sensor ISUZU KB P190 2007 Workshop Repair Manual

TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-111
D2: Gearshift Frequently
Diagnosis Hints• When inspecting faulty gear shifting, it is important to distinguish between
the fault of the electric system and transmission main unit.
• Fault of electric system. - Monitor the output signal (each solenoid driving signal) using a scan tool. If a trouble signal is sent to the solenoid synchronously with the faulty
gear shifting, the fault is originated in the electric system.
- Monitor the input signal (signal from each sensor) using a scan tool and find an input signal which has an output signal (each solenoid driving
signal) subjected to a fault.
- Fault of the electric system may be derived from temperature or vibration. For instance, although the engine is normal while it is cold, fault may
occur when the engine is warmed up or the vehicle is running.
• Fault of mechanical system. - If the gear is incorrectly shifted, irrespective of the operating signal (On/ Off) of each solenoid, the fault is originated from the transmission main
unit.
- If the clutch slips, or the transmission fluid smells burnt or is contaminated or black, or the stall speed increases. Gear ratio error DTC might be set.
Transmission Range Switch & Selector
Lever Cable Checks Inspect the transmission range switch and selector lever cable for misadjusting
or disordering. Refer to On-Vehicle Service section.
Transmission Fluid Checks Inspect the transmission fluid for the following conditions. If the transmission fluid
is extremely blacked, contaminated or smells burnt, slipping of clutch is
suspected.
• Low quantity
• Contamination
•Smell
Line Pressure Checks Inspect the line pressure in forward ranges for a possible dropped pressure.
Refer to Line Pressure Test in Test Instruction section.
Stall Speed Checks Inspect the stall speed in forward ranges. Refer to Stall Test in Test Instruction
section.
Control Valve Body Checks Inspect the valve body for the following conditions.
• Faulty operation
• Sticking spool valve
• Sticking shift solenoid valve. Perform function check. Refer to On-Vehicle Service section.
• Faulty operation of transmission fluid pressure switch. Perform function check. Refer to On-Vehicle Service section.
• Clogged hydraulic circuit
Checks
Action
Checks Action
Definition:
Shift down or engine overrun occurs above than kick-down area.
Diagnosis Hints The same causes as in category No. “C1 - C8: Engine Race Up (Slipping)” are
suspected.

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ISUZU KB P190 2007

7A2-112 TRANSMISSION CONTROL SYSTEM (JR405E)
D3: Gearshift Point is Low or High at All Points
D4: Gearshift Point is Low or High at Limited Area
D5: No Kick-down
E1: No Gearshift
Checks Action
Definition: • Gearshift point is deviated from the shift speed chart.
• Gear is not shifted up properly, even though the vehicle is accelerating.
• Gear is not shifted immediately and enough acceleration cannot be obtained, even though the accelerator pedal is being stepped on.
Diagnosis Hints • Inspect the output shaft speed (OSS) sensor for faulty operation.
• Incorrect accelerator pedal position signal is suspected. Observe the Accelerator Pedal Position (APP). APP parameter should change linearly
from 0 to 99 or 100% according to the accelerator pedal operation.
Checks Action
Definition:
The engine speeds up but the vehicle speed does not increase when the accelerator pedal is being stepped on at starting.
Diagnosis Hints Incorrect accelerator pedal position signal is suspected. Observe the
Accelerator Pedal Position (APP). APP parameter should change linearly from
0 to 99 or 100% according to the accelerator pedal operation.
Checks Action
Definition: • Gear is fixed, such as no gearshift from 1st to 2nd, 2nd to 3rd, and 3rd to 4th.
• Sometimes the gear is shifted, and sometimes it is not possible.
Diagnosis Hints • Fixing at same gear speed, a signal error from the accelerator pedal
position (APP) sensor or trouble in the transmission main unit are
suspected.
• Slipping of the clutch is suspected. Gear ratio error DTC might be set.
Transmission Range Switch & Selector Lever
Cable Checks Inspect the transmission range switch and selector lever cable for misadjusting
or disordering. Refer to On-Vehicle Service section.
Transmission Fluid Checks Inspect the transmission fluid for the following conditions. If the transmission
fluid is extremely blacked, contaminated or smells burnt, slipping of clutch is
suspected.
• Low quantity
• Contamination
•Smell
Line Pressure Checks Inspect the line pressure in forward ranges for a possible dropped pressure.
Refer to Line Pressure Test in Test Instruction section.
Stall Speed Checks Inspect the stall speed in forward ranges. Refer to Stall Test in Test Instruction
section.
Control Valve Body Checks Inspect the valve body for the following conditions.
• Faulty operation
• Sticking spool valve
• Sticking shift solenoid valve. Perform function check. Refer to On-Vehicle Service section.
• Clogged hydraulic circuit
Clutch and Brake Checks Inspect the low clutch, high clutch or low & reverse brake for slipping.

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ISUZU KB P190 2007

TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-113
E2: Only 4th Gear is Not Selectable
E3: Gear is Changed from 2nd to 3rd in 2 Range
E4: Gear is Changed from 1st to 2nd in L Range
E5: Gear is Changed from 3rd to 4th in 3 Range
Sensor Checks Inspect the input shaft speed (ISS) sensor and output shaft speed (OSS)
sensor for faulty operation.
Additional Checks • Inspect the TCM grounds for being clean, tight, and in their proper
locations.
• Observe the Accelerator Pedal Position (APP). APP parameter should change linearly from 0 to 99 or 100% according to the accelerator pedal
operation.
Checks
Action
Checks Action
Definition:
Gearshift is not possible from 3rd to 4th even though the vehicle is accelerating.
Diagnosis Hints When the transmission fluid temperature is lower than 10 °C (50 °F), gearshift
from the 3rd to the 4th is inhibited.
Transmission Range Switch & Selector Lever
Cable Checks Inspect the transmission range switch and selector lever cable for misadjusting
or disordering. Refer to On-Vehicle Service section.
Transmission Fluid Checks Inspect the transmission fluid for the following conditions. If the transmission
fluid is extremely blacked, contaminated or smells burnt, slipping of clutch is
suspected.
• Low quantity
• Contamination
•Smell
Line Pressure Checks Inspect the line pressure in forward ranges for a possible dropped pressure.
Refer to Line Pressure Test in Test Instruction section.
Stall Speed Checks Inspect the stall speed in forward ranges. Refer to Stall Test in Test Instruction
section.
Control Valve Body Checks Inspect the valve body for the following conditions.
• Faulty operation
• Sticking spool valve
• Sticking shift solenoid valve. Perform function check. Refer to On-Vehicle Service section.
• Clogged hydraulic circuit
Clutch and Brake Checks Inspect the low clutch for seizing.
Sensor Checks Inspect the transmission fluid temperature (TFT) sensor. Use the Temperature
vs. Resistance table to test the TFT sensor at various temperature levels to
evaluate the possibility of a skewed sensor.
Checks Action
Definition: • Gear is shifted from 2nd to 3rd in 2 range.
• Gear is shifted from 1st to 2nd in L range.
• Gear is shifted from 3rd to 4th in 3 range.
Transmission Range Switch & Selector Lever
Cable Checks Inspect the transmission range switch and selector lever cable for misadjusting
or disordering. Refer to On-Vehicle Service section.

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TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-115
F3: Noise or Vibration Occurs During in R, D, 3, 2 or L Range
F4: Engine Brake Does Not Apply in L Range
F5: Engine Stalls Before Vehicle Stops from Running
G1: Vehicle Moves in P Range or Parking is Not Disengaged in Other Than P Range
Diagnosis Hints The same causes as in category No. “C1 - C8: Engine Race Up (Slipping)”
are suspected. When the condition of No. C1 - C8 grows worse, No. F2
results.
Checks Action
Definition:
Noise or vibration occurs in the vicinity of the transmission during running.
Diagnosis Hints Cause other than transmission is suspected. Reproduce the running
condition using a lift up, chassis dynamo, etc. to investigate the origin of the
noise and vibration.
Additional Checks • Inspect the differential gear noise.
• Inspect the propeller shaft noise.
• Inspect the tires for unbalanced or poor uniformity.
Checks
Action
Checks Action
Definition:
The engine brake does not apply, allowing the vehicle to run freely when the accelerator pedal is released at low speed in L
range.
Diagnosis Hints • Slipping of the clutch is suspected. Gear ratio error DTC might be set.
Line Pressure Checks Inspect the line pressure in forward ranges for a possible dropped pressure.
Refer to Line Pressure Test in Test Instruction section.
Control Valve Body Checks Inspect the valve body for the following conditions.
• Faulty operation
• Sticking spool valve
• Sticking shift solenoid valve. Perform function check. Refer to On- Vehicle Service section.
• Clogged hydraulic circuit
Clutch and Brake Checks Inspect the low & reverse brake for slipping.
Sensor Checks Inspect the input shaft speed (ISS) sensor and output shaft speed (OSS)
sensor for faulty operation.
Checks Action
Definition:
The engine stalls simultaneously with the vehicle when the brake pedal is stepped on to stop the vehicle during running.
Diagnosis Hints The same causes as in category No. “B5: Engine Stalls When Selector Lever
is Changed from N to R, D, 3, 2 or L Range” is suspected.
Checks Action
Definition:
Vehicle moves even though it stops on a slope and P range is selected.
Vehicle does not move even though a position other than P range is selected, and the accelerator pedal is being stepped on.
Diagnosis Hints If the vehicle moves in N range, refer to category No. “B1: Vehicle Runs in
N Range”.

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TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-117
H1: Judder Occurs at Lock Up
H2: Large Shock at Lock Up
H3: Lock Up Point is High or Low
I1: No Lock Up
Diagnosis Hints • Causes such as the solenoid operating sound or a faulty oil pump are
suspected.
• Distinguishing is possible by stopping the solenoid operation temporarily, checking the correlation for the former case and, changing
the line pressure and confirming the correlation with noise.
• As a matter of course, noise other than the transmission may be generated around the engine, and should be checked carefully.
Notice: When the noise is generated only at the time of a gear shift, it may
be the sound of transmission fluid flowing or gear noise. If the sound varies
depending on the gear speed to be shifted, it may be the gear noise
generated from the planetary gear and its components. If the sound varies
depending on the vehicle speed, it may be the gear noise of the output
system, or the gear noise of the input system or a faulty torque converter.
Checks
Action
Checks Action
Definition:
Judder occurs when lock up area.
Diagnosis Hints Slip due to burning of the torque converter clutch (TCC) facing or insufficient
engagement due to dropped working pressure are suspected. Refer to
category No. “l1: No Lock Up “.
Notice: When the TCC facing has burnt, foreign material mixed in the oil
cooler is suspected. In such a case, inspect the oil cooler circuit for clogging
of the oil cooler.
Checks Action
Definition: • A large shock is felt at lock up.
• Lock up point is excessively high or low.
Diagnosis Hints Incorrect input signals or faulty operation of torque converter clutch (TCC) is
suspected. Refer to category No. “I1: No Lock Up”.
Checks Action
Definition:
Lock up is not performed even though lock up control conditions being satisfied.
Diagnosis Hints • Monitor the signal to the torque converter clutch (TCC) solenoid valve
while carrying out a running test.
• When the transmission fluid temperature is lower than 20 °C (68 °F),
lock up control is inhibited.
• When the output signal to the TCC solenoid valve is sent correctly, causing no lock up, clogged hydraulic circuits or malfunction of the TCC
piston may be suspected.
• Even with the lock up area, the output signal to the TCC solenoid valve is not sent, a fault of the transmission fluid temperature (TFT) sensor
controlling the lock up may be suspected.
Notice: When the TCC facing has burnt, foreign material mixed in the oil
cooler is suspected. In such a case, inspect the oil cooler circuit for clogging
of the oil cooler.

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ISUZU KB P190 2007

7A2-118 TRANSMISSION CONTROL SYSTEM (JR405E)
J1: Transmission Fluid Leaks from Breather
J2: Transmission Fluid Leaks Between Engine and Converter Housing
J3: Transmission Fluid Leaks Between Converter Housing and Transmission Case
J4: Transmission Fluid Leaks Between Transmission Case and Extension Housing
J3: Transmission Fluid Leaks from Oil Pan
J3: Transmission Fluid Leaks from Manual Shaft Oil Seal
J3: Transmission Fluid Leaks from Oil Cooler Pipe Joint
Z1: Transmission Overheat
Transmission Fluid Checks Inspect the transmission fluid for the following conditions. If the transmission
fluid is extremely blacked, contaminated or smells burnt, slipping of clutch is
suspected.
• Low quantity
• Contamination
• Smell
Control Valve Body Checks Inspect the valve body for the following conditions.
• Faulty operation
• Sticking spool valve
• Sticking TCC solenoid valve. Perform function check. Refer to On- Vehicle Service section.
• Clogged hydraulic circuit
Sensor Checks Inspect the TFT sensor. Use the Temperature vs. Resistance table to test
the TFT sensor at various temperature levels to evaluate the possibility of a
skewed sensor.
Checks
Action
Checks Action
Definition:
Transmission fluid leaks from breather.
Diagnosis Hints Transmission fluid quantity is excessively high.
Checks Action
Definition:
Transmission fluid leaks between engine and converter housing.
Transmission fluid leaks between converter housing and transmission case.
Transmission fluid leaks between transmission case and extension housing.
Transmission fluid leaks from oil pan.
Transmission fluid leaks from manual shaft oil seal.
Transmission fluid leaks from oil cooler pipe joint.
Diagnosis Hints Faulty oil seal or contact surface is suspected.
Checks Action
Definition:
Smells burnt or smoke from transmission.
Diagnosis Hints • Transmission fluid quantity is excessively high.
• Slipping of the clutch is suspected. Gear ratio error DTC might be set.
• Clogged oil cooler.
• Faulty operation of oil pump.
• Faulty torque converter clutch (TCC) piston.

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TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-119
Z2: Mode Lamp (Power Drive or 3rd Start) Does Not Turn On
Z3: Mode Lamp (Power Drive or 3rd Start) Does Not Turn Off
Z4: A/T Oil Temperature Lamp Turns On
Z5: Selector Lever Feeling is Faulty
Z6: Poor Fuel Consumption
Checks Action
Definition:
Mode lamp on the instrument panel (IP) cluster does not turn ON even though the switch is ON.
Diagnosis Hints • Faulty mode switch circuit.
• Faulty mode switch.
• Faulty lamp control circuit.
• Faulty IP cluster.
Checks Action
Definition:
Mode lamp on the instrument panel cluster does not turn OFF even though the switch is OFF.
Diagnosis Hints • Faulty mode switch circuit.
• Faulty mode switch.
• Faulty lamp control circuit.
• Faulty IP cluster.
Checks Action
Definition:
A/T oil temperature lamp turns On sometimes.
Diagnosis Hints • If the fluid temperature increases to 135°C (275 °F), the TCM illuminates
A/T Oil Temp lamp on the instrument panel cluster. When the fluid
temperature deceases below 125 °C (257 °F), the lamp goes off.
• When the vehicle is stuck in the mud or continues to accelerate under overload, transmission fluid temperature increases and lamp may be
turned On.
• If the lamp is On under usual conditions, following causes are suspected. - Transmission fluid level has increased for some fault. Refer to category No. “Z1: Transmission Overheat”.
- Skewed transmission fluid temperature (TFT) sensor.
Checks Action
Definition:
Selector lever feeling is faulty.
Diagnosis Hints • Inspect the selector lever cable for misadjusting or disordering.
• Faulty manual plate.
Checks Action
Definition:
Poor fuel consumption.
Diagnosis Hints The same causes as in category No. “C1 - C8: Engine Race Up (Slipping)” are
suspected.

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ISUZU KB P190 2007

7A2-122 TRANSMISSION CONTROL SYSTEM (JR405E)
Standard Value
Diagnosis 1. If the line pressure is lower than the standard value at idle in all ranges.
• Abraded oil pump.
• Faulty operation of each solenoid valve.
• Sticking of pressure regulator spool valve or pilot spool valve.
• Fatigued pressure regulator spool valve spring or pilot spool valve spring.
• Transmission fluid leaking from the oil strainer, oil pump, pressure regulator spool valve, torque
converter relief spool valve or pressure relief valve.
2. If the line pressure is lower than the standard value at idle in D, 3, 2 and L range.
• Transmission fluid leaking from the low clutch hydraulic circuit.
3. If the line pressure is lower than the standard value at idle in R range.
• Transmission fluid leaking from the reverse clutch hydraulic circuit.
• Transmission fluid leaking from the low & reverse brake hydraulic circuit.
4. If the line pressure is lower that the standard value at idle in L or R range.
• Transmission fluid leaking from the low & reverse brake hydraulic circuit.
5. If the line pressure is higher than the standard value at idle in all ranges.
• Faulty accelerator pedal position signal.
• Faulty transmission fluid temperature (TFT) sensor.
• Faulty operation of low clutch solenoid valve.
• Sticking pilot spool valve.
• Sticking pressure regulator spool valve or plug.
6. If the line pressure is lower than the standard value at stall speed in all ranges.
• Faulty accelerator pedal position signal.
• Faulty operation of pressure control (PC) solenoid valve.
• Faulty operation of low clutch solenoid valve.
• Sticking pilot spool valve.
• Sticking pressure regulator spool valve or plug.
Selector lever position Engine
speed Line pressure (kPa/ psi)
D, 3, 2 or D Idle 350 - 480 / 51 - 70
R Stall 1050 - 1250 / 152 - 182
Idle 450 - 650 / 65 - 95
Stall 1400 - 1630 / 203 - 237

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TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-135
22 of C-94 —Not used— — ——
23 of C-94 — Not used— — ——
24 of C-94 GRN/ YEL Power drive switch
signal 24 of C-94
(back probe) GroundSwitch is OFF Nearly 12 volts
Switch is ON Less than 2 volts
1 of C-95 RED/ YEL 2-4 brake TFP switch
signal 1 of C-95
(back probe) Ground2nd or 4th gear Less than 2 volts
Other than 2nd or 4th gear Nearly 12 volts
2 of C-95 PNK/ BLK 2 range switch signal 2 of C-95 Ground 2 range
Nearly 12 volts
Other than 2 range Less than 2 volts
3 of C-95 BRN/ RED ISS sensor signal 3 of C-95
(back probe) 5 of C-95
(back
probe) Vehicle run at 20 km/h
(12 MPH) in L range with 1st gear Nearly 6.5 volts by
AC range or waveform
4 of C-95 BLU TFT sensor signal 4 of C-95 14 of C-
95 Ignition OFF Refer to
Temperature vs.
Resistance table
5 of C-95 BLK Ground5 of C-95 Ground Ignition OFF Continuity
6 of C-95 BLU/ BLK Low & reverse brake
solenoid control 6 of C-95
(back probe) 22 of C-
95 (back
probe) P or N range
Nearly 6.2 volts by
AC range or
waveform
7 of C-95 BLK/ YEL 2 & 4 brake solenoid
control 7 of C-95
(back probe) 22 of C-
95 (back
probe) P or N range
Nearly 6.2 volts by
AC range or
waveform
8 of C-95 RED High clutch solenoid
control 8 of C-95
(back probe) 22 of C-
95 (back
probe) P or N range
Nearly 6.2 volts by
AC range or
waveform
9 of C-95 WHT/ BLU Low clutch solenoid
control 9 of C-95
(back probe) 22 of C-
95 (back
probe) D range with 4th gear
Nearly 6.2 volts by
AC range or
waveform
10 of C-95 RED/ BLK N range switch signal 10 of C-95 Ground 2 range
Nearly 12 volts
Other than 2 range Less than 2 volts
11 of C-95 BLU D range switch signal 11 of C-95 Ground D range
Nearly 12 volts
Other than 2 range Less than 2 volts
12 of C-95 YEL Low & reverse brake
TFP switch 12 of C-95
(back probe) GroundR range or L range Less than 2 volts
Other than R range or L range Nearly 12 volts
13 of C-95 YEL/ RED OSS sensor signal 13 of C-95
(back probe) 5 of C-95
(back
probe) Vehicle run at 20 km/h
(12 MPH) in L range with 1st gear Nearly 6.8 volts by
AC range or waveform
14 of C-95 BLU/ BLK TFT sensor low
reference 4 of C-9514 of C-
95 Ignition OFF Refer to
Temperature vs.
Resistance table
15 of C-95 — Not used— — ——
16 of C-95 — Not used— — ——
17 of C-95 BLK TCC solenoid control 17 of C-95
(back probe) 5 of C-95
(back
probe) TCC is commanded
OFF Waveform
TCC is commanded ON Waveform
18 of C-95 WHT Ignition voltage 18 of C-95 Ground Ignition switch ON Nearly 12 volts Pin No. Wire color Pin function DMM (+) DMM (-) Test condition Standard value

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TRANSMISSION CONTROL SYSTEM (JR405E) 7A2-137
Input shaft speed (ISS) sensor signal• Measurement terminal: 3 of C-95 (+) & 5 of C-95 (- )
• Measurement scale: 5 volts/div & 500 micro sec./ div
• Measurement condition: Vehicle run at 20 km/h (12 MPH) in L range with 1st gear
Output shaft speed (OSS) sensor signal
• Measurement terminal: 13 of C-95 (+) & 5 of C-95 (-)
• Measurement scale: 5 volts/div & 5 ms/div
• Measurement condition: Vehicle run at 20 km/h (12 MPH) in L range with 1st gear Low & reverse brake solenoid valve control signal
• Measurement terminal: 6 of C-95 (+) & 22 of C-95 (-)
• Measurement scale: 5 volts/div & 10 ms/div
• Measurement condition: P or N range
2-4 brake solenoid valve control signal
• Measurement terminal: 7 of C-95 (+) & 22 of C-95 (-)
• Measurement scale: 5 volts/div & 10 ms/div
• Measurement condition: P or N range
0V
0V
0V
0V

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