Check engine codes C0775?

2008 CHEVROLET EQUINOX
215,000 MILES • AUTOMATIC
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FARR_2007
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I have attached pics of the codes I’m getting along with a couple short live data reading videos and one with some flashing red issues on the scanner
Sep 6, 2026 at 8:20 PM
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STRAILER
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Here is what the screens indicate:

1. P0507 — Idle speed higher than expected: This is the Check Engine light fault. Look for a vacuum leak, split intake duct, leaking PCV or EVAP-purge circuit, dirty/sticking throttle body, or incorrect throttle/idle data. A smoke test of the intake is the best starting point. Do not replace the throttle body until vacuum leaks have been eliminated.

2. C0775 — TPMS sensors not learned: This is stored in the Remote Control Door Lock Receiver because the tire-pressure sensor identification/relearn procedure was not completed successfully. Check tire pressures and perform a complete four-wheel TPMS relearn. It is unrelated to engine performance.

3. B0081-0F — Passenger-presence system fault: This concerns the front-passenger occupant-detection system. Inspect the wiring and connectors beneath the passenger seat for looseness, corrosion, or damage, but disconnect the battery and follow the SRS disabling procedure before touching them. Do not measure airbag circuits with an ordinary meter. The passenger-presence system may require calibration or component diagnosis using a GM-capable scanner. Left- and right-rear wheel-speed sensor failures: Watch all four wheel-speed readings while driving slowly. If both rear readings drop out together, inspect shared wiring/connectors and power or ground circuits before replacing both hubs. If only one reading is erratic, inspect that sensor, its harness, connector, reluctor, and wheel-bearing assembly.

Battery-voltage failure: This could be a history code from a weak or disconnected battery. The approximately 14.2–14.4 volts visible in the photographs is normal charging voltage with the engine running. Load-test the battery and then clear this code to see whether it returns.

Does the engine crank over? If not I would replace the battery, then clear the codes and let me know what happens.
Sep 7, 2026 at 9:52 AM
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FARR_2007
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There is a tire relearn option on the scanner but how long does these usually take I have never done one before
Sep 7, 2026 at 9:58 AM
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STRAILER
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These are separate issues, please start new questions for the B0081 and P0507, we will handle the C0775 on this thread. A tire-pressure sensor relearn on this vehicle usually takes about five minutes if all four sensors respond correctly. Once the relearn mode is activated, begin at the left-front tire, then proceed clockwise:

Left front
Right front
Right rear
Left rear

Use the scanner’s TPMS activation tool at each valve stem and wait for the horn chirp before moving to the next tire. The horn should chirp twice after the last sensor, confirming completion.

The system normally allows about two minutes for the first sensor and five minutes total. If one tire will not trigger, its sensor battery may be dead or the scanner may only initiate relearn mode and require a separate TPMS activation tool. Afterward, clear code C0775, drive the vehicle, and see whether it returns.
Sep 8, 2026 at 9:20 AM
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