With Powertrain Control Module

CIRCUIT DESCRIPTION

The Powertrain Control Module (PCM) calculates a ratio based on the Automatic Transmission Input Shaft Speed (A/T 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 D DTC.

CONDITIONS FOR SETTING THE DTC

The following conditions are met for 7 seconds.

^ No MAP DTCs P0106, P0107, P0108.

^ No A/T ISS Sensor DTCs P0716 or P0717.

^ No OSS Sensor DTCs P0722 or P0723.

^ No Automatic Transmission Fluid Pressure Manual Valve Position Switch (TFP Val. Position Sw.) DTC P1810.

^ The Vehicle Speed is greater than 6.4 km/h (5 mph).

^ The APP Angle is greater than 25%.

^ The TFT is greater than 20°C (68°F).

^ System voltage is 9.0-16.0 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 3750 RPM.

^ The engine torque is 100-642 N.m (80-475 lb. ft).

^ 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.

^ DTC P0730 is stored in PCM history.


CONDTIONS 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

^ Sticking or contaminated shift valves may cause an undefined gear ratio.

^ Refer to the Shift Solenoid Valve State and Gear Ratio table.

^ First diagnose and clear any engine DTCs that are present. Then inspect for any transmission DTCs that may have reset. If a DTC P0717 Input Speed Sensor Circuit Low Input (Diesel) and a DTC P0730 are both present, diagnose DTC P0717 first.

^ DTC P1 870 detects an incorrect gear ratio in fourth gear with TCC applied.

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 Val. Position Sw. could set DTC P0730.

4. This step tests for proper ratios in each commanded gear state.