2007 ISUZU KB P190 air condition

7A2-42 TRANSMISSION CONTROL SYSTEM (JR405E)
111. Test the signal circuit between the TCM (pin 4
of C-95) and the in-line harness connector (pin
2 of E-54) for an open circuit or high
resistance.
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 18 Go to Step 15
12 1. Test the low reference circuit between the
TCM (pin 14 of C-95) and the in-line harness
connector (pin 8 of E-54) for an open circuit or
high resistance.
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 18 Go to Step 15
13 1. Inspect for an intermittent and for poor
connections at the in-line harness connector
(pins 2 and 8 of E-54).
2. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 18 Go to Step 14
14 1. Remove the transmission oil pan. Refer to
repair instructions (On-Vehicle Service).
2. Test the signal circuit between the TFT sensor and the in-line harness connector (pin 2 of E-
54) for the following conditions:
• An open circuit
• A short to ground
• A short to the low reference circuit
• A short to the solenoid valve circuit
• High resistance
3. Test the low reference circuit between the TFT sensor and the in-line harness connector (pin
8 of E-54) for an open circuit or high
resistance.
4. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 18 Go to Step 16
15 1. Turn OFF the ignition.
2. Disconnect the TCM harness connector.
3. Inspect for an intermittent and for poor connections at the harness connector of the
TCM (pins 4 and 14 of C-95).
4. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 18 Go to Step 17
16 Replace the TFT sensor. Refer to repair
instructions (On-Vehicle Service). (TFT sensor is
part of the harness assembly)
Did you complete the replacement? —
Go to Step 18 —
17 Important:
Replacement TCM must be
programmed.
Replace the TCM. Refer to TCM Replacement.
Did you complete the replacement? —
Go to Step 18 —
Step
Action Value(s)Yes No

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ISUZU KB P190 2007

TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-45
4Intermittently jump the signal circuit (pin 1 of E-31)
with a test lamp that is connected to a known good
ground while observing the AT Input Speed
parameter with a scan tool.
Does the scan tool indicate any AT input speed
when the circuit is intermittently pulled to ground? —
Go to Step 5 Go to Step 8
5 Connect a test lamp between the ignition voltage
feed circuit and the low reference circuit (pins 2 and
3 of E-31).
Does the test lamp illuminate? —
Go to Step 9 Go to Step 7
6 Repair the open circuit or high resistance between
the Back Up (15A) fuse and the ISS sensor (pin 2
of E-31). Check the Back Up (15A) fuse first.
Did you complete the repair? —
Go to Step 14 —
7 Repair the open circuit or high resistance on the
low reference circuit between the ISS sensor (pin 3
of E-31) and the engine ground terminal (E-10).
Clean or tighten ground as necessary.
Did you complete the repair? —
Go to Step 14 —
8 1. Test the signal circuit between the TCM (pin 3
of C-95) and the ISS sensor (pin 1 of E-31) for
the following conditions
• An open circuit
• A short to ground
• A short to the low reference
• A short to battery or ignition voltage
• High resistance
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 14 Go to Step 10
9 1. Inspect for an intermittent and for poor
connections at the harness connector of the
ISS sensor (pin 1, 2 and 3 of E-31).
2. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 14 Go to Step 11
10 1. Turn OFF the ignition.
2. Disconnect the TCM harness connector.
3. Inspect for an intermittent and for a poor connection at the harness connector of the
TCM (pin 3 of C-95).
4. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 14 Go to Step 13
Step
Action Value(s)Yes No

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ISUZU KB P190 2007

7A2-46 TRANSMISSION CONTROL SYSTEM (JR405E)
111. Inspect the ISS sensor and the reverse & high
clutch drum for the following conditions:
• Physical damage of sensor
• Loose or improper installation of sensor
• Excessive air gap
• Foreign material passing between sensor and reverse & high clutch drum
• Physical damage of reverse & high clutch drum
2. Repair or replace as necessary.
Did you find and correct the condition? —
Go to Step 14 Go to Step 12
12 Replace the ISS sensor. Refer to repair instructions
(On-Vehicle Service).
Did you complete the replacement? —
Go to Step 14 —
13 Important:
Replacement TCM must be
programmed.
Replace the TCM. Refer to TCM Replacement.
Did you complete the replacement? —
Go to Step 14 —
14 1. Reconnect all previously disconnected fuse,
components or harness connector(s).
2. Clear the DTCs with a scan tool.
3. Turn OFF the ignition for 30 seconds.
4. Start the engine.
5. Operate the vehicle within the Conditions for Running the DTC.
Did the DTC fail this ignition? —
Go to Step 3 Go to Step 15
15 Observe the DTC Information with a scan tool.
Are there any DTCs that you have not diagnosed? —
Go to DTC List System OK
Step
Action Value(s)Yes No

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ISUZU KB P190 2007

7A2-48 TRANSMISSION CONTROL SYSTEM (JR405E)
4Intermittently jump the signal circuit (pin 1 of E-30)
with a test lamp that is connected to a known good
ground while observing the AT Output Speed or
Vehicle Speed parameter with a scan tool.
Does the scan tool indicate any AT output speed or
vehicle speed when the circuit is intermittently
pulled to ground? —
Go to Step 5 Go to Step 8
5 Connect a test lamp between the ignition voltage
feed circuit and the low reference circuit (pins 2 and
3 of E-30).
Does the test lamp illuminate? —
Go to Step 9 Go to Step 7
6 Repair the open circuit or high resistance between
the TCM (15A) fuse and the OSS sensor (pin 2 of
E-30).
Did you complete the repair? —
Go to Step 14 —
7 Repair the open circuit or high resistance on the
low reference circuit between the OSS sensor (pin
3 of E-30) and the engine ground terminal (E-10).
Clean or tighten ground as necessary.
Did you complete the repair? —
Go to Step 14 —
8 1. Test the signal circuit between the TCM (pin
13 of C-95) and the OSS sensor (pin 1 of E-
30) for the following conditions:
• An open circuit
• A short to ground
• A short to the low reference
• A short to battery or ignition voltage
• High resistance
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 14 Go to Step 10
9 1. Inspect for an intermittent and for poor
connections at the harness connector of the
OSS sensor (pin 1, 2 and 3 of E-30).
2. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 14 Go to Step 11
10 1. Turn OFF the ignition.
2. Disconnect the TCM harness connector.
3. Inspect for an intermittent and for a poor connection at the harness connector of the
TCM (pin 13 of C-95).
4. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 14 Go to Step 13
Step
Action Value(s)Yes No

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ISUZU KB P190 2007

TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-49
111. Inspect the OSS sensor and the parking gear
for the following conditions:
• Physical damage of sensor
• Loose or improper installation of sensor
• Excessive air gap
• Foreign material passing between sensor and parking gear
• Physical damage of parking gear
2. Repair or replace as necessary.
Did you find and correct the condition? —
Go to Step 14 Go to Step 12
12 Replace the OSS sensor. Refer to repair
instructions (On-Vehicle Service).
Did you complete the replacement? —
Go to Step 14 —
13 Important:
Replacement TCM must be
programmed.
Replace the TCM. Refer to TCM Replacement.
Did you complete the replacement? —
Go to Step 14 —
14 1. Reconnect all previously disconnected
components or harness connector(s).
2. Clear the DTCs with a scan tool.
3. Turn OFF the ignition for 30 seconds.
4. Drive the vehicle while observing the Vehicle Speed parameter with a scan tool.
Does the scan tool indicate correct vehicle speed? —
Go to Step 15 Go to Step 3
15 Observe the DTC Information with a scan tool.
Are there any DTCs that you have not diagnosed? —
Go to DTC List System OK
Step
Action Value(s)Yes No

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ISUZU KB P190 2007

TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-51
51. Test the signal circuit between the ECM (33 of
C-58) and the TCM (7 of C-94) for the
following conditions:
• An open circuit
• A short to ground
• A short to battery or ignition voltage
• High resistance
2. Repair the circuit(s) as necessary.
Did you find and correct the condition? —
Go to Step 10 Go to Step 6
6 1. Turn OFF the ignition.
2. Inspect for an intermittent and for a poor connection at the harness connector of the
TCM (pin 7 of C-94).
3. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 10 Go to Step 8
7 1. Turn OFF the ignition.
2. Inspect for an intermittent and for a poor connection at the harness connector of the
ECM (pin 33 of C-58).
3. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 10 Go to Step 9
8 Important:
Replacement TCM must be
programmed.
Replace the TCM. Refer to TCM Replacement.
Did you complete the replacement? —
Go to Step 10 —
9 Important:
Replacement ECM must be
programmed and learned.
Replace the ECM. Refer to ECM Replacement.
Did you complete the replacement? —
Go to Step 10 —
10 1. Reconnect all previously disconnected
harness connector(s).
2. Clear the DTCs with a scan tool.
3. Turn OFF the ignition for 30 seconds.
4. Start the engine.
5. Observe the Engine Speed parameter with a scan tool.
Does the scan tool indicate correct engine speed? —
Go to Step 11 Go to Step 4
11 Observe the DTC Information with a scan tool.
Are there any DTCs that you have not diagnosed? —
Go to DTC List System OK
Step
Action Value(s)Yes No

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ISUZU KB P190 2007

7A2-52 TRANSMISSION CONTROL SYSTEM (JR405E)
DTC P0731, P0732, P0733 or P0734 (Flash Code 41, 42, 43 or 44)
Circuit Description
The TCM calculates the gear ratio based on the input
shaft speed signal from the input shaft speed (ISS)
sensor and the output speed signal from the output
shaft speed (OSS) sensor. The TCM compares the
known transmission gear ratio to the calculated ratio for
the selected gear ranges. If the TCM detects an
unknown transmission gear ratio two consecutive
driving cycles, this DTC will set.
Condition for Running the DTC • Other than DTCs P0731, P0732, P0733 and P0734 are not set.
• The ignition switch is ON.
• The transmission fluid temperature is more than 60 °C (140 °F).
• The input shaft speed is more than 1000 RPM.
• The vehicle speed is more than 10 km/h (6 MPH).
• The selector lever is forward range for longer than 2 seconds.
• The TCM is not under gearshift control.
Condition for Setting the DTC • The TCM detects that the output shaft speed is more than 500 RPM over the calculated speed
(based on the input shaft speed and the gear ratio)
for 7 seconds after each gearshift has completed.
Action Taken When the DTC Sets • The TCM blinks the Check Trans lamp on the second consecutive driving cycle when the
diagnostic runs and fails.
Condition for Clearing the DTC • The TCM turns OFF the Check Trans lamp when the diagnostic runs and does not fail. • A current DTC clears when the diagnostic runs and
does not fail.
Diagnostic Aids • If an intermittent condition is suspected, refer to Intermittent Conditions in this section.
• Electromagnetic interference in the ISS sensor or OSS sensor circuits may set this DTC.
• An intermittent ISS sensor or OSS sensor signal pulse may set this DTC.
• Ensure the ISS sensor and OSS sensor is tight.
• Use the Clutch, Brake, Solenoid and Pressure Switch Logic table to verify each component works
properly within the selected gear range.
• A transmission mechanical problem will cause this DTC to set.
• Sticking or contamination of shift valves may cause intermittent incorrect gear ratios.
• If multiple incorrect gear ratio codes are set, problem in fluid pressure, low ATF level, plugged
filter or oil pump problem may exist.
Notice: • Each DTC agrees with the following gear positions.
- P0731: 1st gear
- P0732: 2nd gear
- P0733: 3rd gear
- P0734: 4th gear
Schematic Reference: Transmission Controls
Schematics
Connector End View Reference: Transmission
Controls Connector End Views or TCM Connector End
Views
Circuit/ System Testing DTC P0731, P0732, P0733 or P0734
Step Action Value(s)Yes No
1 Did you perform the Diagnostic System Check -
Transmission Controls? —
Go to Step 2 Go to Diagnostic
System Check - Transmission Controls
2 Perform the ATF level check. Refer to repair
instructions (On-Vehicle Service).
Did you perform the ATF level check? —
Go to Step 3 Go to Transmission
Fluid Checking Procedure
3 1. Install a scan tool.
2. Turn OFF the ignition for 30 seconds.
3. Drive the vehicle while observing the DTC Information with a scan tool.
Is there any DTCs set other than P0731, P0732,
P0733 or P0734? —
Refer to Applicable DTC Go to Step 4

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ISUZU KB P190 2007

TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-53
41. Inspect all of the circuits going to the input
shaft speed (ISS) sensor and the output shaft
speed (OSS) sensor for the following
conditions:
• Routed too closely to fuel injection wiring or components
• Routed too closely to after-market add- on electrical equipment
• Routed too closely to solenoids and relays
2. If you find incorrect routing, correct the harness routing.
Did you find and correct the condition? —
Go to Step 13 Go to Step 5
5 1. Disconnect the ISS sensor and the OSS
sensor harness connector.
2. Inspect for an intermittent, for poor connections and corrosion at the harness
connector of the ISS sensor (pins 1, 2 and 3 of
E-31) and the OSS sensor (pins 1,2 and 3 of
E-30).
3. Disconnect the TCM harness connector.
4. Inspect for an intermittent, for poor connections and corrosion at the harness
connector of the TCM (pins 3 and 13 of C-95).
5. Repair the connection(s) as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 6
6 1. Inspect the ISS sensor and the OSS sensor
for the following conditions:
• Physical damage of sensor
• Loose or improper installation of sensor
• Excessive air gap
• Foreign material passing between ISS sensor and reverse & high clutch drum
• Foreign material passing between OSS sensor and parking gear
• Physical damage of reverse & high clutch drum or parking gear
2. Repair or replace as necessary.
Did you find and correct the condition? —
Go to Step 13 Go to Step 7
7 1. Place the selector lever in D range.
2. Observe the Low & Reverse Brake Pressure Switch, 2-4 Brake Pressure Switch and High
Clutch Pressure Switch parameter with a scan
tool. Refer to Clutch, Brake, Solenoid and
Pressure Switch Logic table.
Does the each transmission fluid pressure (TFP)
switch display match each selected gear range? —
Go to Step 8 Refer to DTC
P1853, P1858 or P1863
8 Perform the line pressure test. Refer to Line
Pressure Test.
Is the line pressure within specifications for each
selected gear range? —
Go to Step 9 Refer to appropriate
instructions in the
Line Pressure Test
Step
Action Value(s)Yes No

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ISUZU KB P190 2007