DTC Advanced Diagnostics: P0326 (1.5L Engine)
DTC P0326: Knock Sensor Malfunction
General Description
A nonresonant type of knock sensor is used, and it is mounted on the cylinder block to detect engine knocking. Vibration from engine combustion causes the torus-shaped weight to compress the ceramic element in the nonresonant knock sensor, and converts it into electrical signals. The powertrain control module (PCM) controls the ignition timing according to the electrical signal level. If the signal level from the knock sensor drops for a set time because of a poor connection at the knock sensor, or a bad sensor, the PCM detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Once per driving cycle |
| Sequence | None |
| Duration | 5.0 seconds or more |
| DTC Type | Two drive cycles, MIL on |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| Elapsed time after starting the engine | 5.0 seconds | - |
| Engine speed [Engine Speed] | 2, 000 rpm | - |
[ ]: HDS Parameter
Malfunction Threshold
Either one of the conditions is met for at least 5.0 seconds.
- The knock sensor output signal strength is 65 or less at the engine speed [Engine Speed] of 2, 000 rpm*.
- The knock sensor output signal strength is 135* 1 (170)* 2 times or less at the engine speed [Engine Speed] of 3, 000 rpm*, * 1 (3, 250 rpm)*, * 2.
*: Depending on engine speed and load.
*1: CVT
*2: M/T
Possible Cause
The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- Knock sensor misinstalled
- Knock sensor failure
Confirmation Procedure
Operating Condition
- Start the engine. Hold the engine speed [Engine Speed] at 3, 000 rpm without load (CVT in P or N, M/T in neutral) until the radiator fan comes on.
- Drive the vehicle at an engine speed [Engine Speed] 2, 000 rpm or more for at least 5 seconds.
- Drive the vehicle in this manner only if the traffic regulations and ambient conditions allow.
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, the freeze data, and the on-board snapshot 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, the freeze data, and the on-board snapshot can be cleared with the scan tool clear command.