What does the KSC knock detection system do?
The Knock Sensor Controller (KSC) is an engine knock detection system which outputs a 5 volt signal and 12 volt signal when it detects engine knock.
The knock frequency is user programmable and the knock frequency of an engine can be found using the in-built “Knock ID” tool.
The knock volume threshold is also user programmable and the knock volume threshold can be found using the in-built “Baseline” tool.
The 5 volt output can be sent to the engine’s ECU so it can retard ignition timing.
The 12 volt signal can be connected to audio or visual indicators to alert the driver in real-time. We recommend the use of a visual indicator like LED strip especially in noisy vehicles.
The Knock Sensor Controller unit is designed to be mounted in the engine bay, away from heat and moisture.
The KSC unit is programmed via Bluetooth using the KSC2 Android app.
Knock Sensor Controller (KSC) – Features
Adjustable knock frequency
Using the in-built Knock ID tool the minimum and maximum monitored frequency can be selected. This helps compensate for installation, knock sensor location and engine characteristics which may move the actual knock frequency away from the theoretical knock frequency of the engine.
Adjustable knock volume threshold
When the volume threshold and count threshold are met or exceeded the unit will output a 12 volt signal (max 3 amps) and a 4.5 volt signal (max 2 mA). These can be used to integrate the knock signal with a device of your choice.
RPM dependent monitoring.
The MoviChip KSC2 uses a 0-15 volt rpm signal input. The knock volume threshold will change according to the RPM of the engine.
The Knock ID tool shows you the volume signal from the knock sensor for each frequency band.
By using a known conservative ignition timing map, we can compare the volume vs a map where we have induced light knock.
The frequency band where the volume has changed will indicate the knock frequency.
Audible Knock Monitoring
A way to audibly detect engine knock is essential in setting up the KSC. Fortunately it is extremely cheap to build a high quality, DIY knock detection system with a Windows laptop.
Because this solution for audible monitoring is so cheap and effective we have not burdened the KSC with audible monitoring. If you only need audible knock monitoring then we highly recommend this free option.
Knock Detection System – Benefits
The MoviChip KSC control unit is designed to be mounted permanently on the vehicle, in the engine bay. This is typical of most MoviChip products and we do this to simplify installation. You do not need to find space to mount an ECU box in the cabin of the car and you do not need to runs wires from the engine bay into the cabin or splice into the wires inside the cabin. The KSC is designed to be a largely fit-and-forget item.
We like big screens and we dislike having to scroll through menus using arrows and buttons. This is why we harness the power of modern Android smartphones. Big screen means you do not have to dig through menus to get to what you need
You only need to use the app if you want to adjust settings or to check data coming from the unit. In normal use you just get in the vehicle and drive.
Knock Sensor Controller – Specs
Knock Detection System Connections
Ignition Power (12v)
Knock Sensor +
Knock Sensor Ground
RPM Signal (0-15v)
5 volt output – Knock Warning Output to Engine ECU (2mA max)
12 volt output – Buzzer/LED Power etc (3 amp Max)
12 volt output – Negative
Knock Signal Gain
Knock Signal Volume Threshold
Knock Detection System – What Is Included?
Knock Sensor Controller 2.0 Unit
Industrial grade connector and crimps
Android App – Download from the MoviChip website
User Manual – Download from the MoviChip website
What else is required
Android device with Bluetooth.
User built wiring loom
Knock sensor – We recommend Bosch or Bosch-type knock sensors part number 0261231173 or equivalent.
Genuine Bosch sensor and connectors can be bought here.
Bosch-type knock sensors and connectors can be bought at online auction sites
Knock Sensor Controller – Quick Start Guide
We need to define what will count as a knock frequency, our knock frequency calculator will get you started. The Knock ID tool will confirm the knock frequency
With a conservative ignition timing map where we know no knock will occur, turn on the “Baseline” tool and carry out a high load run from 1000 rpm to redline. Before lifting throttle, press “Off”.
The Baseline tool will output the peak volumes.
Enter volumes slightly higher than these in the “Saved Volume” sections. You have now set your volume threshold.
The KSC will output the 12 volt and 5 volt signals when the volume threshold is exceeded. The volume threshold is interpolated between RPM points.
The Knock Sensor Controller should never be used as the exclusive device to monitor engine knock and for safe engine operation in general.
Engine safety and knock should be monitored by numerous sensors to ensure there is some redundancy if any sensor or device experiences a problem.
Engine Knock Detection System Terminology
Knock Sensor Gain
The volume we will monitor, as outputted from the knock sensor during normal engine activity
The frequency window we listen to for knock. We set the minimum and maximum frequency.
Knock Volume Threshold
The volume level, which if exceeded, will count as a knock event.