Frequently Asked Questions
What KMS products do I need?
There is no quick answer to this question. Every application is different and much depends on the modifications you intend to make to the engine and what application it will be used for. It’s best to first check out our website to see what options and products are available. You can contact one of our dealers or email us for more information and prices.
Where can I buy KMS products?
KMS products can be bought through our extensive dealer network or directly from us. Our dealers have been carefully selected to provide the best advice, support and quality of work to our customers. Please contact us for details of your nearest KMS dealer.
How much does a KMS system cost?
As mentioned before, the composition of a KMS system is dependend on the application and customers wishes. You can check our website for more information on KMS products. Retail prices can be found in the pricelists. This way you can get a good idea of the approximate cost of buying a KMS system. For a complete price please contact one of our dealers or send us an email.
Which serial number, software or firmware version do I have?
To check your PC software version, simply open the KMS software. The software version number is shown in the left bottom corner of the startup screen.
The firmware version of your ECU can also be seen in the software. Just open your PC software and go to ‘Options (F4)’ when you are in the main screen. In the top of the opened screen the version info and serial number will be displayed.
I have no communication with the KMS ECU.
First make sure that the communication cable is not damaged and has been properly connected. Check whether ECU is powered (i.o. it has ground and receives a voltage supply above 11V). Then open the software and make sure that the communication port (comport) has been set properly, see also our manuals for setting the comport. If there is still no communication, check whether your PC software is functioning in the correct compatibility mode, see software for more information. Also make sure that the latest communication driver is installed on your computer, see software for more information.
If you still have no communication, it could very well be that your ECU has been locked with a password. Please verify this before contacting us or one of our dealers.
There is a password set in the ECU.
When there is password set in the ECU, it’s likely that your tuner has set this password. Please first contact the previous tuner for unlocking the password. If you have lost of forgotten your password, send us an email stating where and when you purchased the item and what serial number it has.
Can I install and tune A KMS system myself?
KMS products and software are developed to provide customers a user friendly and easy to use system. However despite our extensive manuals and wiring instructions, installing and mapping an engine management system still requires a good understanding of engine dynamics and electrics. Incorrect use or installation of a management system will inevitably lead to engine failure. KMS cannot be held responsible in any way for any damage caused by improper installation and use of KMS products. If you are unsure about doing this all yourself, it’s best to contact us or one of our dealers for help and more information.
My engine won’t start?
If your engine won’t start, you have to check a few things. Make sure that the ECU is powered (also under cranking), i.o. it has ground and receives a voltage supply above 11V, and you have communication with the unit. If this is correct the following problems could stop your engine from starting.
I have no igntion/spark.
You can check if there is any ignition by cranking the engine with the spark plugs removed or by using the ‘Output test’ in the KMS software. Make sure that all cables are not damaged and that there is no shortcut. Check whether ECU and coil are powered, meaning that the voltage supply must be above 11V and ground properly connected, see wiring for more information. While checking the power and ground, also make sure that the ignition outputs are wired properly and in the correct sequence according to the firing order.
Next, the spark plugs must have the correct colour, heat range and spark plug gap. Changing them is never a bad thing. The spark plug leads must have resistance and may not be cracked or rigid. This will mean that the leads are old and must be replaced. Also check whether the ECU is receiving any RPM signal.
I have no injection.
You can check if there is any injection by cranking the engine or by using the ‘Output test’ in the KMS software. Make sure that all cables are not damaged and that there is no shortcut. Check whether ECU and injectors are powered, meaning that the voltage supply must be above 11V and ground properly connected, see wiring for more information. While checking the power and ground, also make sure that the injection outputs are wired properly.
It’s only possible to use high impedance injectors with the KMS ECU. To check this, measure the resistance between the two injector pins, this must be higher then 12 ohm. Furthermore you can also check the fuel pressure to make sure that the injectors can inject high pressure fuel into the engine.
I have no RPM signal.
To check the RPM signal, open the KMS software and look in the left bottom corner. During cranking of the engine, the rpm should be between 75 and 300 rpm. If this is not the case, you can check the trigger signal under ‘Cranksensor test’. The tooth count crank should be the same as the set trigger wheel. If not check whether the correct trigger wheel has been set in the software. Also make sure that the correct cranksensor type (hall or inductive) has been selected and that the sensor is wired correctly, see our manuals for more information.
To determine which cranksensor you have, measure the resistance between the pins in the sensor connector. When it’s an inductive sensor, the resistance should be between 0.5kΩ and 2 kΩ. When the sensor uses a 3 pole connecter, there should also be the resistance of 0.5kΩ – 2 kΩ between two pins. The remaining pin is the shield of the sensor cable. If resistance cannot be measured, the sensor will be likely a Hall effect sensor.
If your using a hall effect sensor, make sure that is has correct power (5, 8 or 12V) and ground. When using a inductive crank sensor make sure that the signal and ground are twisted and preferbly shielded, both ground and shield must be connected. It’s also very important for an inductive sensor to be straight in front of the trigger wheel and within a distance of 0,5-0,7mm from the triggerwheel.
When there is still no RPM signal, try to connect an oscilloscope to the signal and ground and make sure that the reference point (missing tooth on triggerwheel) is going up through the zero point. If this is not the case or you do not have the use of an oscilloscope, try to switch the ground and signal wires on the sensor.
Has the ignition timing and firing order been set properly?
If the engine still won’t start make sure that the ignition outputs have been wired correctly according to the engine’s firing order, see wiring for more information.
The ignition timing/reference point must be set correctly in order for the ECU to spark on the correct timing. The reference point is the angle between the crank sensor and the first tooth after the missing tooth at the triggerwheel, at the moment that the first cylinder is in TDC. The reference point can be set between 0 and 180 degrees but it’s recommended to make it between 70 and 120 degrees, see our manuals for more information.
To check the ignition timing/reference point, remove the sparkplugs from the engine and place them, with the coils/leads connected, on the engine block/head. Mark the TDC on the crankshaft pulley or flywheel. Check with a timing light the degrees when igniting on cylinder1 in TDC while cranking the engine. If the ignition advance set in the software deviates from the measurement with the timing light, then you have to correct the reference point in the software untill the values are the same. Note: when using a wasted spark system, the timing light often displays a value two times the normal ignition advance.
