2002 ISUZU AXIOM ignition

7A1±36
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0712 Transmission Fluid Temperature (TFT) Sensor Circuit Low Input
D07R200004
Circuit Description
The TFT sensor is a thermister that controls the signal
voltage to the PCM. The PCM supplies a 5±volt reference
signal to the sensor on circuit RED/BLK. When the
transmission fluid is cold, the sensor resistance is high.
The PCM detects high signal voltage. As the
transmission fluid temperature increases to the normal
operating temperature of 100
C (212
F), the sensor
resistance becomes less and the voltage decreases to
1.5 to 2 volts. With transmission fluid over temperature
and DTC P0218 also set, check the transmission cooling
system.
This DTC detects a continuous short to ground in the TFT
signal circuit or the TFT sensor. This is a type ªDº DTC.
Conditions For Setting The DTC

Battery voltage is between 10 and 16 volts.

Ignition is ªonº.

TFT sensor indicating a voltage less than 0.4 volts.

All conditions met for 20 seconds.
Action Taken When The DTC Sets

Transmission default temperature will be:
80
C (176
F) if engine temperature code is set.
100
C (212
F) if engine temperature is warm.
80
C (176
F) if engine run time is greater than 5
minutes.
21
C (69.8
F) if engine run time is less than 5
minutes.

The PCM will not illuminate the Malfunction Indicator
Lamp (MIL).
Conditions For Clearing The DTC

The DTC can be cleared from the PCM history by
using a scan tool.
The DTC will be cleared from history when the vehicle
has achieved 40 warmup cycles without a failure
reported.

The PCM will cancel the DTC default actions when
the fault no longer exists and the ignition is cycled ªoffº
long enough to power down the PCM.
Diagnostic Aids

Check harness routing for a potential short to ground
in circuit RED/BLK. Scan tool TFT display should rise
steadily to about 100
C (212
F), then stabilize.

Inspect the wiring for poor electrical connection at the
PCM and transmission 7-way connector. 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.

When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.

The temperature to resistance value scale may be
used to test the TFT sensor at the various
temperature levels to evaluate the possibility of a
ªskewedº (mis±scaled) sensor.
A ªskewedº sensor could result in delayed garage
shifts or TCC complaints.

Verify customer driving habits, trailer towing, etc.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
3. This test checks for a short to ground or a ªskewedº
sensor.
4. This test checks for an internal fault within the
transmission by creating an open.

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±37
DTC P0712 Transmission Fluid Temperature (TFT) Sensor Circuit Low Input
StepActionYe sNo
1Were you sent here from the ªPowertrain On±Board Diagnostic
(OBD) System Checkº?
Go to Step 2
Go to OBD
System Check
Refer to
Driveability and
Emissions in
Engine section
2Perform the transmission fluid checking procedure. Refer to
Checking Transmission Fluid Level and Condition in Automatic
Transmission (4L30±E) section
Was the fluid checking procedure performed?
Go to Step 3
Refer to
Checking
Transmission
Fluid Level and
Condition in
Automatic
Transmission
(4L30±E) section
31. Install the scan tool.
2. With the engine ªoffº, turn the ignition switch ªonº.
NOTE: Before clearing DTC(s), use the scan tool to record ªFreeze
Frameº and ªFailure Recordsº for reference, as data will be lost
when the ªClear Infoº function is used.
3. Record the DTC ªFreeze Frameº and ªFailure Recordsº.
Does the scan tool display a TFT sensor signal voltage less than
0.4 volts?
Go to Step 4
Go to Diagnostic
Aids
41. Turn the ignition ªoffº.
2. Disconnect the transmission 7±way connector E±42.
3. Turn the ignition ªonº.
Does the TFT signal voltage change to match the voltage 4.92
volts?
Go to Step 5Go to Step 10
5Using the J39200 DVOM, measure the resistance between
terminals E42±4(F) and E42±1(E).
Is the resistance within specifications? (See Transmission Fluid
Temperature (TFT) Sensor Specifications.)
Go to Diagnostic
Aids
Go to Step 6
61. Disconnect the transmission 7±way connector E±42.
2. Using the J39200 DVOM, measure the resistance between
terminals E42±4(F) and E42±1(E).
Is the resistance within specifications? (See Transmission Fluid
Temperature (TFT) Sensor Specifications.)
Go to Diagnostic
Aids
Go to Step 7
71. Remove the transmission oil pan. Refer to Transmission Oil
Temperature Sensor (Main Case) in Automatic Transmission
(4L30±E) section.
2. Check the internal wiring harness for a short to ground.
Was a problem found?
Go to Step 9Go to Step 8
81. Disconnect the internal wiring harness at the TFT sensor.
2. Measure the resistance of the TFT sensor.
Is the resistance within specifications? (See Transmission Fluid
Temperature (TFT) Sensor Specifications.)
Go to Diagnostic
Aids
Go to Step 9
9Replace the TFT Sensor.
Is the replacement complete?
Go to Step 13Ð
10Check circuit RED/BLK for a short to ground.
Was a problem found?
Go to Step 13Go to Step 11

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±39
DTC P0713 Transmission Fluid Temperature (TFT) Sensor Circuit High Input
D07R200004
Circuit Description
The TFT sensor is a thermistor that controls the signal
voltage to the PCM. The PCM supplies a 5±volt reference
signal to the sensor on circuit RED/BLK. When the
transmission fluid is cold, the sensor resistance is high
and the PCM will sense high signal voltage. As the
transmission fluid temperature warms to the normal
operating temperature of 100
C (212
F), the sensor
resistance becomes less and the voltage decreases to
about 1.5 to 2 volts.
This DTC detects a continuous open or short to power in
the TFT signal circuit or the TFT sensor. This is a type ªDº
DTC.
Conditions For Setting The DTC

Battery voltage is between 10 and 16 volts.

Ignition is ªonº.

TFT sensor indicating a voltage greater than 4.86
volts.

All conditions met for 20 seconds.
Action Taken When The DTC Sets

Transmission default temperature will be:
80
C (176
F) if engine temperature code is set.
100
C (212
F) if engine temperature is warm.
80
C (176
F) if engine run time is greater than 5
minutes.
21
C (69.8
F) if engine run time is less than 5
minutes.

The PCM will not illuminate the Malfunction Indicator
Lamp (MIL).
Conditions For Clearing The DTC

The DTC can be cleared from the PCM history by
using a scan tool.
The DTC will be cleared from history when the vehicle
has achieved 40 warmup cycles without a failure
reported.

The PCM will cancel the DTC default actions when
the fault no longer exists and the ignition is cycled ªoffº
long enough to power down the PCM.
Diagnostic Aids

Inspect the wiring for poor electrical connection at the
PCM and transmission 7-way connector. 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.

When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.

Scan tool displays transmission fluid temperature in
degrees. After transmission is operating, the
temperature should rise steadily to about 100
C
(212
F), then stabilize.

The temperature to resistance value scale may be
used to check the TFT sensor at the various
temperature levels to evaluate the possibility of a
ªskewedº (mis±scaled) sensor.
A ªskewedº sensor could result in hard shifts or TCC
complaints.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
3. This check verifies problem in the TFT sensor circuit.
4. This test simulates a TFT sensor DTC P0712. If the
PCM recognizes the low signal voltage (high
temperature), and the scan tool displays 146
C
(295
F) or greater, the PCM and wiring are OK.
5. This test checks the TFT sensor and internal wiring
harness.

7A1±40
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0713 Transmission Fluid Temperature (TFT) Sensor Circuit High Input
StepActionYe sNo
1Were you sent here from the ªPowertrain On±Board Diagnostic
(OBD) System Checkº?
Go to Step 2
Go to OBD
System Check
Refer to
Driveability and
Emission in
Engine section
2Perform the transmission fluid checking procedure.
Refer to
Checking Transmission Fluid Level and Condition in
Automatic Transmission (4L30±E) section.
Was the fluid checking procedure performed?
Go to Step 3
Refer to
Checking
Transmission
Fluid Level and
Condition in
Automatic
Transmission
(4L30±E) section
31. Install the scan tool.
2. With the engine ªoffº, turn the ignition switch ªonº.
NOTE: Before clearing DTC(s), use the scan tool to record ªFreeze
Frameº and ªFailure Recordsº for reference, as data will be lost
when the ªClear Infoº function is used.
3. Record the DTC ªFreeze Frameº and ªFailure Recordsº.
Does the scan tool display a TFT sensor signal voltage greater
than 4.86 volts?
Go to Step 4
Go to Diagnostic
Aids
41. Turn the ignition ªoffº.
2. Disconnect the transmission 7±way connector E±42.
3. Install a fused jumper wire from terminal E42±4(F) to
E42±1(E) on the engine harness.
4. Turn the ignition ªonº.
Does the TFT signal voltage drop to less than 0.4 volts?
Go to Step 5Go to Step 10
51. Turn the ignition ªoffº.
2. Using the J39200 DVOM, measure the resistance between
terminals E42±4(F) and E42±1(E).
Is the resistance within specifications? (See Transmission Fluid
Temperature (TFT) Sensor Specifications.)
Go to Diagnostic
Aids
Go to Step 6
61. Disconnect the transmission 7±way connector E±42.
2. Using the J39200 DVOM, measure the resistance between
terminals E42±4(F) and E42±1(E).
Is the resistance within specifications? (See Transmission Fluid
Temperature (TFT) Sensor Specifications.)
Go to Diagnostic
Aids
Go to Step 7
71. Remove the transmission oil pan.
2. Check the internal wiring harness for an open. Refer to
Transmission Oil Temperature Sensor (Main Case) in
Automatic Transmission (4L30±E) section.
Was a problem found and corrected?Go to Step 14Go to Step 8
81. Disconnect the internal wiring harness at the TFT sensor.
2. Measure the resistance of the TFT sensor.
Is the resistance within specifications? (See Transmission Fluid
Temperature (TFT) Sensor Specifications.)
Go to Diagnostic
Aids
Go to Step 9
9Replace TFT sensor. Refer to Transmission Oil Temperature
Sensor (Main Case) in Automatic Transmission (4L30±E) section.
Is the replacement complete?Go to Step 14Ð

7A1±42
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0719 Brake Switch Circuit Low (Stuck On)
D07R200007
Circuit Description:
The brake switch indicates brake pedal status to the
Powertrain Control Module (PCM). The brake switch is a
normally±closed switch that supplies battery voltage on
circuit BRN/RED to the PCM. Applying the brake pedal
opens the switch, interrupting voltage to the PCM. When
the brake pedal is released, the PCM receives a constant
voltage signal. If the PCM receives a zero voltage signal
at the brake switch input, and the Torque Converter
Clutch (TCC) is engaged, the PCM de±energizes the
Torque Converter Clutch Solenoid Valve (TCC Sol.
Valve). The PCM disregards the brake switch input for
TCC scheduling if there is a brake switch circuit fault
(Refer to
Diagnostic Aids).
When the PCM detects an open brake switch circuit (0
volts, low input) during accelerations, then DTC P0719
sets. DTC P0719 is a type D DTC.
Conditions For Setting The DTC

No OSS Assy. DTCs P0722 or P0723.

The PCM detects an open brake switch or circuit (0
volts) for 15 minutes without changing for 2 seconds,
and the following events occur seven consecutive
times.

The vehicle speed is less than 8 km/h (5 mph).

then the vehicle speed is 8±32 km/h (5±20 mph) for
4 seconds.

then the vehicle speed is greater than 32 km/h (20
mph) for 4 seconds.
Action Taken When The DTC Sets

The PCM does not illuminate the Malfunction
Indicator Lamp (MIL).

DTC P0719 stores in PCM history.
Conditions For Clearing The DTC

A scan tool can clear the DTC from the PCM history.
The PCM clears the DTC from the PCM history if the
vehicle completes 40 warm±up cycles without a
failure reported.

The PCM cancels the DTC default actions when the
fault no longer exists and the ignition is OFF long
enough in order to power down the PCM.
Diagnostic Aids

Inspect the wiring for poor electrical connections at
the PCM and brake switch. 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.

When diagnosing for a possible intermittent short or
open condition, move the wiring harness while
observing test equipment for a change.

Check customer driving habits and/or unusual driving
conditions (i.e. stop and go, highway).

Check brake switch for proper mounting and
adjustment.

7A1±44
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0719 Brake Switch Circuit Low (Stuck On)
StepActionYe sNo
1Was the Powertrain On±Board Diagnostic (OBD) System Check
performed?
Go to Step 2
Go to Powertrain
OBD System
Check
21. Install the scan tool.
2. With the engine ªoff,º turn the ignition switch to the ªonº
position.
NOTE: Before clearing the DTC(s), use the scan tool in order to
record the ªFailure Recordsº for reference. Using the ªClear Infoº
function will erase the stored ªFailure Recordsº from the PCM.
3. Record the ªDTC Failure Recordsº, then clear the DTC(s).
4. Select ªTCC Brake Switchº on the scan tool.
5. Disconnect the brake switch connector from the brake switch.
6. Connect a test lamp from cavity I31±3 of the brake switch
connector to a known good ground.
Is the test lamp ON?
Go to Step 3Go to Step 4
3Install a J 36169±A Fused Jumper Wire from terminal I31±2 to
terminal I31±3 of the brake switch connector.
Did the TCC Brake Switch status change from Open to Closed?
Go to Step 7Go to Step 9
41. Remove the fuse ªTURN, BACK UPº.
2. Inspect the fuse for an open.
Is the fuse open?
Go to Step 5Go to Step 8
5Inspect circuit WHT/GRN for a short to ground condition. Repair
the circuit if necessary.
Did you find a short to ground condition?
Go to Step 11Go to Step 6
6Inspect circuit BRN/RED for a short to ground condition. Repair
the circuit if necessary.
Did you find a short to ground condition?
Go to Step 11Go to Step 10
7Replace the brake switch.
Is the replacement complete?
Go to Step 11Ð
8Inspect circuit WHT/GRN for an open condition. Repair the circuit
if necessary.
Did you find and correct an open condition?
Go to Step 11Ð
9Inspect circuit BRN/RED for an open.
Did you find an open condition?
Go to Step 11Go to Step 10
10Replace the PCM.
Is the replacement complete?
Go to Step 11Ð
11In order to verify your repair, perform the following procedure:
1. Select DTC.
2. Select Clear Info.
3. With the engine ªoff,º turn the ignition switch to the ªonº
position.
4. Do not depress the brake pedal.
5. Verify that the Brake Switch status indicates ªClosedº (12
volts) for 2 seconds.
6. Select Specific DTC. Enter DTC P0719.
Has the test run and passed?
System OK
Begin the
diagnosis again.
Go to
Step 1

TRANSMISSION CONTROL SYSTEM (4L30±E)7A1±45
DTC P0722 Automatic Transmission Output Speed Sensor (OSS) Low Input
D07R200006
Circuit Description
Output speed information is provided to the PCM by the
OSS, which is a permanent magnet (PM) generator. The
PM generator produces a pulsing AC voltage. The AC
voltage level and number of pulses increases as the
speed of the vehicle increases. The PCM then converts
the pulsing voltage to output speed, which is used for
calculations. The vehicle speed can be displayed with a
scan tool.
This DTC detects a low output speed when there is a high
engine speed in a drive gear range. This is a type ªBº
DTC.
Conditions For Setting The DTC

No MAP DTCs P0107 or P0108, P0106, P1106,
P1107.

No TPS DTCs P0122 or P0123.

Not in Park or Neutral.

TP angle is greater than 10%.

Engine vacuum is between 0 and 70kPa.

Engine speed is between 3000 and 7000 rpm.

Transmission output speed is less than 0 rpm.

All conditions met for 5 seconds.
Action Taken When The DTC Sets

Fixed to 4th gear.

Maximum line pressure.

Inhibit TCC engagement.

For lamp illuminate refer to
DTC type definition (type
B).
Conditions For Clearing The MIL/DTC

The PCM will turn off the MIL and CHECK TRANS
Lamp after three consecutive ignition cycles without a
failure reported.

The DTC can be cleared from the PCM history by
using a scan tool. The DTC will be cleared from
history when the vehicle has achieved 40 warmup
cycles without a failure reported.

The PCM will cancel the DTC default actions when
the fault no longer exists and the ignition is cycled ªoffº
long enough to power down the PCM.
Diagnostic Aids

An OSS DTC P0722 will set when no output speed is
at detected at start off.

Inspect the wiring for poor electrical connection at the
PCM. 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.

When diagnosing for a possible intermittent short or
open condition, move or massage the wiring harness
while observing test equipment for a change.
Test Description
The numbers below refer to the step numbers on the
diagnostic chart:
4. This test checks the OSS circuit.
5. This test checks the integrity of the OSS.
7. This test checks the 5±volt and ground circuit of the
PCM.

7A1±46
TRANSMISSION CONTROL SYSTEM (4L30±E)
DTC P0722 Automatic Transmission Output Speed Sensor (OSS) Low Input
StepActionYe sNo
1Were you sent here from the ªPowertrain On±Board Diagnostic
(OBD) System Checkº?
Go to Step 2
Go to OBD
System Check
Refer to
Driveability and
Emissions in
Engine section
21. Install the scan tool.
2. With the engine ªoffº, turn the ignition switch ªonº.
NOTE: Before clearing DTC(s), use the scan tool to record ªFreeze
Frameº and ªFailure Recordsº for reference, as data will be lost
when the ªClear Infoº function is used.
3. Record the DTC ªFreeze Frameº and ªFailure Recordsº.
4. Raise the drive wheels.
5. Start the engine.
6. Place the transmission in any drive range.
With the drive wheels rotating, does the ªTrans Output Speedº
increase with the drive wheel speed?
Go to Diagnostic
Aids
Go to Step 3
3Check for the most current and/or incorrect calibration.
Is the calibration current?
Go to Step 16Go to Step 4
41. Turn the ignition ªoffº.
2. Disconnect the E35 (RED) PCM connector.
3. Using the J39200 DVOM, measure the resistance between
harness connector terminals E35±22 and E35±55.
Is the reading 3000 ohms?
Go to Step 5Go to Step 6
51. Select AC volts.
2. Rotate the rear wheels, ensuring the driveshaft is turning.
Is the voltage greater than 0.5 volts?
Go to Step 7Go to Step 8
6Inspect circuits BLU/YEL and BLU/GRN for a poor connection or
an open circuit.
Was a problem found?
Go to Step 17Go to Step 8
71. Reconnect the E35 (RED) PCM connector.
2. Disconnect the OSS harness from the OSS.
3. With the engine ªoffº, turn the ignition ªonº.
4. Using the J 39200 DVOM, measure the voltage at the OSS
harness connector terminals E44±1 and E44±2.
Is the reading between 4.0 to 5.1 volts?
Go to Step 16Go to Step 10
81. Remove the OSS.
2. Check the output shaft speed sensor rotor for damage or
misalignment. Refer to
Speed Sensor (Extension Assembly)
in Automatic Transmission (4L30±E) section.
Was a problem found?Go to Step 17Go to Step 9
9Replace the OSS.
Is the replacement complete?
Go to Step 17Ð
10Was the reading in step 7 less than 4.0 volts?Go to Step 12Go to Step 11
11Was the reading in Step 7 greater than 5.1 volts?Go to Step 15Ð
12Using the J 39200 DVOM to chassis ground, measure the voltage
on circuit BLU/YEL.
Is the reading between 4.0 to 5.1 volts?
Go to Step 13Go to Step 14