P1149

DTC P1149: A/F Sensor (Sensor 1) Range/Performance Problem

NOTE: If some of the DTCs listed below are stored at the same time as DTC P1149 or P1165, troubleshoot those DTCs first, then troubleshoot DTC P1149 or P1165.
P0137, P0138: Secondary HO2S (Sensor 2)
P0141: Secondary HO2S (Sensor 2) heater

1. Reset the ECM/PCM.
2. Start the engine. Hold the engine speed at 3,000 rpm with no load (in Park or neutral) until the radiator fan comes on.
3. Test-drive under the following conditions:

- 55 mph (89 km/h) steady speed
- CVT in D position (M/T in 5th gear)
- Until the A/F monitor readiness code is set to complete or Temporary DTC P1149 (P1165) comes on

4. Check for a Temporary DTC with the HDS or a scan tool.

Is Temporary DTC P1149 (P1165) indicated?

YES - Replace the A/F sensor (Sensor 1).

NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the A/F sensor relay, at the A/F sensor (Sensor 1) and at the ECM/PCM.