2007 ISUZU KB P190 check engine

TRANSMISSION CONTROL SYSTEM (AW30–40LE) 7A2-87

(5) Engine coolant temperature sensor is not detecting failure or not deciding failure.
(6) Engine revolution rpm is more than 600 rpm.
(7) Engine revolution sensor is not detecting failure o
r
not deciding failure.
(8) T/F condition is high.
(9) T/F Hi-Low SW is not detecting failure or not deciding failure.
(10) Output revolution sensor is not detecting failure o
r
not deciding failure.
(11) S1 solenoid is not detecting failure or not deciding
failure. (Electric failure)
(12) S2 solenoid is not detecting failure or not deciding
failure. (Electric failure)
(13) Selector position switch is not detecting failure o
r
not deciding failure.
(14) DTC U2104 is not detecting failure or not deciding
failure.
(15) DTC U2105 is not detecting failure or not deciding
failure.
(16) Input revolution sensor is not deciding.
(17) Throttle signal is not detecting failure or not
deciding failure.
(18) Not emergency mode.
(19) Engine torque signal is not detecting failure or not
deciding failure.
(20) Pressure control solenoid is not detecting failure o
r
not deciding failure.
(21) 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
The following conditions are detected two times or more
between ignition “ON” and ignition “OFF”.
2 second passed after gear change output.
• The TCM detects equivalent of 2nd gear ratio for 1 second in case of 1st gear output.
- The throttle position is more than 8% and less than 100%.
- The vehicle speed is more than 5 km/h (3 mph).

• The TCM detects equivalent of 3rd gear ratio for 1
second in case of 4th gear output.
- The throttle position is more than 8% and less than 100%.
- The vehicle speed is more than 5 km/h (3 mph).
Action Taken When The DTC Sets
• No input revolution sensor failure detection.
• MIL request “ON”. (EURO 4 only)
• Check Trans “ON”.
• DTC stored.
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.


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ISUZU KB P190 2007

7A2-88 TRANSMISSION CONTROL SYSTEM (AW30–40LE)

Circuit/System Testing DTC P0757
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 P0757? — Go to
Step 3 Refer to
Diagnostic Aids
3 Perform the transmission fluid checking procedure.
Refer to checking Transmission Fluid level and
Condition in Automatic Transmission 7A section.
If the problem found, repair or replace necessary.

W as the problem found? — Go to
Step 8 Go to Step 4
4 Observe the commanded gear and current gear on
the scan tool.
1. Turn “ON” the ignition with engine “ON”.
2. Road testing the vehicle.
3. The throttle position is more than 8%.
4. The vehicle speed is more than 5 km/h (3 mph).

Did the TCM detect 2nd gear ratio in case of 1st gear
target, and 3rd gear ratio in case of 4th gear target?
Above conditions were indicated on the scan tool
display? — Refer to
Diagnostic Aids Go to
Step 5
5 Check the following items.
• Check the shift solenoid valve S2. (Refer to
Section 7A3)
• Shift solenoid valve S2 stuck “ON” the release
position (Refer to Section 7A4)
• Misaligned or damaged valve body gasket.
• Restricted apply passage.
If the problem found, replaces necessary.

W as the problem found? — Go to
Step 8 Go to Step 6
6 Check the DTC on a scan tool.

Is DTC found on a scan tool? — Go to
Step 7 Go to Step 8
7 Replace the valve body. (Refer to Section 7A4).

Is the action complete? — Go to
Step 8 —

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ISUZU KB P190 2007

7A2-94 TRANSMISSION CONTROL SYSTEM (AW30–40LE)


Condition For Setting The DTC
The TCM detects following conditions for 0.5 seconds
continuously at shifting.
• Voltage at connector pin is 0V when solenoid is “ON”.
(DTC P0973)
• Voltage at connector pin is ignition voltage when
solenoid is “OFF”. (DTC P0974)
Action Taken When The DTC Sets
• No L-up control.
• No line pressure reduction control at gear change.
• No torque reduction control.
• No squat control.
• No slope control.
• No line pressure reduction control at garage.
• No input revolution sensor failure detection.
• No shift solenoid failure detection.
• No L-up solenoid failure detection.
• Change to emergency mode.
• 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.
• 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 P0973 or P0974

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. Start the engine.
3. Depress the brake pedal and place the select lever in D position.
4. Press the 3rd start switch. (Turn the 3rd start switch “ON”.)
5. Press the 3rd start switch again. (Turn the 3rd start switch “OFF”.)

Does a scan tool indicate DTC P0973 or P0974? — Go to
Step 3 Refer to
Diagnostic Aids
3 1. Turn “ON” the ignition with the engine “ON”.
2. Place the selector lever in the “P” position.
3. Measure the voltage between terminal C94-16 and terminal C94-1 (GND) on the TCM pigtail
connector by 5-8840-0285-0 DMM.

Is the voltage specified value? 8∼16V Go to
Step 4 Go to Step 10

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ISUZU KB P190 2007

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

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ISUZU KB P190 2007

7A2-98 TRANSMISSION CONTROL SYSTEM (AW30–40LE)

Condition For Setting The DTC
The TCM detects following conditions for 0.5 seconds
continuously at shifting.
• Voltage at connector pin is 0V when solenoid is “ON”.
(DTC P0976)
• Voltage at connector pin is ignition voltage when
solenoid is “OFF”. (DTC P0977)
Action Taken When The DTC Sets
• No L-up control.
• No line pressure reduction control at gear change.
• No torque reduction control.
• No squat control.
• No slope control (keep mode).
• No line pressure reduction control at garage.
• No input revolution sensor failure detection.
• No shift solenoid failure detection.
• No L-up solenoid failure detection.
• Change to emergency mode.
• 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.
• 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 P0976 or P0977

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. Start the engine.
3. Depress the brake pedal and place the select lever in D position.
4. Press the 3rd start switch. (Turn the 3rd start switch “ON”.)
5. Press the 3rd start switch again. (Turn the 3rd start switch “OFF”.)

Does a scan tool indicate DTC P0976 or P0977? — Go to
Step 3 Refer to
Diagnostic Aids
3 1. Turn “ON” the ignition with the engine “ON”.
2. Place the selector lever in the “P” position.
3. Measure the voltage between terminal C94-15 and terminal C94-1 on the TCM pigtail connector by 5-
8840-0285-0 DMM.

Is the voltage specified value? 8∼16V Go to
Step 4 Go to Step 5

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ISUZU KB P190 2007

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


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ISUZU KB P190 2007

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


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ISUZU KB P190 2007

7A2-106 TRANSMISSION CONTROL SYSTEM (AW30–40LE)

(4) All of the following conditions are met.
• Device Control is not operating.
• Disable Normal Communication is receiving enable.
• DTC Clear is not operating.
Condition For Setting The DTC
The TCM detects following conditions for 0.5 seconds
continuously at shifting.
• Voltage at connector pin is 0V when solenoid is “ON”.
(DTC P2769)
• Voltage at connector pin is ignition voltage when
solenoid is “OFF”. (DTC P2770)
Action Taken When The DTC Sets
• No L-up solenoid functional failure detection.
• No squat control. (DTC P2770)
• The TCM fixes to 1st gear when the vehicle speed is less than 10 km/h (6 mph).
• 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.5 (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 P2769 or P2770

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. Start the engine.
3. Drive the vehicle in D position.
4. Accelerate the vehicle until the gear position
becomes the 4th.
5. Release the accelerator pedal and accelerate the vehicle until the gear position becomes the 4th
again.

Does a scan tool indicate DTC P2769 or P2770? — Go to
Step 3 Refer to
Diagnostic Aids

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ISUZU KB P190 2007