Buick Regal: DTC P0717, P07BF, or P07C0

Diagnostic Instructions

• Perform the Diagnostic System Check prior to using this diagnostic procedure: Refer to Diagnostic System Check - Vehicle
• Review the description of Strategy Based Diagnosis: Strategy Based Diagnosis
• An overview of each diagnostic category can be found here: Refer to Diagnostic Procedure Instructions

DTC Descriptor

DTC P0717

Input Speed Sensor Circuit No Signal

DTC P07BF

Input Speed Sensor Circuit Low Voltage

DTC P07C0

Input Speed Sensor Circuit High Voltage

Diagnostic Fault Information

Typical Scan Tool Data

Transmission ISS

Circuit/System Description

The sensor is an input to the control module K71. The input signal is used to determine the rotational speed of the component: Input Shaft

The control module uses this data, along with other data, to adjust or control the following:

• Torque Converter Clutch
• Transmission Shifting

Conditions for Running the DTC

P07BF, P07C0

• Ignition Voltage=10.2 to 15.5 V
• K71 Transmission Control Module= Communication Enabled

Frequency the DTC runs=Continuously - After the running conditions are met - For 2 s

Conditions for Setting the DTC

P0717

Transmission ISS=0 RPM & Transmission OSS=Greater than 0 RPM

P07BF

Transmission ISS=Invalid Signal Received - Short to Ground

P07C0

Transmission ISS=Invalid Signal Received - Short to Voltage

Actions Taken When the DTC Sets

DTCs listed in the DTC Descriptor Category=Type A DTC

• Autostart/Autostop=Disabled - If equipped
• Fail-Safe Mode=Active
• Learning=Disabled
• Torque Converter Clutch=Disabled
• Transmission OSS=Calculated

Conditions for Clearing the DTC

DTCs listed in the DTC Descriptor Category=Type A DTC

Reference Information

Schematic: Reference

Refer to Automatic Transmission Controls Wiring Schematics

Connector End View: Reference

Refer to Component Connector End View Index

Component View: Reference

Refer to Disassembled Views

Description and Operation

Refer to Transmission General Description

Electrical Information: Reference

• Refer to Circuit Testing
• Refer to Connector Repairs
• Refer to Testing for Intermittent Conditions and Poor Connections
• Refer to Wiring Repairs

DTC Type: Reference

Refer to Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool: Reference

Refer to Control Module: References

Circuit/System Verification

1. Engine - Running.

2. Transmission - Park.

3. Verify the scan tool parameter: Transmission ISS=Engine Speed.

• If not the specified state

Refer to Circuit/System Testing

• Go to next step: If the specified state

4. Transmission - Reverse.

5. Verify the scan tool parameter: Transmission ISS= 0.

• If not the specified state

Refer to Circuit/System Testing

• Go to next step: If the specified state

6. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Verify the DTC does not set.

• If the DTC sets

Refer to Circuit/System Testing

• Go to next step: If the DTC is not set

7. All OK.

Circuit/System Testing

NOTE: It may take up to 2 min for all vehicle systems to power down before an accurate ground or low reference circuit continuity test can be performed.

1. Ignition/Vehicle & All vehicle systems - Off

2. Remove the component:K71 Transmission Control Module

NOTE: Twisting or tilting of the transmission control module electrical connector while disconnecting may result in bent or misaligned electrical terminal pins.

3. Test for 4500000 to 5000000 ohms between the test points:Signal circuit terminal 18 & Low: Reference circuit terminal 17

• If not between 4500000 and 5000000 ohms

1. Remove the component:Control Valve Body Cover
2. Disconnect the electrical connector:B14C Transmission Input Shaft Speed Sensor
3. Test for less than 2 ohms between the test points:
   • Control circuit terminal 2@Component harness & Signal circuit terminal 18@Control module harness
   • Low: Reference circuit terminal 1@Component harness & Low: Reference circuit terminal 17@Control module harness
   • If 2 ohms or greater - Replace the component:Automatic Transmission Wiring Harness
   • If less than 2 ohms - Replace the component:B14C Transmission Input Shaft Speed Sensor

• Go to next step: If between 4500000 and 5000000 ohms

4. Test for infinite resistance between the test points:

• Signal circuit terminal 18 & Transmission Case
• Low: Reference circuit terminal 17 & Transmission Case
• If less than infinite resistance

1. Remove the component: Control Valve Body Cover
2. Disconnect the electrical connector:B14C Transmission Input Shaft Speed Sensor
3. Test for infinite resistance between the test points:
   • Signal circuit terminal 2@Component harness & Transmission Case
   • Low: Reference circuit terminal 1@Component harness & Transmission Case

• If less than infinite resistance - Replace the component: Automatic Transmission Wiring Harness.

  If less than infinite resistance - Replace the component:B14C Transmission Input Shaft Speed Sensor.

• Go to next step: If infinite resistance

5. Replace the component:K71 Transmission Control Module

Component Testing

1. Ignition/Vehicle - Off.

2. Disconnect the electrical connector:B14C Transmission Input Shaft Speed Sensor.

NOTE: The component's temperature should be 19 to 21ºC (66 to 70ºF) while testing.

3. Test for 4500000 to 5000000 ohms between the test points: Control terminal 2 & Low: Reference terminal 1.

• If not between 4500000 and 5000000 ohms

Replace the component:B14C Transmission Input Shaft Speed Sensor

• Go to next step: If between 4500000 and 5000000 ohms

4. Test for infinite resistance between the test points:Each terminal of the component & The component's housing.

• If less than infinite resistance

Replace the component:B14C Transmission Input Shaft Speed Sensor

• Go to next step: If infinite resistance

5. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair: Refer to Diagnostic Repair Verification

• Refer to Control Valve Body Replacement
• Refer to Input Speed Sensor Replacement
• Refer to Wiring Harness Wire Replacement - Automatic Transmission Wiring Harness
• For control module replacement, programming, and setup: Refer to Control Module: References

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