P0155

Tests 1 - 4:

Tests 5 - 7:

SYMPTOM
P0155-2/1 O2 SENSOR HEATER FAILURE

TEST NOTE
This symptom is diagnosed using the test P0135-1/1 O2 SENSOR HEATER FAILURE.

WHEN MONITORED
With battery voltage greater than 9 volts, at a cold start, ECT less than 147 °F, battery temperature sensor equal to or less than 27 °F, and engine at idle for at least 12 seconds.

SET CONDITION
O2 sensor voltage greater than 3 volts for 30 to 90 seconds.

POSSIBLE CAUSES
- O2 heater element
- O2 sensor heater ground circuit open
- O2 heater relay output circuit open
- Intermittent condition
- PCM