Page 4058 of 6020

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 5.6Ω 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
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
Page 4061 of 6020

TRANSMISSION CONTROL SYSTEM (AW30–40LE) 7A2-95
Step Action Value(s) YES NO
4 1. Turn “OFF” the ignition.
2. Disconnect the TCM connector (C-94).
3. Turn “ON” the ignition.
4. Measure the voltage between terminal C94-16 and terminal C94-1 by 5-8840-0285-0 DMM.
Is the voltage specified value? 0V Go to
Step 5 Go to Step 7
5 1. Turn “OFF” the ignition.
2. Measure the resistance between terminal C94-16
and body ground by 5-8840-0285-0 DMM.
Is the resistance specified value? 11
∼15 Ω Go to Step 9 Go to Step 6
6 1. Disconnect the automatic transmission connector
(E-54).
2. Measure the resistance between terminal E54-4
and body ground by 5-8840-0285-0 DMM.
Is the resistance specified value? 11
∼15 Ω Go to Step 7 Go to Step 8
7 1. Check for open or short in the wire between
terminal C94-16 and terminal E54-4.
2. Repair or replace the wire between terminal C94-
16 and terminal E54-4.
Is the action complete? — Go to
Step 11 —
8 Replace the S1 solenoid.
Is the action complete? — Go to
Step 11 —
9 1. Clear the DTC.
2. Perform the test-driving.
3. Check the DTC.
W as DTC P0973 or P0974 stored? — Go to
Step 10 Refer to
Diagnostic Aids
10 Replace the TCM.
Important: The replacement TCM must be
programmed (Refer to SPS for procedure).
Is the action complete? — Go to
Step 11 —
11 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 12
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
Page 4066 of 6020
7A2-100 TRANSMISSION CONTROL SYSTEM (AW30–40LE)
Step Action Value(s) YES NO
11 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 12
12 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
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
Page 4068 of 6020

7A2-102 TRANSMISSION CONTROL SYSTEM (AW30–40LE)
Circuit/System Testing DTC P1790
Step Action Value(s) YES NO
1
W as 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 “OFF” the ignition and keep the position for
more than 30 seconds.
3. Turn “ON” the ignition.
4. Check the DTC on a scan tool.
Does a scan tool indicate DTC P1791? — Go to
Step 3 Refer to
Diagnostic Aids
3 Perform the SPS for the TCM.
Is the action complete? — Go to
Step 4 —
4 Recheck the DTC on the scan tool.
Does the scan tool indicate DTC P1790? — Go to
Step 5 Go to Step 6
5 Replace the TCM.
Important: The replacement TCM must be
programmed (Refer to SPS for procedure).
Is the action complete? — Go to
Step 6 —
6 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 7
7 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
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
Page 4070 of 6020

7A2-104 TRANSMISSION CONTROL SYSTEM (AW30–40LE)
Circuit/System Testing DTC P1791
Step Action Value(s) YES NO
1
W as 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 “OFF” the ignition and keep the position for
more than 30 seconds.
3. Turn “ON” the ignition.
4. Check the DTC on the scan tool.
Does a scan tool indicate DTC P1791? — Go to
Step 3 Refer to
Diagnostic Aids
3 Replace the TCM.
Important: The replacement TCM must be
programmed (Refer to SPS for procedure).
Is the action complete? — Go to
Step 4 —
4 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 5
5 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
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
Page 4074 of 6020
7A2-108 TRANSMISSION CONTROL SYSTEM (AW30–40LE)
Step Action Value(s) YES NO
11 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 12
12 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
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
Page 4076 of 6020

7A2-110 TRANSMISSION CONTROL SYSTEM (AW30–40LE)
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.
• W hen diagnosing for a possible intermittent short o
r
open condition, move the wiring harness while
observing test equipment for a change.
Circuit/System Testing DTC P2773 or P2774
Step Action Value(s) YES NO
1
W as 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. Review and record scan tool data.
4. Operate the vehicle within scan tool data.
Does a scan tool indicate DTC P2773 or P2774? — Go to
Step 3 Refer to
Diagnostic Aids
3 Observe the 4L signal data of the TCM on the scan tool.
1. Turn “ON” the ignition with engine “ON”.
2. Perform the road testing.
3. Check the 4L signal data on a scan tool.
W as the problem found? — Go to
Step 4 Refer to
Diagnostic Aids
4 Observe the 4L signal data of the TCM on a scan tool.
1. Turn “ON” the ignition with engine “ON”.
2. Perform the road testing.
3. Check the 4L signal data on a scan tool.
Is the 4L signal fixed “ON”? (DTC P2773) — Go to
Step 6 Go to Step 5
5 Observe the 4L signal data of the TCM on a scan tool.
1. Turn “ON” the ignition with engine “ON”.
2. Perform the road testing.
3. Check the 4L signal data on a scan tool.
Is the 4L signal fixed “OFF”? (DTC P2774) — Go to
Step 6 Go to Step 8
6 Replace or Repair the wire between the TCM terminal
C94-21 and the T/F control unit terminal C111-7.
Is the action complete? — Go to
Step 9 —
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007
Page 4077 of 6020
TRANSMISSION CONTROL SYSTEM (AW30–40LE) 7A2-111
Step Action Value(s) YES NO
7 Replace the T/F Control Unit. — 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
BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007