-4

1. Turn “OFF” the ignition.

2. Connect the automatic transmission connector.

3. Disconnect the TCM connector.

4. Measure the resistance between terminal C94-2

and terminal C94-4.

Is the resistance specified value?

5 to 5.6

Ω

at

20

°C (68°F)

Go to Step 6

Go to Step 5

5

Repair or Replace the wire between terminals C94-2,
4 and terminals E54-6, 2.

Is the action complete?

— Go

to

Step 9 —

6

Observe the PCS Actual Current data on a scan tool
data.

1. Turn “ON” the ignition.

Does the scan tool indicate is specified value?

About

1000mA

Go to Step 9 Go

to

Step 8

7

Replace the pressure control solenoid.

Is the action complete?

— Go

to

Step 9 —

8

Replace the TCM.

Important:

The replacement TCM must be

programmed (Refer to SPS for procedure).

Is the action complete?

— Go

to

Step 9 —

9

1. Reconnect all previously disconnected harness

connector(s).

2. Clear the DTCs with a scan tool.

3. Turn “OFF” the ignition.

4. Start the engine.

5. Operate the vehicle within the Conditions For

Running the DTC. You may also operate the
vehicle within the conditions that you observed
from the Freeze Frame/ Failure Records.

Did the DTC fail this ignition?

—

Go to Step 2 Go

to

Step 10

10

Observe the stored information, Capture info with a
scan tool.

Are there any DTCs that you have not diagnosed?

—

Go to

Diagnostic

Trouble Code

(DTC) List

Verify repair

TRANSMISSION CONTROL SYSTEM (AW30–40LE) 7A2-93

DTC P0973 or P0974 (Flash Code 31)

RTW77ALF001501

Circuit Description

The shift solenoid S1 changes the hydraulic route with
the signals from the TCM according to the vehicle
speed and the throttle opening to control shifting. When
the shift solenoid S1 or S2 fails, the hydraulic circuit is
mechanically operated as a backup.

Condition For Running The DTC

All of the following conditions are met.

(1) All of the following conditions are met for 2

seconds or more continuously.

• The supply voltage is more than 10.2 volts and

less than 15.5 volts.

(2) Not emergency mode.

(3) 0.025 seconds or more passed after the state of

power “ON” solenoid is changed.

(4) All of the following conditions are met.

• Device Control is not operating.

• Disable Normal Communication is receiving

enable.

• DTC Clear is not operating.