P0730

DTC P0730





Test 1-8





Test 9-11

Circuit Description with 4L80-E / 4L85-E Automatic Transmission
The Powertrain Control Module (PCM) calculates a ratio based on the automatic transmission Input Shaft Speed (ISS) sensor and Output Shaft Speed (OSS) sensor readings. The PCM compares the known transmission gear ratio to the calculated ratio, for the selected gear range. If the PCM detects an incorrect gear ratio, then DTC P0730 sets. DTC P0730 is a type C DTC.

Conditions for Running the DTC
^ No MAP DTCs P0106, P0107, P0108.
^ No AT ISS sensor DTCs P0716 or P0717.
^ No AT VSS sensor DTCs P0722 or P0723.
^ No TFP manual valve position switch DTC P1810.
^ The vehicle speed is greater than 8 km/h (5 mph).
^ The APP angle is greater than 25 percent.
^ The TFT is greater than 20°C (68°F).
^ System voltage is 8 - 18 volts.
^ 10 seconds must have elapsed since the last gear range change.
^ The engine speed is greater than 475 RPM for at least 7 seconds.
^ The engine speed is less than 3,750 RPM.
^ The engine torque is 100 - 642 Nm (80 - 475 ft. lbs.).

Conditions for Setting the DTC
^ All of the Conditions for Running the DTC are met for 7 seconds.
^ The Gear Ratio is one of the following:
- Greater than 2.52 or less than 2.42
- Greater than 1.50 or less than 1.45
- Greater than 1.02 or less than 0.98
- Greater than 0.77 or less than 0.73
- Greater than 2.12 or less than 2.04

Action Taken When the DTC Sets
^ The PCM does not illuminate the Malfunction Indicator Lamp (MIL).
^ The PCM commands maximum line pressure.
^ The PCM freezes shift adapts.
^ The PCM stores DTC P0730 in PCM history.

Conditions for Clearing the DTC
^ A scan tool clears the DTC from PCM history.
^ The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without a non-emission-related diagnostic fault occurring.
^ The PCM cancels the DTC default actions when the fault no longer exists and the ignition switch is OFF long enough in order to power down the PCM.

Diagnostic Aids
^ First, diagnose and clear any engine DTCs that are present. Then inspect for any transmission DTCs that may have reset. If a DTC P0717 and a DTC P0730 are both present, diagnose DTC P0717 first.
^ Sticking or contaminated shift valves may cause an undefined gear ratio.
^ Refer to Shift Solenoid Valve State and Gear Ratio and Range Reference.
^ DTC P1870 detects an incorrect gear ratio in fourth gear with TCC applied.
^ DTC P0730 defaults to an elevated line pressure condition which may result in partial TCC apply. This may produce an idle surge that could stall the engine.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
3. This step tests the indicated range signal to the actual selected range. A faulty TFP manual valve position switch could set DTC P0730.
4. This step tests for proper ratios in each commanded gear state.