P1178

System/Component
Oxygen Sensor (2) (upstream Cat.-system) cylinder 1-3

Fault Code
P1178 Switching Time

Fault Type
Plausibility Yes
Signal No
Minimum Threshold No
Maximum Threshold No

Monitoring Method
time range check

Signal Type
ECM internal signal/value computation or comparison

Operating Range
(model) > 353°C
> 628°C

Time Length and Frequency for Monitoring/Diagnosis
20 sec/once per trip

Criteria for storing fault code
fault during 2 trips

Criteria for illuminating the MIL
fault during 2 trips and end of 2nd trip

Criteria used for determining out of range values and input component rationality check
UBATT No
Ground No
Disconnect No

Electronic Control Module (ECM)
Comparison of each measured switching time (lean to rich and rich to lean) to predetermined maximum map values which depends on engine air mass flow.
If sum (measured times) during 115 lambda controller cycles is > than sum (max. map values) a fault will be detected.

max. map values
air mass [kg/h] 10 20 40 60 180 260
lean-rich[ms] 365 260 180 145 105 210
rich-lean[ms] 935 570 380 285 150 170