Isuzu Amigo / Axiom / Trooper / Rodeo / VehiCross. Manual - part 933

7A1–52 TRANSMISSION CONTROL SYSTEM (4L30–E)

Test Description

The numbers below refer to the step numbers on the
diagnostic chart.
2. This step isolates the brake switch as a source for

setting the DTC.

DTC P0724 Brake Switch Circuit High (Stuck Off) 

Step

Action

Yes

No

1

Was the Powertrain On–Board Diagnostic (OBD) System Check
performed?

Go to Step 2

Go to Powertrain

OBD System

Check

2

1. Install the scan tool.
2. With the engine “off,” turn the ignition switch to the “on”

position.

NOTE: Before clearing the DTC(s), use the scan tool in order to
record the “Failure Records” for reference. Using the “Clear Info”
function will erase the stored “Failure Records” from the PCM. 

3. Record the DTC Failure Records, then clear the DTC(s).
4. Select “TCC Brake Switch” on the scan tool.
5. Disconnect the brake switch connector from the brake switch.

Did the TCC brake switch status change from “Closed” to “Open”?

Go to Step 3

Go to Step 4

3

Replace the brake switch.

Is the replacement complete?

Go to Step 6

—

4

Inspect circuit ORN for a short to B+ condition. Repair the circuit if
necessary.

Did you find a short to B+ condition?

Go to Step 6

Go to Step 5

5

Replace the PCM.

Is the replacement complete?

Go to Step 6

—

6

In order to verify your repair, perform the following procedure:
1. Select DTC.
2. Select “Clear Info”.
3. With the engine “off” turn the ignition switch to the “on” position.
4. Apply the brake pedal.
5. Verify that the TCC brake switch status indicates “Open” (0

volts) for 2 seconds.

6. Select Specific DTC. Enter DTC P0724.

Has the test run and passed?

System OK

Begin the

diagnosis again.

Go to Step 1

TRANSMISSION CONTROL SYSTEM (4L30–E)

7A1–53

DTC P0730 Gear Error Without Input Speed

D07RY00055

Circuit Description

D

The Powertrain Control Module (PCM) calculates the
slippage of the converter and transmission based
upon the engine speed, the output speed, and the
current gear ratio.

D

The slippage of the converter at a high enough engine
speed is low.  The transmission should not slip more
than a given value when there is no shift.

D

This DTC detects a slip at each gear.  This is a type
“C” DTC.

Conditions For Setting The DTC

D

No Output Speed Sensor DTC(s) P0722, P0723.

D

Not in Park, Neutral, or Reverse.

D

Engine speed is greater than 3,500 rpm.

D

3 seconds since upshift.

D

No Transmission Range Switch DTC(s) P0705,
P0706.

D

3 seconds since downshift.

D

3 seconds since garage shift (N

→

D).

D

And one of the following conditions occur:

–  Slip is greater than 508 rpm in 1st gear.

–  Slip is greater than 468 rpm in 2nd gear.

–  Slip is greater than 449 rpm on 3rd gear.

–  Slip is greater than 440 rpm on 4th gear.

D

All conditions met for 5.5 seconds.

Action Taken When The DTC Sets

D

Maximum line pressure.

D

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

7A1–54 TRANSMISSION CONTROL SYSTEM (4L30–E)

D

The PCM will illuminate the CHECK TRANS Lamp.

D

Turn force motor OFF.

Conditions For Clearing The DTC/CHECK
TRANS Lamp

D

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

D

The DTC can be cleared from PCM memory by using
a scan tool.  

D

The DTC can also be cleared from memory when the
vehicle has made 40 warmup cycles without a failure
reported.

D

The PCM will cancel the DTC Actions Taken items
when the fault conditions no longer exist and the
ignition is cycles “off” long enough to power down the
PCM.

Diagnostic Aids

D

Check for intermittent output speed sensor circuit
problems.

D

Check for possible incorrect calibration. (PCM part
No., tire specification, and rear axle ratio)

Test Description

The numbers below refer to the step numbers on the
diagnostic chart:
3. This step checks for possible low fluid level causing

slipping resulting in an undefined gear ratio.

4. This step checks for correct gear ratios for

commanded gears.

5. This step checks for low line pressure.

DTC P0730 Gear Error Without Input Speed 

Step

Action

Yes

No

1

Were you sent here from the “On–Board Diagnostic (OBD)
System Check”?

Go to Step 2

Go to OBD

System Check

Refer to

Driveability and

Emission in

Engine section

2

Visually inspect the transmission cooling system for fluid leaks.

D

Refer to Chart 16: Possible Causes of Transmission Fluid
Leaks of Mechanical/Hydraulic Diagnosis Symptoms Index in
Automatic Transmission (4L30–E) section

Was condition found and corrected?

Go to Step 7

Go to Step 3

3

Refer to Checking Transmission Fluid Level and Condition in
Automatic Transmission (4L30–E) section.

Has transmission fluid checking procedure been performed?

Go to Step 4

Go to Checking

Transmission

Fluid Level and

Condition in

Automatic

Transmission

(4L30–E) section

4

1. Install the scan tool.
2. Turn the ignition switch to the “on” position.
3. Engine not running.

NOTE: Before clearing DTC(s) use the scan tool to record the
“Failure Records” for reference, as data will be lost when the “Clear
Info” function is used.

4. Record the Failure Record data.
5. Use the scan tool snapshot mode to record transmission gear

ratios.

6. Drive vehicle in transmission gear ranges 1, 2, 3, and D with

the engine speed is greater than 3,500 rpm for 5.5 seconds.

7. Record each transmission gear.

1st:2.73 – 2.99
2nd:1.54 – 1.71
3rd:0.93 – 1.05
4th:0.66 – 0.78

Does commanded gear ratio match ranges as shown?

Refer to

Diagnostic Aids

Go to Step 5

TRANSMISSION CONTROL SYSTEM (4L30–E)

7A1–55

DTC P0730 Gear Error Without Input Speed  (Cont’d)

Step

No

Yes

Action

5

Perform line pressure check.

D

Refer to Line Pressure Test in Automatic Transmission
(4L30–E) section.

Was condition found and corrected?

Go to Step 7

Go to Step 6

6

Check for possible clutch slippage.

D

Refer to Chart 6: Diagnostic Trouble Code (DTC) P0730 of
Mechanical/Hydraulic Diagnosis Symptoms Index in
Automatic Transmission (4L30–E) section.

Was condition found and corrected?

Go to Step 7

—

7

1. After the repair is complete, use the scan tool to select “DTC”,

then “Clear info” function.

2. Operate the vehicle under the following conditions:

D

Drive the vehicle in D4 with the engine speed greater than
3,500 rpm to obtain anyone of the following gear ratios for
seven seconds.

1st 1:2.73 – 1:2.99

2nd 1:1.54 – 1:1.71

3rd 1:0.93 – 1:1.05

4th 1:0.66 – 1:0.78

Has the  last test failed?

Begin diagnosis

again

Go to Step 1

Repair verified
Exit DTC table