P2489Exhaust Gas Temperature Sensor Circuit Intermittent/Erratic (Bank 2 Sensor 5)
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P2489 points to an unsteady signal from the fifth exhaust probe on bank 2: the value stays within its electrical limits but jumps or drops out briefly. This code is not documented by any manufacturer, as no public layout carries five probes per bank on a twin-bank engine. For the bank 1 position GM shows the method under P2484: samples every 100 ms are compared, and in 2025 a step above 100 °C in 12 of 25 samples, valid only between 140 and 1070 °C, sets a Type B fault. CARB requires monitoring of inputs for erratic behaviour where it affects emissions. Such faults usually come from loose terminals or a harness that touches hot parts, so a careful check of routing and clips pays off.
- What you may notice
- Warning lamp coming and going
- Jumping value in live data
- Likely causes
- LikelyLoose terminal in the connector
- PossibleHarness touching hot exhaust parts
- RareInternal crack in the probe
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €40 – €350
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.