Pinpoint Test F : OSS Sensor, TSS And ISSA Sensor Performance DTC Faults
- Refer to Transmission Controls - 8F57
for schematic and connector information.
Normal Operation and Fault Conditions
ISSA Sensor
The Intermediate Speed Sensor A (ISSA) is a Hall-effect type sensor that provides a signal to the PCM that changes in frequency as the rotating speed of the component being monitored changes. ISSA monitors the speed of sun gear 3.
TSS Sensor The TSS sensor is a Hall-effect type sensor that provides a signal to the PCM that changes in frequency as the rotating speed of the planetary carrier No. 2 varies.
OSS Sensor 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.
DTC Fault Trigger Conditions
DTC Description Fault Trigger Condition 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 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 OSS sensor fault or an undetected clutch fault. PCM P0792:00 Intermediate Shaft Speed Sensor "A" Circuit Range/Performance: No Sub Type Information This DTC sets if the PCM detects an intermittent circuit fault in the ISSA sensor circuit. Possible Sources
- Connectors damaged or pushed-out terminals, corrosion, loose wires or ground and missing or damaged seals
- Loose sensor
- Intermittent short to ground
- F1 CHECK FOR DTCS
- Using a diagnostic scan tool, perform the PCM self-test.
- If any other speed sensor DTCs are present resolve them first.
Are DTCs P0716, P0721, P0792, P2746 present?
Yes For DTC P0716, GO to F2 For DTC P0721, GO to F3 For DTC P0792, GO to F4 No For all other DTCs refer to the DTC chart. Otherwise the fault may be intermittent. - F2 CHECK TSS SENSOR
- If any other TSS sensor DTCs are present resolve them first. If DTC P0716 is present alone, INSPECT the TSS electrical connections for loose connections. Confirm the TSS sensor is not loose. INSPECT TSS tone wheel (part of No. 2 carrier) for damage.
Were any issues found?
Yes REPAIR wiring connections or INSTALL new parts as necessary. No INSTALL a new TSS sensor. REFER to: Turbine Shaft Speed (TSS) Sensor . - F3 CHECK OSS SENSOR
- If any other OSS sensor DTCs are present resolve them first. If DTC P0721 is present alone, INSPECT the OSS electrical connections for loose connections. Visually check the air gap and confirm the OSS sensor is not loose. INSPECT OSS tone wheel (part of No. 4 carrier) for damage.
Were any issues found?
Yes REPAIR wiring connections or INSTALL new parts as necessary. No INSTALL a new OSS sensor. REFER to: Output Shaft Speed (OSS) Sensor . - F4 CHECK INTERMEDIATE SHAFT SPEED SENSOR (ISSA) "A"
- If any other ISSA sensor DTCs are present resolve them first. If DTC P0792 is present alone, INSPECT the ISSA electrical connections for loose connections. Visually check the air gap and confirm the ISSA sensor is not loose. INSPECT ISSA trigger wheel (part of the No. 1 ring gear) for damage.
Were any issues found?
Yes REPAIR wiring connections or INSTALL new parts as necessary. No INSTALL a new ISSA. REFER to: Transmission .