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For 1990-2009 cars only

DTC P0733 Non-European Emissions

Circuit Description

The transmission control module (TCM) uses transaxle input speed information and output speed sensor to control line pressure, torque converter clutch (TCC) apply and release, and transaxle shift patterns. This information is also used to calculate the appropriate operating gear ratios and the TCC slippage.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0733 Incorrect 3rd Gear Ratio

Conditions for Setting the DTC

    • Time since TCM reset is greater than 500 ms.
    • Time since shift end is greater than 500 ms.
    • Transmission oil temperature is greater than -10°C (14°F).
    • System voltage is greater than 9 volts.
    • No input speed error DTCs P0715, P0716, and P0717
    • Output speed is greater than 256 RPM.
    • Input speed is greater than 400 RPM.
    • No gear shift active

Action Taken When the DTC Sets

    • The hold lamp will blink.
    • The TCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records buffer.
    • Adopt Emergency/Substitute mode and constant 4th gear.
    • High line pressure

Conditions for Clearing the Hold Lamp/DTC

    • The hold lamp will turn OFF when the malfunction has not occurred after 3 ignition cycles.
    • A history DTC will clear after 40 consecutive warm-up cycles without a fault.
    • Using a scan tool can clear history DTCs.

Diagnostic Aids

    • Inspect for intermittent input speed sensor or output speed sensor circuit problems.
    • Inspect for possible incorrect calibration.

DTC P0733

Step

Action

Values

Yes

No

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Visually inspect the transaxle cooling system for fluid leaks.

Was the condition found and corrected?

--

Go to Step 7

Go to Step 3

3

Has the transaxle fluid checking procedure been performed?

--

Go to Step 4

Go to Transmission Fluid Level Inspection

4

  1. Using the scan tool record each transaxle drive range.
  2. Drive the vehicle in transaxle gear ranges 1, 2, 3 and D, with throttle position (TP) greater than 15 percent and vehicle speed greater than 16 km/h (10 mph) for 5 seconds.

Does commanded gear ratio match ranges as shown?

1st = 2.719

2nd = 1.487

3rd = 1.000

4th = 0.717

Go to Diagnostic Aids

Go to Step 5

5

Perform a line pressure inspection.

Was the condition found and corrected?

--

Go to Step 7

Go to Step 6

6

Inspect for possible clutch slippage.

Was the condition found and corrected?

--

Go to Step 7

--

7

  1. After the repair, use a scan tool "clear info" function.
  2. Road test the vehicle.
  3. Review the DTC info.

Has the last test failed or is the current DTC displayed?

--

Go to Step 8

System OK

8

Replace the transaxle assembly. Refer to Transmission Replacement .

Did you complete the replacement?

--

Go to Step 9

--

9

  1. After the repair, use a scan tool "clear info" function.
  2. Road test the vehicle.
  3. Review the DTC info.

Has the last test failed or is the current DTC displayed?

--

Go to Step 2

System OK

DTC P0733 European Emissions

Circuit Description

The transmission control module (TCM) uses transaxle input speed information and output speed sensor to control line pressure, torque converter clutch (TCC) apply and release, and transaxle shift patterns. This information is also used to calculate the appropriate operating gear ratios and the TCC slippage.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P0733 Incorrect 3rd Gear Ratio

Conditions for Setting the DTC

    • Time since TCM reset is greater than 500 ms.
    • Time since shift end is greater than 500 ms.
    • Transmission oil temperature is greater than -10°C (14°F).
    • System voltage is greater than 9 volts.
    • No input speed error DTCs P0715, P0716, and P0717
    • Output speed is greater than 256 RPM.
    • Input speed is greater than 400 RPM.
    • No gear shift active

Action Taken When the DTC Sets

    • The malfunction indicator lamp (MIL) will illuminate.
    • The TCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records buffer.
    • Adopt Emergency/Substitute mode and constant 4th gear.
    • High line pressure

Conditions for Clearing the MIL/DTC

    • The MIL will turn OFF when the malfunction has not occurred after 3 ignition cycles.
    • A history DTC will clear after 40 consecutive warm-up cycles without a fault.
    • Using a scan tool can clear history DTCs.

Diagnostic Aids

    • Inspect for intermittent input speed sensor or output speed sensor circuit problems.
    • Inspect for possible incorrect calibration.

DTC P0733

Step

Action

Values

Yes

No

1

Did you perform the Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Visually inspect the transaxle cooling system for fluid leaks.

Was the condition found and corrected?

--

Go to Step 7

Go to Step 3

3

Has the transaxle fluid checking procedure been performed?

--

Go to Step 4

Go to Transmission Fluid Level Inspection

4

  1. Using the scan tool record each transaxle drive range.
  2. Drive the vehicle in transaxle gear ranges 1, 2, 3 and D, with throttle position (TP) greater than 15 percent and vehicle speed greater than 16 km/h (10 mph) for 5 seconds.

Does commanded gear ratio match ranges as shown?

1st = 2.719

2nd = 1.487

3rd = 1.000

4th = 0.717

Go to Diagnostic Aids

Go to Step 5

5

Perform a line pressure inspection.

Was the condition found and corrected?

--

Go to Step 7

Go to Step 6

6

Inspect for possible clutch slippage.

Was the condition found and corrected?

--

Go to Step 7

--

7

  1. After the repair, use a scan tool "clear info" function.
  2. Road test the vehicle.
  3. Review the DTC info.

Has the last test failed or is the current DTC displayed?

--

Go to Step 8

System OK

8

Replace the transaxle assembly. Refer to Transmission Replacement .

Did you complete the replacement?

--

Go to Step 9

--

9

  1. After the repair, use a scan tool "clear info" function.
  2. Road test the vehicle.
  3. Review the DTC info.

Has the last test failed or is the current DTC displayed?

--

Go to Step 2

System OK