Pinpoint Test D : Output Shaft Speed (OSS) Sensor, Turbine Shaft Speed (TSS) Sensor And Intermediate Shaft Speed A (ISSA) Sensor
WARNING: This page is about a different variant/trim than selected.
- Refer to Transmission Controls - 8F57
for schematic and connector information.
Normal Operation and Fault Conditions
The OSS sensor is a Hall-effect type sensor that provides a signal to the PCM that changes in frequency as the rotating speed of the output shaft C1 varies. The PCM also compares the OSS sensor signal with the TSS sensor signal to determine the gear ratio provided by the rear planetary gearset. The PCM uses the OSS sensor signal as an input for its shift strategies and TCC operation. The PCM also uses the OSS sensor signal for transmission fault detection and diagnostics.
The 8F57 transmission uses an Intermediate Speed Sensor A (ISSA), hall-effect type sensor that provides a signal to the PCM. The signal it provides changes in frequency as the rotating speed of the component being monitored changes. The ISSA monitors the speed of the reaction sun gear.
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition PCM P0715:00 Input/Turbine Shaft Speed Sensor "A" Circuit: No Sub Type Information This DTC sets if the PCM detects an open or short to ground in the TSS sensor circuitry. PCM P0716:00 Input/Turbine Shaft Speed Sensor "A" Circuit Range/Performance: No Sub Type Information This DTC sets if the PCM detects too large of a sensor air gap, a TSS sensor fault or an undetected clutch fault. PCM P0717:00 Input/Turbine Shaft Speed Sensor "A" Circuit No Signal: No Sub Type Information This DTC sets relationally if DTCs P0715, P07BF, P07C0 are set, RESOLVE these DTCs first. PCM P0718:00 Input/Turbine Shaft Speed Sensor "A" Circuit Intermittent: No Sub Type Information This DTC sets if the PCM detects an intermittent circuit fault in the TSS circuit. PCM P07C0:00 Input/Turbine Shaft Speed Sensor "A" Circuit High: No Sub Type Information This DTC sets if the PCM detects an open circuit in the TSS sensor circuitry. PCM P0791:00 Intermediate Shaft Speed Sensor "A" Circuit: No Sub Type Information This DTC sets if the PCM detects an open or short to ground in the ISSA sensor circuitry. PCM P07C6:00 Intermediate Shaft Speed Sensor "A" Circuit High: No Sub Type Information This DTC sets relationally if DTCs P0715, P07BF, P07C0 are set, RESOLVE these DTCs first. PCM P0793:00 Intermediate Shaft Speed Sensor "A" Circuit No Signal: No Sub Type Information This DTC sets if the PCM detects an open or short to ground in the ISSA sensor circuitry. PCM P0794:00 Intermediate Shaft Speed Sensor "A" Circuit Intermittent: No Sub Type Information This DTC sets if the PCM detects an open circuit in the ISSA sensor circuitry. PCM P0720:00 Output Shaft Speed Sensor Circuit: No Sub Type Information This DTC sets if the PCM detects an open or short to ground in the OSS sensor circuitry. PCM P0721:00 Output Shaft Speed Sensor Circuit Range/Performance: No Sub Type Information This DTC sets if the PCM detects too large of a sensor air gap, a TSS sensor fault or an undetected clutch fault. PCM P0722:00 Output Shaft Speed Sensor Circuit No Signal: No Sub Type Information This DTC sets relationally if DTCs P0720, P077C or P077D are set, RESOLVE these DTCs first. PCM P0793:00 Intermediate Shaft Speed Sensor "A" Circuit No Signal: No Sub Type Information This DTC sets if the PCM detects an open or short to ground in the OSS sensor circuitry. PCM P077D:00 Output Shaft Speed Sensor Circuit High: No Sub Type Information This DTC sets relationally if DTCs P0720, P0721, P0793 are set, RESOLVE these DTCs first. Possible Sources
- Connectors damaged or pushed-out terminals, corrosion, loose wires or ground and missing or damaged seals
- TSS sensor
- Intermediate Speed Sensor A (ISSA)
- OSS sensor
- PCM
- D1 CHECK POWER CIRCUITS FOR VOLTAGE
- Ignition OFF.
- Disconnect: Transmission Vehicle Harness C1575
- Inspect the connector for damaged or pushed out terminals, corrosion, loose wires and missing or damaged seals.
- Ignition ON.
- For OSS sensor, measure:
Positive Lead Measurement / Action Negative Lead C1575-17 Ground
- Disconnect TSS sensor C143.
- Ignition ON.
- For TSS, sensor measure:
Positive Lead Measurement / Action Negative Lead C143-1 Ground
- Ignition ON.
- For ISSA, sensor measure:
Positive Lead Measurement / Action Negative Lead C1575-16 Ground
Is the voltage on the suspect circuit 8.2 to 9.5 volts?
Yes GO to D5 No GO to D2 - D2 CHECK THE SENSOR POWER CIRCUIT FOR A SHORT TO GROUND
- Disconnect: PCM C1551T
- Ignition OFF.
- For OSS sensor measure:
Positive Lead Measurement / Action Negative Lead C1575-17 Ground
- For TSS sensor measure:
Positive Lead Measurement / Action Negative Lead C143-1 Ground
- For ISSA sensor measure:
Positive Lead Measurement / Action Negative Lead C1575-16 Ground
Is the resistance on the suspect circuit greater than 10, 000 ohms?
Yes GO to D3 No INSPECT and REPAIR transmission vehicle harness sensor power circuit for a short to ground. - D3 CHECK THE SENSOR POWER CIRCUIT FOR AN OPEN
- Ignition ON.
Is the resistance on the suspect circuit less than 3 ohms?
Yes Refer to PCM Guided Routine . No REPAIR the circuit. - D4 CHECK THE SENSOR SIGNAL CIRCUIT FOR A SHORT TOGETHER WITH THE POWER CIRCUITS
- Ignition OFF.
- Disconnect: PCM C1551T (if not already disconnected).
- Disconnect: Transmission Vehicle Harness C1575 (if not already disconnected).
- Inspect the connector for damaged or pushed out terminals, corrosion, loose wires and missing or damaged seals.
- Measure:
OSS Sensor
Positive Lead Measurement / Action Negative Lead C1551T-51 C1551T-1 C1551T-51 C1551T-2 C1551T-51 C1551T-17 C1551T-51 C1551T-36 C1551T-51 C1551T-42 C1551T-51 C1551T-50 C1551T-51 C1551T-55 C1551T-51 C1551T-83
- Measure:
ISSA Sensor
Positive Lead Measurement / Action Negative Lead C1551T-37 C1551T-1 C1551T-37 C1551T-2 C1551T-37 C1551T-17 C1551T-37 C1551T-36 C1551T-37 C1551T-42 C1551T-37 C1551T-50 C1551T-37 C1551T-55 C1551T-37 C1551T-83 TSS Sensor
Positive Lead Measurement / Action Negative Lead C1551T-38 C1551T-1 C1551T-38 C1551T-2 C1551T-38 C1551T-17 C1551T-38 C1551T-36 C1551T-38 C1551T-42 C1551T-38 C1551T-50 C1551T-38 C1551T-55 C1551T-38 C1551T-83
Are the resistances on the suspect circuit greater than 10, 000 ohms?
Yes GO to D5 No REPAIR the circuit. - D5 CHECK THE SENSOR RETURN CIRCUIT FOR AN OPEN
- Ignition OFF.
- Inspect the connector for damaged or pushed out terminals, corrosion, loose wires and missing or damaged seals.
Is the resistance less than 3 ohms on the suspect circuit?
Yes GO to D6 No REPAIR the circuit for an open. - D6 CHECK THE SENSOR RETURN CIRCUIT FOR A SHORT TO GROUND
- Ignition OFF.
- For the OSS sensor, measure:
Positive Lead Measurement / Action Negative Lead C1575-8 Ground
- For the TSS sensor, measure:
Positive Lead Measurement / Action Negative Lead C143-1 Ground
- For the ISSA sensor, measure:
Positive Lead Measurement / Action Negative Lead C1575-6 Ground
Are the resistances on the suspect circuit greater than 10, 000 ohms?
Yes GO to D7 No REPAIR the circuit. - D7 CHECK THE INTERNAL HARNESS CIRCUITS FOR A SHORT TO POWER CIRCUITS
- REMOVE the main control.
- Disconnect OSS sensor C1107.
- Measure:
OSS Sensor
Positive Lead Measurement / Action Negative Lead
Transmission Harness Connector, component side, pin 8
Transmission Harness Connector, component side, pin 1
Transmission Harness Connector, component side, pin 8
Transmission Harness Connector, component side, pin 2
Transmission Harness Connector, component side, pin 8
Transmission Harness Connector, component side, pin 4
Transmission Harness Connector, component side, pin 8
Transmission Harness Connector, component side, pin 5
Transmission Harness Connector, component side, pin 8
Transmission Harness Connector, component side, pin 7
Transmission Harness Connector, component side, pin 8
Transmission Harness Connector, component side, pin 15
Transmission Harness Connector, component side, pin 8
Transmission Harness Connector, component side, pin 16
Transmission Harness Connector, component side, pin 8
Transmission Harness Connector, component side, pin 17
Transmission Harness Connector, component side, pin 8
Transmission Harness Connector, component side, pin 18
Are the resistances greater than 10, 000 ohms on the suspect circuit?
Yes GO to D8 No INSTALL a new transmission internal wiring harness. REFER to: Main Control Valve Body . - D8 CHECK THE INTERNAL HARNESS CIRCUITS FOR A SHORT TO POWER CIRCUITS
- REMOVE the main control.
- Disconnect OSS sensor C1107.
- Measure:
Intermediate Speed Sensor (ISS) A
Positive Lead Measurement / Action Negative Lead
Transmission Harness Connector, component side, pin 6
Transmission Harness Connector, component side, pin 1
Transmission Harness Connector, component side, pin 6
Transmission Harness Connector, component side, pin 2
Transmission Harness Connector, component side, pin 6
Transmission Harness Connector, component side, pin 4
Transmission Harness Connector, component side, pin 6
Transmission Harness Connector, component side, pin 5
Transmission Harness Connector, component side, pin 6
Transmission Harness Connector, component side, pin 7
Transmission Harness Connector, component side, pin 6
Transmission Harness Connector, component side, pin 15
Transmission Harness Connector, component side, pin 6
Transmission Harness Connector, component side, pin 16
Transmission Harness Connector, component side, pin 6
Transmission Harness Connector, component side, pin 17
Transmission Harness Connector, component side, pin 6
Transmission Harness Connector, component side, pin 18
Are the resistances greater than 10, 000 ohms on the suspect circuit?
Yes GO to A8 No INSTALL a new transmission internal wiring harness. REFER to: Main Control Valve Body . - D9 CHECK THE INTERNAL HARNESS POWER CIRCUITS FOR AN OPEN
- For the OSS sensor, measure:
Positive Lead Measurement / Action Negative Lead C1107-1
Transmission Harness Connector, component side, pin 17
- For the ISSA sensor, measure:
Positive Lead Measurement / Action Negative Lead C164-1
Transmission Harness Connector, component side, pin 18
Is the resistance on the suspect circuit less than 3 ohms?
Yes GO to D10 No INSTALL a new transmission internal wiring harness. REFER to: Main Control Valve Body . - For the OSS sensor, measure:
- D10 CHECK THE INTERNAL HARNESS CIRCUITS FOR A SHORT TO GROUND
- Ignition ON.
- For the OSS sensor, measure:
Positive Lead Measurement / Action Negative Lead
Transmission Harness Connector, component side, pin 17Ground
- For the ISSA sensor, measure:
Positive Lead Measurement / Action Negative Lead
Transmission Harness Connector, component side, pin 18Ground
Is the resistance on the suspect circuit greater than 10, 000 ohms?
Yes INSTALL a new sensor. REFER to: Transmission Range (TR) Sensor . No INSTALL a new transmission internal wiring harness. REFER to: Main Control Valve Body .