P1135 — Air/Fuel Ratio Sensor Heater Circuit Response (Bank 1 Sensor 1)
CAUTIONIs it safe to drive? Drive gently and get it looked at soon — it can worsen or fail inspection.
What P1135 means
This is a manufacturer-specific code — its meaning depends on the vehicle’s make (see below).
What P1135 means on specific makes
Toyota / Lexus / Scion CAUTION
The wideband A/F sensor's internal heater isn't warming the sensor fast enough, so the ECM can't trust its readings until the exhaust is hot. Extremely common Toyota/Lexus code; the upstream A/F sensor is a known wear item.
- Failed upstream A/F (wideband) sensor, Bank 1 Sensor 1 ($120-300 part)
- Blown EFI or A/F heater fuse
- Corroded sensor connector / wiring open
- Rare: ECM heater driver fault
Check first: Pull the A/F sensor connector and check heater element resistance and that the heater fuse has power; most cases are a worn-out sensor. If P1135 and P1155 set together, suspect a shared fuse/relay, not two dead sensors.
Source: autocodes.com/p1135_toyota.html, parts.olathetoyota.com/p1135-code, engine-codes.com