DTC Advanced Diagnostics: P0134
DTC P0134:Air/Fuel Ratio (A/F) Sensor (Sensor 1) Heater System Malfunction (Engine Type: K24W1)

General Description

The air/fuel ratio (A/F) sensor (sensor 1) is activated by warming the element with a heater and by maintaining a steady high temperature to accurately calculate the air/fuel ratio. If the heater does not properly heat the element, the A/F sensor (sensor 1) does not activate, and the exhaust emissions deteriorate. The powertrain control module (PCM) monitors the A/F sensor (sensor 1) internal resistance.
1.
When the A/F sensor (sensor 1) does not activate for a set time after the A/F sensor (sensor 1) heater is turned on (with high A/F sensor (sensor 1) internal resistance), a malfunction of the A/F sensor (sensor 1) heater is detected, and a DTC is stored.
2.
When the A/F sensor (sensor 1) heater cycles ON and OFF for a set time, and the resistance remains high when the heater is ON, a malfunction of the A/F sensor (sensor 1) heater is detected, and a DTC is stored.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status
Execution
Continuous
Sequence
None
Duration*1
40 seconds or more
Duration*2
90 seconds or more
DTC Type
Two drive cycles, MIL on
OBD Status
PASSED/FAILED/NOT COMPLETED (STILL TESTING)
*1: KA, KC, KL models

*2: KX model

Enable Conditions
Condition
Minimum
Maximum
Battery voltage [BATTERY]
10.5 V
Fuel feedback
Other than during fuel cut-off operation
No active DTCs set (prevents monitor from running)*3
P0135, P0300, P0301, P0302, P0303, P0304, P0351, P0352, P0353, P0354, P1157, P1172, P2195, P2238, P2252
No active DTCs set (prevents monitor from running)*4
P0122, P0123, P0135, P0222, P0223, P0300, P0301, P0302, P0303, P0304, P0351, P0352, P0353, P0354, P060A, P1157, P1172, P1659, P2101, P2118, P2122, P2123, P2127, P2128, P2135, P2138, P2176, P2195, P2238, P2252
*3: 2013 model

*4: 2014 model on and after

[ ]: HDS Parameter

Malfunction Threshold (KA, KC, KL Models)
Malfunction determination 1 - From start up
The A/F sensor (sensor 1) internal resistance value [AF SENSOR IMPEDANCE] is 120 ? or more for at least 40 seconds right after the engine starts.
Malfunction determination 2 - Hot
The A/F sensor (sensor 1) internal resistance value [AF SENSOR IMPEDANCE] is 250 ? or more for at least 1.0 second.

Malfunction Threshold (KX Model)
Malfunction determination 1 - From start up
The A/F sensor (sensor 1) internal resistance value [AF SENSOR IMPEDANCE] is 120 ? or more for at least 90 seconds right after the engine starts.
Malfunction determination 2 - Hot
The A/F sensor (sensor 1) internal resistance value [AF SENSOR IMPEDANCE] is 250 ? or more for at least 1.0 second.

Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
A/F sensor (sensor 1) heater failure
A/F sensor (sensor 1) element failure

Confirmation Procedure
Operating Condition
Start the engine, and let it idle for at least 1 minute. When engine coolant temperature [ECT SENSOR 1] is 5 °F (-15 °C)*5 (14 °F (-10 °C))*6 or less, let the engine idle for at least 6 minutes.

*5: 2013, 2014 models

*6: 2015 model on and after

With the HDS
None.

Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.