P0730

DTC P0730 (Gas)








Circuit Description
The powertrain control module (PCM) calculates a gear 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 sensor DTCs P0106, P0107, or P0108.
- No TP sensor DTCs P1120 or P1 220.
- No VSS DTCs P0502 or P0503.
- No ISS DTCs P0716 or P0717.
- No TFP manual valve position switch DTC P1810.
- The system voltage is 8 - 18 volts.
- The vehicle speed is greater than 8 km/h (5 mph).
- The TP angle is greater than 15 percent.
- The transmission fluid temperature is greater than 20°C (68°F).
- No gear range change for greater than 6 seconds.
- The engine torque is 110 Nm (80 ft. lbs.) to 881 Nm (650 ft. lbs.).
- The engine is running for 7 seconds and not in fuel cutoff.

Conditions for Setting the DTC
The Gear Ratio is one of the following for 10 seconds:
- Greater than 2.51 or less than 2.44
- Greater than 1.50 or less than 1.44
- Greater than 1.03 or less than 0.97
- Greater than 2.12 or less than 2.05

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 records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Failure Records.
- 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
- 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.
- A false or incorrect OSS or ISS signal can set DTC P0730.
- DTC P1870 detects an incorrect gear ratio in fourth gear with TCC applied.
- Inspect for any improperly installed after-market equipment.
- Sticking or contamination of shift valves may cause intermittent incorrect gear ratios.
- Refer to the Shift Solenoid Valve State and Gear Ratio.

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 correct ratios in each commanded gear.