Knock Sensor
Due to the design of the knock sensor input circuitry, a short to battery, short to ground, or open circuit all result is a low knock signal voltage output. This output voltage is compared to a noise signal threshold (function of engine rpm and load) to determine knock sensor circuit high, circuit low or performance faults.
Some PCM/ECM modules use a driver circuit that will periodically and actively test the knock sensor lines for short circuit faults. In these modules, supplemental codes can be set for the short circuit condition. Some PCM/ECM modules use a standalone Knock IC. In these modules, the knock signal processing chip SPI bus is checked for proper communication between the main processor and the chip used as the interface the knock sensor.
The P130D code is associated with the "Low Speed Pre-Ignition" or "Mega Knock" strategy. Mega Knock is a phenomena present on GTDI engines during boosted operation. It is much more audible than normal engine knock and generates higher cylinder pressures that can result in the potential for engine damage. It tends to occur at lower engine speeds (< 3000 rpm) but may also occur at higher speeds. It tends to be an infrequent and random event. When it occurs, it may occur as a single event or as a burst event with multiple occurrences in rapid succession on the same cylinder. The code is set if the Mega Knock detection rate is too high.
| DTCs | P0325 - Knock Sensor 1 Circuit P0330 - Knock Sensor 2 Circuit P0327 - Knock Sensor 1 Circuit Low P0328 - Knock Sensor 1 Circuit High P0332 - Knock Sensor 2 Circuit Low P0333 - Knock Sensor 2 Circuit High P06B6 - Lost Comm with Knock IC Chip P130D - Engine Knock / Combustion Performance - Forced Limited Power |
| Monitor Execution | Continuous within entry conditions |
| Monitor Sequence | None |
| Sensors OK | Not in failsafe cooling mode |
| Monitoring Duration | 2.5 seconds |
| Entry Condition | Minimum | Maximum |
| Time since engine start (function of ECT) | 60 to 20 sec | |
| Engine Coolant Temperature | 140 °F | |
| Engine Load (circuit codes) | 35% | |
| Engine Load (Mega Knock codes) | 90% | |
| Engine Speed (circuit codes) | 1500 rpm | 6000 rpm |
| Engine Speed (Mega Knock codes) | 1000 rpm | 4000 rpm |
| P0325 & P0330
Knock signal too low (function of engine speed): < 30 to 150 A/D counts (out of 255) P0327, P0332 (used only for PCM/ECM with corresponding diagnostic circuit) Voltage level from active knock sensor circuit probe below limit P0328, P0333 (used only for PCM/ECM with corresponding diagnostic circuit) Voltage level from active knock sensor circuit probe above limit) P06B6 (used only for PCM/ECM with standalone Knock IC) Cylinder events with missing communication from Knock IC > 200 P130D Mega Knock detection rate too high: > 10 Mega Knock events within span of several thousand combustion events. |