2007 ISUZU KB P190 air condition

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–52
Step Action Yes No
6 1 Disconnect connector C-96 from the TCM.
2 Test circuits speed sensor circuits (between C-96 pin 16 and E-44 pin 2; C-96 pin 41 and E-44 pin 1) for the following
conditions:
• Short to ground
• Open circuit
• Short together
Did you find and correct the condition? Go to Step 9 Go to Step 8
7 Replace the vehicle speed sensor, refer to 7C4 Automatic
Transmission – 4L60E – On-vehicle Service.
Did you complete the replacement? Go to Step 9 —
8 Replace the TCM, refer to 7C4 Automatic Transmission – 4L60E –
On-vehicle Service.
Did you complete the replacement? Go to Step 9 —
9 Perform the following procedure to verify the repair:
1 On Tech 2 select: Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs.
2 Follow the instructions on Tech 2 and clear any DTCs.
3 Operate the vehicle so the transmission output speed is greater than 500 r.p.m. for 3 seconds.
4 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Has DTC P0722 set? Go to Step 2 Go to Step 9
10 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Does Tech 2 display any DTCs you have not diagnosed? Refer to
4.8 Diagnostic Trouble Code List System OK
When all diagnosis and repairs are completed, check the system for correct operation.
4.16 DTC P0723 – Vehicle Speed Sensor
Circuit Intermittent
DTC Description
This diagnostic procedure supports DTC P0723 Vehicle Speed Sensor Circuit Intermittent.
Circuit Description
The vehicle speed sensor (VSS) provides vehicle speed information to the transmission control module (TCM). The VSS
is a permanent magnet generator. The sensor is mounted in the extension housing facing the rear internal gear which is
splined to the output shaft assembly. As the output shaft and internal gear rotate, the toothed rotor of the internal gear
produces AC voltage as the rotor teeth pass through the magnetic field of the sensor. The AC voltage level and the
number of pulses increase as the speed of the vehicle increases. The TCM converts the voltage to vehicle speed. The
TCM uses the output shaft speed signal to determine shift timing and torque converter clutch (TCC) scheduling.
If the TCM detects an unrealistic drop in output shaft speed, DTC P0723 sets. DTC P0723 is a type B DTC.
Refer to 2 W iring Diagrams and Connector Chart to aid in diagnosis.
Conditions for Running the DTC
• No DTCs P0722, P1810, P1815 or P1816.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–55
Step Action Yes No
6 1 Disconnect connector C-96 from the TCM.
2 Test circuits speed sensor circuits (between C-96 pin 16 and E-44 pin 2; C-96 pin 41 and E-44 pin 1) for the following
conditions:
• Short to ground,
• Short to battery,
• Open circuit, and
• Short together.
Did you find and correct the condition? Go to Step 9 Go to Step 8
7 Replace the vehicle speed sensor, refer to 7C4 Automatic
Transmission – 4L60E – On-vehicle Service.
Did you complete the replacement? Go to Step 9 —
8 Replace the TCM, refer to 7C4 Automatic Transmission – 4L60E –
On-vehicle Service.
Did you complete the replacement? Go to Step 9 —
9 Perform the following procedure to verify the repair:
1 On Tech 2 select: Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs.
2 Follow the instructions on Tech 2 and clear any DTCs.
3 On Tech 2 select: Data Display / Transmission Data.
4 Operate the vehicle ensuring the transmission output speed drop is less than 500 r.p.m. for 2 seconds and output speed is
greater than 500 r.p.m.
5 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Has DTC P0723 set? Go to Step 2 Go to Step 10
10 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Does Tech 2 display any DTCs you have not diagnosed? Refer to
4.8 Diagnostic Trouble Code List System OK
When all diagnosis and repairs are completed, check the system for correct operation.
4.17 DTC P0724 – Brake Switch Circuit Low
Input (Stuck Off)
DTC Description
This diagnostic procedure supports DTC P0724 Brake Switch Circuit Low Voltage.
Circuit Description
The transmission control module receives a direct input from the stop lamp switch assembly. When the brake pedal is
pressed, 12 V is supplied to the TCM through connector C-96 pin 42.
When the TCM detects an open or short to ground on the stop lamp signal circuit during stopping then DTC P0724 sets.
DTC P0724 is a type C DTC.
Refer to 2 W iring Diagrams and Connector Chart to aid in diagnosis.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–57
Step Action Yes No
3 Test the stop lamp switch assembly, refer to 8B Cruise Control.
Is the stop lamp switch assembly serviceable? Go to Step 4 Replace the stop
lamp switch assembly
4 1 Disconnect connector C-96 from the TCM.
2 Using a multimeter set to measure voltage, probe between harness connector C-96 pin 42 and a known ground.
3 Press the brake pedal.
Does the multimeter display battery voltage? Go to Step 5 Repair or replace
affected circuit
Go to Step 6
5 Replace the TCM, refer to 7C4 Automatic Transmission – 4L60E –
On-vehicle Servicing.
Did you complete the replacement? Go to Step 6 —
6 Perform the following procedure to verify the repair:
1 On Tech 2 select: Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs.
2 Follow the instructions on Tech 2 and clear any DTCs.
3 Operate the vehicle under the following conditions:
• Turn on the ignition, with the engine off for at least
2 seconds.
• Start the vehicle and idle for 5 seconds.
• Drive in D4 from 0 – 60 km/h then brake, eight times in one
ignition cycle.
4 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Has DTC P0724 set? Go to Step 2 Go to Step 7
7 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Does Tech 2 display any DTCs you have not diagnosed? Refer to
4.8 Diagnostic Trouble Code List System OK
When all diagnosis and repairs are completed, check the
system for correct operation.
4.18 DTC P0741 – Torque Converter Clutch
System – Stuck Off
DTC Description
This diagnostic procedure supports DTC P0741 Torque Converter Clutch (TCC) System - Stuck Off.
Circuit Description
The torque converter clutch (TCC) solenoid valve is a normally-open exhaust valve that is used with the torque converter
clutch pulse width modulation (TCC PWM) solenoid valve to control fluid acting on the converter clutch apply valve. The
TCC solenoid valve attaches to the transmission case assembly extending into the pump cover. W hen grounded by the
transmission control module (TCM), the TCC solenoid valve stops converter signal oil from exhausting. This causes
converter signal oil pressure to increase and move the converter clutch apply valve against spring force and into the
apply position. In this position, release fluid is open to an exhaust port and converter feed fluid fills the apply fluid circu it.
The converter feed fluid applies the TCC. When the TCM no longer provides a ground path, the TCC solenoid valve de-
energizes and apply fluid exhausts, releasing the TCC.
When the TCM detects high torque converter slip when the TCC is commanded off, then DTC P0741 sets. DTC P0741 is
a type B DTC.
Refer to 2 W iring Diagrams and Connector Chart to aid in diagnosis.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–60
Step Action Yes No
4 Perform the following procedure to verify the repair:
1 On Tech 2 select: Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs.
2 Follow the instructions on Tech 2 and clear any DTCs.
3 On Tech 2 select: Automatic Transmission / Data Display / Transmission Data.
4 Drive the vehicle in D4 with the TCC on and the throttle above 10%. Ensure Tech 2 displays TCC Slip Speed between -25 to
+25 RPM for 3 seconds.
5 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Has DTC P0741 set? Go to Step 2 Go to Step 5
5 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Does Tech 2 display any DTCs you have not diagnosed? Refer to
4.8 Diagnostic Trouble Code List System OK
When all diagnosis and repairs are completed, check the system for correct operation.
4.19 DTC P0742 – Torque Converter Clutch
System – Stuck On
DTC Description
This diagnostic procedure supports DTC P0742 Torque Converter Clutch (TCC) System – Stuck On.
Circuit Description
The torque converter clutch (TCC) solenoid valve is a normally-open exhaust valve that is used with the torque converter
clutch pulse width modulation (TCC PWM) solenoid valve to control fluid acting on the converter clutch apply valve. The
TCC solenoid valve attaches to the transmission case assembly extending into the pump cover. W hen grounded by the
transmission control module (TCM), the TCC solenoid valve stops converter signal oil from exhausting. This causes
converter signal oil pressure to increase and move the converter clutch apply valve against spring force and into the
apply position. In this position, release fluid is open to an exhaust port and converter feed fluid fills the apply fluid circu it.
The converter feed fluid applies the TCC. When the TCM no longer provides a ground path, the TCC solenoid valve de-
energizes and apply fluid exhausts, releasing the TCC.
W hen the TCM detects low torque converter slip when the TCC is commanded off, then DTC P0742 sets. DTC P0742 is
a type B DTC.
Refer to 2 W iring Diagrams and Connector Chart to aid in diagnosis.
Conditions for Running the DTC
• No DTCs P0722, P0723, P0741 P02763, P02764, P02769 or P02770.
• Ignition voltage is 8 – 18 V.
• The engine run time is greater than 5 seconds.
• The IMS range is D4.
• The transmission fluid temperature is 10 – 130°C.
• The engine speed is 500 – 6,500 r.p.m. for 5 seconds, then 800 – 4,400 r.p.m.
• The engine torque is 156 – 881 Nm.
• The throttle position is greater than 10 percent.
• The transmission is not in 1st gear and the gear ratio is 0.95:1 – 1.56:1.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–62
Step Action Yes No
2 1 Connect Tech 2 to the DLC.
2 Turn on the ignition, with the engine off.
NOTE
Before clearing the DTC, use the Tech 2 Freeze
Frame/Failure Record to record the transmission
parameters at the time the DTC set. Using Tech 2 to clear
the DTC(s) erases the Freeze Frame/Failure Record
records from the TCM.
3 On Tech 2 select: Transmission / Automatic Transmission / Diagnostic
Trouble Codes / Freeze Frame.
4 Select the relevant DTC and note the parameters at the time of the DTC setting.
5 On Tech 2 select:
Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs.
6 Follow the instructions on Tech 2 and clear the DTCs.
7 On Tech 2 select: Automatic Transmission / Data Display / Transmission Data.
8 Drive the vehicle in the D4 drive range in second, third, or fourth gear under steady acceleration, with a TP angle at 10%.
On Tech 2, while TCC Solenoid status is On, is the TCC Slip Speed
within - 20 to +20 RPM ? Go to Step 3 Refer to Diagnostic
Aids within this Section
3 The TCC is hydraulically stuck ON. Inspect for the following:
• Blocked exhaust orifice in the TCC solenoid valve.
• Converter clutch apply valve stuck in the apply position.
• Incorrectly aligned or damaged valve body gasket.
• Restricted release passage.
• Restricted transmission cooler line.
Did you find and correct the condition? Go to Step 4 —
4 Perform the following procedure to verify the repair:
1 On Tech 2 select: Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs.
2 Follow the instructions on Tech 2 and clear any DTCs.
3 On Tech 2 select: Automatic Transmission / Data Display / Transmission Data.
4 Drive the vehicle in D4 with the TCC ON and the throttle above 10%. Ensure Tech 2 displays TCC Slip Speed between 100 –
2,500 RPM for 3 seconds.
5 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Has DTC P0742 set? Go to Step 2 Go to Step 5
5 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Does Tech 2 display any DTCs you have not diagnosed? Refer to
4.8 Diagnostic Trouble Code List System OK
When all diagnosis and repairs are completed, check the system for correct operation.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–65
Step Action Yes No
4 Perform the following procedure to verify the repair:
1 On Tech 2 select: Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs
2 Follow the instructions on Tech 2 and clear any DTCs.
3 Drive the vehicle in D4 range under the following conditions, only if traffic and road conditions permit:
• Hold the throttle at 20%, and
• Accelerate to 88 km/h.
4 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Has DTC P0751 set? Go to Step 2 Go to Step 5
5 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Does Tech 2 display any DTCs you have not diagnosed? Refer to
4.8 Diagnostic Trouble Code List System OK
When all diagnosis and repairs are completed, check the
system for correct operation.
4.21 DTC P0752 – 1-2 Shift Solenoid Valve
Performance – No Second or Third Gear
DTC Description
This diagnostic procedure supports DTC P0752 1-2 Shift Solenoid (SS) Valve Performance – No Second or Third Gear.
Circuit Description
The 1-2 shift solenoid (SS) valve controls the fluid flow acting on the 1-2 and 3-4 shift valves. The 1-2 SS valve is a
normally-open exhaust valve that is used with the 2-3 SS valve, to allow four different shifting combinations.
When the transmission control module (TCM) detects a 1-1-4-4 shift pattern, then DTC P0752 sets. DTC P0752 is a
type B DTC.
Refer to 2 W iring Diagrams and Connector Chart to aid in diagnosis.
Conditions for Running the DTC
• No DTCs P0722, P0723, P0742, P0894, P0973, P0974, P0976, or P0977.
• Ignition voltage is 8 – 18 V.
• The engine run time is greater than 5 seconds.
• The transmission fluid temperature is 20 – 130°C.
• The throttle position is greater than 10 percent.
• The output shaft speed is greater than 150 r.p.m.
• The engine torque is 108 – 882 Nm.
Conditions for Setting the DTC
The TCM commands 2nd gear and the resulting gear ratio is 2.42:1 – 2.52:1, 1st gear ratio for 2 seconds twice during
the same trip.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–67
Step Action Yes No
2 1 Connect Tech 2 to the DLC.
2 Turn on the ignition, with the engine off.
NOTE
Before clearing the DTC, use the Tech 2 Freeze
Frame/Failure Record to record the transmission
parameters at the time the DTC set. Using Tech 2 to clear
the DTC(s) erases the Freeze Frame/Failure Record
records from the TCM.
3 On Tech 2 select: Transmission / Automatic Transmission / Diagnostic
Trouble Codes / Freeze Frame.
4 Select the relevant DTC and note the parameters at the time of the DTC setting.
5 On Tech 2 select:
Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs.
6 Follow the instructions on Tech 2 and clear the DTCs.
7 Drive the vehicle in D4 range under the following conditions:
• Accelerate the vehicle, and
• Ensure the TCM commands 1st, 2nd, 3rd and 4th gears.
Did you detect a 1-1-4-4 shift pattern? Go to Step 3 Refer to Diagnostic
Aids within this Section
3 Inspect the shift solenoid/hydraulic circuit for the following conditions:
• An internal malfunction.
• Damaged seals on the shift solenoid valve. Perform the shift
solenoid leak test, refer to 7C3 Automatic Transmission – 4L60E
– Hydraulic and Mechanical Diagnosis.
Did you find and correct the condition? Go to Step 4 —
4 Perform the following procedure to verify the repair:
1 On Tech 2 select: Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs
2 Follow the instructions on Tech 2 and clear any DTCs.
3 Drive the vehicle in D4 range under the following conditions, only if traffic and road conditions permit:
• Hold the throttle at 20%, and
• Accelerate to 88 km/h.
4 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Has DTC P0752 set? Go to Step 2 Go to Step 5
5 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Does Tech 2 display any DTCs you have not diagnosed? Refer to
4.8 Diagnostic
Trouble Code List System OK
When all diagnosis and repairs are completed, check the
system for correct operation.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007

Automatic Transmission – 4L60E – Electrical Diagnosis Page 7C2–70
Step Action Yes No
3 1 Inspect the shift solenoid/hydraulic circuit for the following
conditions:
• Debris or chips in the AFL oil passage.
• Debris or chips restricting oil flow in passage #29 of the
case or through the spacer plate gasket into the valve
body.
• A cracked 2-3 shift solenoid.
• A 2-3 shift valve which is stuck or hung up in the valve
body bore.
• A 2-3 shuttle valve which is stuck or hung up in its bore.
• Damaged seals on the shift solenoid valves. Perform the
shift solenoid leak test, refer to 7C3 Automatic
Transmission – 4L60E – Hydraulic and Mechanical
Diagnosis.
2 Clean and inspect the related valves, bores and the valve body for debris or contamination.
Did you find and correct the condition? Go to Step 4 —
4 Perform the following procedure to verify the repair:
1 On Tech 2 select: Diagnostic Trouble Codes / Clear Engine & Transmission
DTCs
2 Follow the instructions on Tech 2 and clear any DTCs.
3 Drive the vehicle in D4 range under the following conditions, only if traffic and road conditions permit:
• Hold the throttle at 40%, and
• Accelerate to 64 km/h.
4 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Has DTC P0756 set? Go to Step 2 Go to Step 5
5 On Tech 2 select:
Diagnostic Trouble Codes / Read DTC Information.
Does Tech 2 display any DTCs you have not diagnosed? Refer to
4.8 Diagnostic Trouble Code List System OK
When all diagnosis and repairs are completed, check the system for correct operation.
4.23 DTC P0757 – 2-3 Shift Solenoid Valve
Performance – No Third or Fourth Gear
DTC Description
This diagnostic procedure supports DTC P0757 2-3 Shift Solenoid (SS) Valve Performance – No Third or Fourth Gear.
Circuit Description
The 2-3 shift solenoid (SS) valve controls the fluid flow acting on the 2-3 shift valves. The 2-3 SS valve is a normally-
open exhaust valve that is used with the 1-2 SS valve to allow four different shifting combinations.
When the transmission control module (TCM) detects a 1-2-2-1 shift pattern, then DTC P0757 sets. DTC P0757 is a
type A DTC.
Refer to 2 W iring Diagrams and Connector Chart to aid in diagnosis.

BACK TO CHAPTER INDEX
TO MODEL INDEX
ISUZU KB P190 2007