6L45/6L50/6L80/6L90 - Automatic Transmission
DTC P150A or P150B
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 Descriptor
DTC P150A
-
Transmission Output Speed Signal Circuit
DTC P150B
-
Transmission Output Speed Sensor Circuit Intermittent
Circuit/System Description
The vehicle speed sensor (VSS), also called the output shaft speed sensor (OSS) creates an AC voltage as the rotor teeth pass through the magnetic field of the sensor. The transmission control module (TCM) converts the AC voltage into a vehicle speed signal, which is used to determine shift timing and torque converter clutch (TCC) scheduling. The TCM also provides a replicated transmission output speed signal (RTOSS) to the engine control module (ECM).
Conditions for Running the DTC
P150A
* The ignition voltage is greater than 8.6 volts.
* The engine speed is greater than 500 RPM.
* The transmission output speed is greater than 1200 RPM.
P150B
* The ignition voltage is greater than 18 volts.
* The engine speed is greater than 500 RPM.
* The transmission output speed is greater than 1200 RPM.
Conditions for Setting the DTC
P150A
The replicated output speed is 60 RPM or less for 4.5 seconds.
P150B
The change in replicated output speed is 350 RPM or greater for 3.25 seconds.
Conditions for Clearing the DTC
P150A
* DTC P150A is a Type B DTC.
* The replicated output speed is 150 RPM or greater for at least 3 seconds.
P150B
* DTC P150B is a Type B DTC.
* Transmission output speed is 150 RPM or greater for at least 2 seconds.
* The change in transmission output speed is 150 RPM or less for at least 3 seconds.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics 6L45/6L50/6L80/6L90 - Automatic Transmission
Connector End View Reference
* Component Connector End Views 1-2 Shift Solenoid (SS) Valve (M30)
* Inline Harness Connector End Views X100
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
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
Circuit/System Verification
1. If there are any other engine or transmission related DTCs set, diagnose those DTCs first.
2. Road test the vehicle from zero to 64 km/h (40 MPH). With a scan tool monitor the TCM output speed sensor and the ECM speed signal parameter values. Both parameters values should be within 3-4 km/h (2-3 MPH) of each other.
• If both parameter values are not within the specified range
Refer to Circuit/System Testing below.
• If both parameter values are within the specified range
3. 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
1. Ignition OFF, disconnect the ECM connector X1.
2. Ignition ON, test for 4.8-5.2 volts on the output speed sensor signal circuit terminal 71 and ground.
• If not within the specified range
Test the output speed sensor circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the TCM.
• If within the specified range
3. If all circuits test normal, replace the ECM.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
Control Module References Control Module References for ECM replacement, programming, and setup.