Frequently Asked Questions

I ordered a hall effect sensor from you and I am testing it on the bench - I can't get a signal!

Our Hall Effect sensors for both wheel speed and Ref/Sync require a 1 k Ohm Pull-up to 5 volts. When you connect the sensor to the ECU, this is done internally. On the bench you will need to tie this resistor in between the 8 V feed and the signal and then measure the signal. You should see a normal square wave signal which is low when the tooth is in front of the sensor.

How do I know if my sensor is a rising or a falling edge?

To know for sure if you sensor produces a rising or a falling edge you need either a lab scope or a DVOM. If you have a lab scope, bring up the waveform of the sensor. If it is a hall effect sensor, you may use which ever edge suits the situation best. For example if your sync sensor is a hall you may find that one edge produces a more favorable sync signal position in relation to the crankshaft. If your sensor is a mag type sensor, look at the waveform as it crosses the 0v line. If the waveform is changing from negative to a positive as it crosses 0v it is rising. If the waveform is changing from positive voltage to negative voltage - it is a falling edge. To use the DVOM on a Mag Sensor, disconnect the sensor from the harness. Plug the red lead of the meter into the signal terminal of the sensor and the black lead to the 0v terminal. Place a steel object (like a screwdriver) against the sensor. Set the DVOM to read DC volts. Quickly remove the metal from the sensor and watch the direction the voltage goes either positive or negative. If the voltage goes negative, the sensor is a falling edge sensor if the signal is connected where the red lead of your meter is connected. If the voltage goes positive, the sensor is rising edge if the signal is connected where the red lead is connected.

The plugs and injectors don't fire in the right order even if we change the firing order in the software - what's wrong?

The ECU only triggers its outputs in ascending order. The software does not change the order in which the outputs fire. You must match your engine's firing order to the output firing order on the ECU in the wiring harness. For example, if your engine's firing order is 1,3,4,2 then 1 should go to ECU 1st to fire, 3 should go to ECU 2nd to fire, 4 should go to ECU 3rd to fire and 2 should go to ECU 4th to fire. The same holds true with an Ignition Expander or CDI-8 unit.

How do I test my ignition outputs if I have an Ignition Expander?

You can't readily do an ignition test with an Ignition Expander. But you can change the setup a small amount and still make the coils fire individually by jumping terminals at the Expander connector. First you must change General Setup so that the Ignition Type is set to the proper edge for your Ignitors. Then, change the number of coils to 1. Now unplug the ignition expander, and jump from the EST input terminal, to the first to fire output terminal. Now go under Diagnostics and you may perform and ignition test. To check each coil, simply move the jumper to the appropriate pin in the Expander connector.

Our engine wont start - what should we do?

In order to run, the engine needs 3 things Air, Fuel and Spark at the right time. First you should check to see that there is spark, injector pulse and fuel pressure. If you are missing both spark and pulse, look at the error screen while cranking. See if Sync Status changes to OK once you are cranking. If it does not, make sure the basic setup is correct (Ref/Sync Mode, Number or Crank Teeth etc.) If sync status is okay and you have no spark or pulse, do a diagnostic test and make sure you get both spark and pulse. Once sync status is okay the ECU will provide both spark and pulse - assuming this ignition system and injectors have power.

If you have both spark and pulse and it wont start, use a timing light on the number 1 wire. Crank the engine with all spark plugs out and spark plug wires grounded. Go into the CRiP Set Screen and make sure the timing you see with the light, is the same as what is defined in the screen. If not, adjust the CRiP until they match. Remember your CRiP can still be out by 1 revolution even if the marks line up properly. Try adding 360 degrees to your CRiP and see if that helps.

How can we use the Traction Control Features of the MoTeC?

There are several ways to utilize Traction Control. Ultimately we need at least 2 inputs for wheel speed connected to the ECU. We can either run these 2 inputs directly to the 2 digital inputs the ECU has or we can use a Traction Control Multiplexer (M TCMUX). The TC MUX allows up to 4 wheel speed channels to be sent to the ECU using only 1 ECU input channel. This allows better sensing signals and allows the additional switched input to the ECU to be used for a separate function as desired.

The TC MUX requires 8 V and 0 V supply from the ECU and its output is connected to the ECU's Digital Input 1 or 2. Then the Hall Effect Sensors can be connected to the TC MUX directly and they can measure wheel speed or shaft speed. The Sensors do not require a magnet to trigger so they can be easily adapted to read the bolts holding a sprocket or a brake rotor. For the best results especially at low speeds, a minimum of 12 teeth per revolution is desired.

What is the best way to mount a 3 Axis Accelerometer?

The best method is to locate the center of gravity of the vehicle and mount the sensor near or on top of it if possible. The best method of attachment is usually 2 sided tape or Velcro. Do not rigid mount the sensor using fasteners. Also you will want to orient the sensor in such a way that the wire lead comes out from the rear - that is it goes toward the rear of the car. Additionally, you will want the mounting flange to be down while the decal which describes the axes is facing upward.