Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptor
DTC P215B: Vehicle Speed - Output Shaft Speed (OSS) CorrelationDiagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
OSS Supply Voltage | P0722, P0723 | P0722, P0723 | P0722, P0723 | P0721, P215B |
OSS Signal | P0722, P0723 | P0722, P0723 | P0722, P0723 | P0721, P215B |
Typical Scan Tool Data
Circuit | Normal Range | Open/High Resistance | Short to Voltage |
|---|---|---|---|
Operating Conditions: Engine running, normal operating temperature | |||
OSS Signal | 0-7,000 RPM | 0 RPM | 0 RPM |
OSS Supply Voltage | -- | 0 RPM | 0 RPM |
Circuit | Normal Range | Open/High Resistance | Short to Voltage |
|---|---|---|---|
Operating Conditions: Key ON, engine OFF or engine running, normal operating temperature | |||
OSS Signal | OK | OK | OK |
OSS Supply Voltage | OK | Out of Range | Out of Range |
8.3-9.3 Volts = OK, Any other voltage = Out of Range | |||
Circuit/System Description
The output speed sensor (OSS) assembly has 2 internal hall-effect type sensors, and is capable of sensing both speed and direction. The OSS mounts to the A/T rear case assembly and is connected to the control solenoid (w/body and TCM) valve assembly through a wire harness and connector. The sensor faces the hybrid direct, 2-3-4 clutch housing assembly machined teeth surface. The sensor receives 8.3-9.3 volts 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 machined surface of the output shaft.
The two sensor elements in the OSS assembly are spaced approximately 1/2 a tooth apart.
| • | When the vehicle is moving in a forward direction, sensor A detects a particular tooth before sensor B. |
| • | When the vehicle is moving in a reverse direction, sensor B detects a particular tooth before sensor A. |
The electronics in the sensor combine the two signals and send a signal with a different pulse width. This signal is interpreted by the TCM for speed and direction and is transmitted through the GMLAN circuits to the engine control module (ECM) and the hybrid powertrain control module (HPCM). The ECM, HPCM, and TCM compare the OSS signal with the ABS wheel speed sensor signal.
Conditions for Running the DTC
The vehicle speed is greater than 10 km/h (6 mph).
Conditions for Setting the DTC
ECM
The ECM OSS signal and the ABS wheel speed sensor signals differ by greater than 10 km/h (6 mph) for greater than 8 seconds.
HPCM
The ECM OSS signal and the ABS wheel speed sensor signals differ by greater than 10 km/h (6 mph) for greater than 10 seconds.
Action Taken When the DTC Sets
ECM
The ECM commands reduced engine power.
HPCM
The HPCM calculates the transmission output speed.
Conditions for Clearing the DTC
ECM
P215B is a Type A DTC.
HPCM
P215B is a Type B DTC.
Diagnostic Aids
| • | Vehicles equipped with a transfer case may set this DTC if the vehicle is moving while the transfer case is in the Neutral selection. Review the freeze frame records with a scan tool to identify if this DTC was set by the vehicle operator. Explain proper transfer case shifting procedures as necessary. |
| • | Inspect the OSS, harness, connector pins for metallic debris and output shaft machined face for damage or misalignment. Proper torque of the OSS mounting bolt is critical to proper OSS operation. |
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics
Connector End View Reference
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References for scan tool information.
Circuit/System Verification
- Inspect for the following mechanical conditions:
- Operate the vehicle at 16-32 km/h (10-20 mph) while observing the Transmission OSS and ABS wheel parameters on the scan tool.
Note: For vehicles equipped with a transfer case, review Diagnostic Aids.
| • | Loose, misaligned, OSS |
| • | Broken driveline components |
| ⇒ | The OSS and ABS wheel speed signal displays should not vary by greater than 10 km/h (6 mph). |
Circuit/System Testing
Note: For vehicles equipped with a transfer case, review Diagnostic Aids.
- Verify that OSS DTCs P0721, P0722, or P0723 are not set in the TCM.
- Verify that ABS DTCs C0035-C0050, C1207-C1210, C1221-C1228, C1232-C1235, C005A, C0245, or C122E are not set in the electronic brake control module (EBCM).
- Program the control module which set the DTC with the latest software version and retest for DTCs.
| ⇒ | If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle. |
| ⇒ | If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle. |
| ⇒ | If the DTC resets, replace the control module which set the DTC. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Perform the Automatic Transmission Wiring Harness and Output Speed Sensor Removal and Automatic Transmission Wiring Harness and Output Speed Sensor Installation for OSS replacement. |
| • | Control Module References for ECM or HPCM replacement, setup, and programming. |
