P0730

Diagnostic Chart:

CIRCUIT DESCRIPTION

The Powertrain Control Module (PCM) calculates gear ratio based on data from the Automatic Transmission Input (Shaft) and Output (Shaft) Speed sensors. The PCM compares the known transmission gear ratio to a calculated ratio for each gear range selected.

DTC P0730 sets if the steady state adapts are at their maximum, and the PCM detects an incorrect gear ratio because of excessive slip within the transmission. DTC P0730 is a Type C DTC.

CONDITIONS FOR SETTING THE DTC

^ No MAF DTCs P0101, P0102 or P0103

^ No TP DTCs P0121, P0122 or P0123.

^ No VSS DTCs P0502 or P0503.

^ No Automatic Transmission Input (Shaft) Speed Sensor (A/T ISS) DTCs P0716 or P0717.

^ No 1-2 shift solenoid valve electrical DTC P0753.

^ No 2-3 shift solenoid valve electrical DTC P0758.

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

^ The engine run time is greater than 5 seconds.

^ The engine is not in fuel cut off.

^ The automatic transmission range switch Is not indicating park or neutral.

^ The time since the gear select lever change is greater than 3 seconds.

^ The throttle angle is greater than 15.7 degrees.

^ The vehicle speed is greater than 11 km/h (7 mph).

^ The transmission fluid temperature is greater than 20°C (68°F).

^ Delivered torque is greater than 135 N.m (100 lb. ft).

^ At least one steady state adapt cell is at maximum.

^ All of the following failure criteria are true for 4 seconds:

- First gear ratio is less than 2.87 or greater than 3.11.

- Second gear ratio is less than 1.54 or greater than 1.71.

- Third gear ratio is less than 0.95 or greater than 1.05.

- Fourth gear ratio is less than 0.65 or greater than 0.71.

- Reverse gear ratio is less than 2.02 or greater than 2.23.

ACTION TAKEN WHEN THE DTC SETS

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

^ SERVICE VEHICLE SOON displays on the Driver Information Center (DIC).

^ The PCM commands maximum line pressure.

^ The PCM disables steady state adapts.

^ The PCM disables upshift adapts.

^ The PCM disables garage shift adapts.

^ DTC P0730 is stored in the PCM history.

CONDITIONS FOR CLEARING THE DIC/DTC

^ The PCM turns OFF the DIC after three consecutive trips without a failure reported.

^ The PCM sees a correct gear ratio in each gear range for 4 seconds.

^ 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

^ Ensure that the vehicle's final drive ratio matches PROM calibration.

^ Refer to the Range Reference table.

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

TEST DESCRIPTION

The numbers below refer to the steps on the Diagnostic Table.

2. This step verifies that you inspected the transmission fluid and that the fluid is at the proper level. An underfilled transmission could result in insufficient hydraulic line pressure causing the transmission to slip.

3. This step inspects for additional DTCs. If a VSS or A/T ISS DTC is set, refer to those DTC tables first.

7. This step replaces the pressure control solenoid valve which caused the high line pressure.

9. This step inspects and either replaces or repairs the faulty components that caused the low line pressure.

IMPORTANT: When driving the vehicle in reverse, the command gear will be first.

10. This step inspects the reverse clutch and the b/reverse band for slippage when the vehicle is placed in reverse and the ratio is too high (2.22).

11. This step inspects the valve body for hydraulic failure when the vehicle was placed in reverse (2.02).