P046A
Catalyst Temperature Sensor 1/2 Correlation (Bank 1)
Catalyst temperature sensors 1 and 2 on bank 1 disagree by more than the allowed tolerance over a drive cycle.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Symptoms
- Check engine light on
- Failed emissions inspection
- Possibly slightly increased fuel consumption
- Sulfur (rotten egg) smell from exhaust under load
Common causes
Ordered by how often each turns out to be the cause.
- One sensor driftsCommon
Parts involved
- Exhaust Temperature Sensor
P046A is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.