P0753

Diagnostic Chart:

Electrical Diagram:

CIRCUIT DESCRIPTION
The 1-2 shift solenoid valve controls transmission fluid to the 1-2 shift valve. Ignition voltage is provided to the solenoid. The Powertrain Control Module's (PCM) Output Driver Module (ODM) provides the ground. When the 1-2 shift solenoid valve is commanded ON, the PCM senses 0 volts. When the 1-2 shift solenoid valve is commanded OFF, the PCM senses ignition voltage.

If the PCM detects voltage limits that do not meet the calibration, then DTC P0753 sets. DTC P0753 is a Type A DTC.

CONDITIONS FOR SETTING THE DTC
^ No ODM DTC P1650.
^ The engine run time is greater than 5 seconds.
^ The PCM detects an open, a short to ground, or a short to power on the 1-2 shift solenoid valve circuits within 5 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ The PCM illuminates the Malfunction Indicator Lamp (MIL).
^ SERVICE ENGINE SOON, SERVICE TRANSMISSION displays on the Driver Information Center (DIC).
^ The PCM commands 2nd gear.
^ The PCM commands default line pressure.
^ The PCM inhibits Torque Converter Clutch (TCC) engagement.
^ The PCM disables steady state adapts.
^ The PCM disables garage shift adapts. DTC P0753 is stored in the PCM history.

CONDITIONS FOR CLEARING THE MIL/DTC
^ The PCM turns OFF the MIL after three consecutive trips without a failure reported.
^ 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
^ Inspect the wiring at the PCM, the transmission 20-way connector, the 1-2 shift solenoid valve 2-way connector, and all other circuit connecting points for the following conditions:
- A bent terminal.
- A backed out terminal.
- A damaged terminal.
- Poor terminal tension.
- A chafed wire.
- A broken wire inside the insulation.
- Moisture intrusion.
^ When diagnosing for an intermittent short or open, massage the wiring harness while watching the test equipment for a change.
^ Refer to Shift Solenoid Valve State and Gear Ratio table.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table.
6. This step verifies that the 1-2 Shift Solenoid Valve is operating and that an intermittent problem may have set the DTC.
7. This step isolates the automatic transmission wiring harness so that you can diagnose the engine wiring harness.
9. This step isolates circuit 1222 for an open.
11. This step isolates circuit 1222 of the engine wiring harness for a short to power.
13. This step isolates the engine wiring harness so that you may diagnose the automatic transmission wiring harness.
16. This step measures for a short to ground in circuit 1222.