BMW K100 LT Bedienungsanleitung

EFI/Electronic ignition K100 2v troubleshooting Disclaimer: This page is a guide but not a reference. I am not a professional but only a K100 enthus

If your injector is leaking internally or failing to close fully the bike might run OK depending on just how bad the problem is. The way to chec

Air traverses the air filter and goes to the air flow sensor. When you open the throttle, the depression is moving the internal vane of the air flow

This airflow meter is factory sealed. If you don’t experience problems avoid breaking the seal on the cover. Dirt on the circuit board will affect th

Now, let's get practical... EFI and Electronic ignition components:

The following graphic shows the different components and their connection to the EFI computer.

You can try to follow the full wiring diagram, but this is very confusing. To help you, I have detailed the wiring related to the EFI / Electronic i

Or if you prefer, this simplified schematic of the wiring:

Quick explanation of the principle: What's happening when you press the starter switch: The starter relay and Fuel Injection relay close, Hall

Water temperature sensor: The bike will not start if the water temperature is above the normal range of operation. A bad temperature sensor will sen

Electronic ignition module (female connector): Electronic ignition module test: Pin # Function Testing mode type Expected value 1 Direct ground co

First, here are a couple of schematics showing the location of the electrical components: Under tank connectors and ground Fuse box layout

Hall sensors: The Hall sensors are known to fail when hot. They are rated to operate at a temperature between -40 to +160 degrees Celsius. If t

Here is how to test the sensors. Any good sensor should light the LED until something metallic, like a feeler gauge, is introduced in to the sensors

volts are produced at the high voltage terminal, not enough to actually cause a spark. The actual spark is generated when the breaker contacts open.

Spark plugs and ignition wires: I have read on other forums people finding after market ignition wires and caps. This could be a big money saver, but

Electronic Fuel Injection . Here is a picture of the Electronic Fuel injection module female connector where the testing has to be done: Electro

LE-Jetronic (EFI) test: Pin # Function Testing mode type expected value 1 info on engine rpm When starter is running Volts ~ 10 to 20mv 2 Idle switch

Test of the air temperature sensor in the air flow meter: You will notice that the resistance decreases when the temperature rises. The value of

Testing the electrical power at the fuel injectors: Because of the injection time varying from 1.5ms to 9ms., it is best is to use an LED to test t

everything back and check the voltage at the injectors after each device is plugged back. Testing if the EFI computer is sending the "puls

Testing the fuel pressure To test the system fuel pressure, install a manometer in parallel with the fuel pressure hose. If the fuel pump an

Layout of electrical components (in the tray under the tank).

Testing the pump and fuel pressure regulator To test the fuel pressure output of the pump, install the manometer right at the pressure port of the ta

Now, let’s start the troubleshooting….. Is the starter turning? Here is a simplify schematic of the starter circuit

If the engine is cranking, continue with this chart.

You reached the orange box and the result of your investigation points to the EFI system. How does it works? You may not be an electronic engin

Fuel pressure regulator: Fuel pressure is sent from the pump to the Fuel injector rail. The fuel pressure regulator will keep a constant pressure i

Idle switch The idle switch (Also called butterfly switch or throttle switch) is located at the end of the fuel injector rail. It wills cut-off th

Fuel injectors: The 4 injectors all open and close at the same time when commanded to do so by the ECU. It's important to understand that the