Knock Sensor Interface Description

The knock sensor interface consists of 4 input signal and 4 screen grounds. See Fig 1 .

There are four knock sensor diagnostic checks, a fault is detected if:

1. The engine speed is greater than 2200 RPM, the ECT is greater than 40.5°C (104.9°F) input voltage exceeds a minimum voltage threshold.
2. The engine speed is greater than 2200 RPM, the ECT is greater than 40.5°C (104.9°F) and the input voltage exceeds a maximum voltage threshold.
3. The engine speed is less than 5400 RPM, the ECT is greater than 40°C (104°F) and no knock sensor signal has been received.
4. The engine speed is less than 5400 RPM, the ECT is greater than 40°C (104°F) and the knock signal has deviated from the test signal.

Fig 1: Knock Sensor Monitoring & Enabling Conditions

Courtesy of LAND ROVER NORTH AMERICA, INC.