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P077D




DTC P0722, P0723, P077C, or P077D

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0722

-
Output Speed Sensor Circuit No Signal

DTC P0723

-
Output Speed Sensor Intermittent

DTC P077C

-
Output Speed Sensor Circuit Low Voltage

DTC P077D

-
Output Speed Sensor Circuit High Voltage

Diagnostic Fault Information






Typical Scan Tool Data










Circuit/System Description

The output speed sensor (OSS) is a hall-effect type sensor. The OSS mounts to the automatic transmission case assembly and connects to the control solenoid valve assembly through a 2-wire harness and connector. The sensor faces the park gear teeth. The sensor receives battery voltage on the OSS supply voltage circuit from the transmission control module (TCM). As the output shaft rotates, the sensor produces a signal frequency based on the park gear teeth. This signal is transmitted through the OSS signal circuit to the TCM. The TCM uses the OSS signal to determine line pressure, transmission shift patterns, vehicle speed and gear ratio.

Conditions for Running the DTC

P0722

* DTC P0101, P0102, P0103, P0121, P0122, P0123, P0716, P0717, P0722, or P0723 is not set.

* Ignition voltage is 9.0 volts or greater.

* Engine speed is greater than 400 RPM for 5 seconds.

* Engine torque signal is valid.

* Throttle position signal is valid.

* Transmission input speed is between 1,000-8,191 RPM.

* Calculated throttle position is 8 percent or greater.

* Engine torque is greater than 30 Nm (22 lb ft).

* TFT is greater than -40°C (-40°F).

P0723

* DTC P0101, P0102, P0103, P0121, P0122, P0123, P0723, P0973, P0974, P0976, or P0977 is not set.

* Ignition voltage is 9.0 volts or greater.

* Greater than 5 seconds since last range change.

* Engine speed is greater than 400 RPM for 5 seconds.

P077C

* DTC P077D is not set.

* Ignition voltage is 9.0 volts or greater.

P077D

* DTC P077C is not set.

* Ignition voltage is 9.0 volts or greater.

Conditions for Setting the DTC

P0722

Transmission output speed is 35 RPM or less for 5 seconds.

P0723

* Transmission output speed is 105 RPM or greater.

* Transmission output speed drops 1,000 RPM for greater than 3 seconds and does not recover.

P077C

Transmission OSS analog signal voltage is 0.25 volts or less for 4 seconds.

P077D

Transmission OSS analog signal voltage is 4.75 volts or greater for 4 seconds.

Action Taken When the DTC Sets

P0722

* DTC P0722 is a Type A DTC.

* TCM freezes transmission adaptive functions.

* TCM commands maximum line pressure.

* TCM forces the torque converter clutch (TCC) OFF.

* TCM Enables torque management.

* TCM limits the transmission to reverse and 2nd gear.

* TCM inhibits neutral idle.

* TCM inhibits Tap-Up/Tap-Down functions.

* TCM inhibits manual up, manual down shifts with the shift selector.

P0723, P077C or P077D

* DTCs P0723, P077C, and P077D are Type A DTCs.

* TCM freezes transmission adaptive functions.

* TCM forces TCC OFF.

* TCM commands the high side driver OFF.

* TCM commands maximum line pressure.

* TCM enables torque management.

* TCM limits the transmission to reverse and 5th gear.

* TCM inhibits neutral idle.

* TCM inhibits Tap-Up/Tap-Down functions.

* TCM inhibits manual up, manual down shifts with the shift selector.

Conditions for Clearing the DIC/DTC

DTCs P0722, P0723, P077C, and P077D are Type A DTCs.

Diagnostic Aids

Inspect the OSS, harness, and connector for metallic debris and proper alignment of the OSS with the park gear. Proper torque of the OSS mounting bolt is critical to proper OSS operation.

Reference Information

Schematic Reference

Automatic Transmission Controls Schematics (MH8) Electrical Diagrams

Connector End View Reference

* Component Connector End Views Sunshade - Left (DH6)

* Inline Harness Connector End Views Power Steering Control Harness to Forward Lamp Harness (NJ1)

Description and Operation

* Transmission General Description Transmission General Description

* Transmission Component and System Description Transmission Component and System Description

* Electronic Component Description Electronic Component Description for output speed sensor (OSS)

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References Control Module References for scan tool information

Special Tools

* DT-48616-10 - Adapter Harness

* EL 38522 - Variable Signal Generator

For equivalent regional tools, refer to Special Tools 6T30/6T40/6T45/6T50 - Automatic Transmission.

Circuit/System Verification

1. Ignition ON, verify with a scan tool the transmission ISS/OSS Supply Voltage test status parameter displays OK.

• If the parameter value displays Fault or Malfunction

Refer to Circuit/System Testing below.

• If the parameter value displays OK

2. Operate the vehicle at 16-32 km/h (10-20 mph) while observing the Transmission OSS parameter on the scan tool. Verify the Transmission OSS parameter varies with the vehicle speed and there are no spikes or dropouts.

• If the parameter value does not vary with vehicle speed or has spikes or dropouts

Refer to Circuit/System Testing below.

• If the parameter value varies with vehicle speed and there are no spikes or dropouts

3. Perform the Road Test 6T30/6T40/6T45/6T50 - Automatic Transmission. Verify DTC P0722, P0723, P077C, or P077D did not set.

• If DTC P0722, P0723, P077C, or P077D set

Refer to Circuit/System Testing below.

• If DTC P0722, P0723, P077C, or P077D did not set

4. After performing the above steps, verify that the DTC does not reset by operating the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions you observe from the Freeze Frame/Failure Records data. If the vehicle passes the Circuit/System Verification procedure, then STOP. Do not perform the Circuit/System Testing or Component Testing as this may result in an unnecessary part replacement. Refer to Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections.

Circuit/System Testing

Note:
You must perform the Circuit/System Verification first.

1. Ignition OFF, remove the Q8 control solenoid valve assembly. Refer to Control Solenoid Valve and Transmission Control Module Assembly Replacement Service and Repair.

2. Connect the DT-48616-10 - harnessbetween the vehicle wire harness X1 14-way transmission electrical connector, and the Q8 control solenoid valve assembly.

3. Ignition ON.

4. Test for 11-13 volts between the OSS voltage circuit terminal B on the Q8 control solenoid valve assembly X4 connector and ground.

• If not between 11-13 volts

Replace the Q8 control solenoid valve assembly.

• If between 11-13 volts

5. Perform the Control Solenoid Valve and Transmission Control Module Assembly Input Shaft Speed/Output Shaft Speed Input Test Control Solenoid Valve and Transmission Control Module Assembly Input Shaft Speed/Output Shaft Speed Input Test.

• If the Q8 control solenoid valve assembly does not pass the Input Shaft Speed/Output Shaft Speed Input Test

Replace the Q8 control solenoid valve assembly.

• If the Q8 control solenoid valve assembly passes the Input Shaft Speed/Output Shaft Speed Input Test

6. Inspect the park gear and B14A transmission output speed sensor alignment with the gear.

• If the park gear is damaged or there is improper alignment

Repair or replace as necessary.

• If the park gear is not damaged and alignment checks OK

7. Replace the B14A transmission output speed sensor.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

Note:
Before replacing the TCM, perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection Control Solenoid Valve and Transmission Control Module Assembly Inspection.

* Refer to Control Module References Control Module References for control solenoid valve assembly replacement, programming and setup.

* Perform the Transmission Adaptive Values Learn Transmission Adaptive Values Learn following all transmission related repairs.

* Perform the Input and Output Speed Sensor Removal 4. Input and Output Speed Sensor Removal and the Input and Output Speed Sensor Installation 42. Input and Output Speed Sensor Installation.

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