2017 GMC Canyon
Mileage
68,768
Service Date
7/10/2026
Services Performed
- PRELIMINARY SCAN: Connected scan tool and performed complete vehicle network code scan. Located code P0700 (Transmission Control Module Requested MIL Illumination) stored active in the Engine Control Module (ECM). Communicated with the Transmission Control Module (TCM) and recovered code P0711 (Transmission Fluid Temperature Sensor Performance) stored active. DATA STREAM ANALYSIS: Monitored live TFT (Transmission Fluid Temperature) data via scan tool from a cold start. Noted the TFT reading was flatlined/stuck at an unrealistic value or failing to rise logically alongside engine coolant temperature during an extended test drive, confirming a sensor performance failure. VEHICLE INSPECTION: Elevated vehicle on hoist to inspect external transmission wiring harness, 16-way connector interface, and ground paths. External harness and pins are clean, tight, and free of physical damage or external corrosion. CIRCUIT TESTING: Checked resistance across the signal and return circuits at the transmission external case connector. Circuit integrity to the internal harness interface verified good, isolating the fault to an internal performance failure of the sensor component itself.
- Drain transmission fluid and remove the oil pan. Inspect the pan magnet for any abnormal friction material or metal debris to verify baseline mechanical transmission health.2.Remove Internal Valve Body Harness:Delicate plastic clips.Carefully disconnect the internal solenoids and release the pass-through connector lock to remove the failed internal wiring harness assembly containing the integrated TFT sensor.3.Install New OEM Harness Assembly:GM Part #24298757 or superseding number.Install a brand-new OEM internal transmission wiring harness assembly. Route the wiring carefully into the factory retaining channels and securely clip all solenoid connections.4.Reassemble, Service, and Road Test:New pan gasket and filter.Install a new transmission fluid filter and pan gasket. Reinstall the oil pan and torque to factory specifications. Refill with fresh Dexron VI / Mobil 1 LV ATF HP fluid to the correct operating level. Clear all diagnostic trouble codes and perform an extended road test to verify normal shifting strategy and stable TFT data tracking.
- AUTOMATIC TRANSMISSION FLUID – Drain & Refill – Automatic Trans – [Includes: Confirm Fluid temperature for level check.] – [Includes: Check Fluid level and condition.]
- ROT. TIRES
SHELLY S. gave our service a 5 star review on 7/11/2026
