Car Diagnostics

TPMS warning light on (tyre pressure)

Yellow exclamation tyre icon — low pressure or a faulty sensor. How to tell them apart.

TPMS light can mean two things: (1) genuinely low pressure in one or more tyres — check with a gauge; (2) a faulty sensor or TPMS module malfunction — system error, actual pressure may be fine.

Blinking TPMS light usually = sensor fault or dead sensor battery (sensors last 5-10 years). Solid light = low pressure in one or more tyres.

OBD-II: C/B TPMS codes are usually in the Body Control Module. Modern cars expose a Live TPMS PID showing pressure at each wheel in PSI or bar — ideal for diagnosis without leaving the car.

First diagnostic steps

  1. Check all 4 tyres (and spare) with a pressure gauge
  2. If pressure is OK — read live TPMS PID (shows pressure and temperature per sensor)
  3. Read C-codes from BCM or TPMS module
  4. If a sensor doesn't respond after inflating and driving 10+ min — likely a dead sensor battery
  5. After tyre changes or rotation, perform the TPMS relearn procedure

Likely fault codes

C0750C0755C0760C0765C0775

Click a code for detailed description, causes, and diagnostic plan.