These inputs are required by the ECU to determine exact crank and cams angles so that spark and injection timing can be calculated. VVTI cams can be positioned by the ECU. Their cam signals will be compared to the crank signal to determine the right position for loop control. Version 3.5 can only do open loop cam control. The firmware may blank out or force the signals in a state depending on the specific engine.

Crank (TDC)
The crank angle sensor is used by the ECU to determine exact crank degrees as it rotates. This sensor could be situated on the crank or in a distributor or encoder called a CAS. If it is situated on the cam gear like a distributor, then it will have enough pulses for 2 revolutions to represent the crank signal. For example, Toyota uses what we called a 24+TDC pattern. If the sensor is on the crank there will be 12 teeth. If it is on the cam there will be 24 teeth. If a pulse is generated on a 36-1 gear on a crank for example, then the missing tooth is used as a TDC pulse. A TDC pulse represent a signal that comes once every revolution. It is not necessary at TDC of the engine. In a distributor it may have a TDC pulse or Home pulse. If a pulse come once in two revolutions it is called a a home pulse.

With Firmware Ver 3.5E onwards, the test function is used during crank and cam sensor tests. When this bit is set there will be no fuel injected. With the new Cam Home teeth sink this helps to set up cams with different teeth for different engines. If the sensors are read incorrectly, or the ECU has the wrong firmware, the software will show errors in the bottom status bar. These Errors have numbers indicating a fault code and description. This is a very useful feature for first time startup after the installation is done. See Setting Crank Sensor Timing below. See the next section.

On older firmware, the engine will start after the second revolution if there are no errors. Note. After setup put the test faction off. It may bother at high RPM’s due to the calculations to determine correct patterns.

Cam (Home)

The cam angle sensor will always be situated on a cam shaft. It could be a lone sensor in the valve cover or in a distributor. This signal only came with later models when full sequential injection was introduced. Some distributors like Nissan and Toyota had both sensors in the distributor. The cam signal will give a unique pattern over two revolutions, allowing the ECU to detect which revolution is the firing stroke. This signal could be one pulse or a number of pulses. The ECU can compare it with the crank signal pattern and determine firing stroke.

This feature is incorporated in the new version 3.5E firmware to determine a home pulse position from different cam signals. Each manufacture uses a different cam pattern. One of the cam sensors must be connected to the ECU and selected. During setup, start with teeth 1 and crank the engine. It should show missing home pulses on the error codes. Increase the value and press C for clear after each adjustment. If the error stops appearing, at for example 4, then continue increasing till you see the error again. If the value is 10, for example, then set the teeth setting in the average of 7 teeth. Now the ECU knows the difference in stroke 1 and stroke 3 of the engine. One will have a pulse within 7 teeth after the slot and 3 will have no pulses. Note that Full Sequential Injection or Full Sequential Spark must be on to produce errors. Also not that Full Sequential Injection is still possible without a Cam (Home) pulse but not Spark. You need to have the Cam sensor setup correctly for spark.

Cam Control Selection

This feature will reduce the number of firmware files required for different engines. Previous version was split in a normal engine or specific VVTI engines. VVTI consists of 2 cam control settings for inlet or exhaust cams. Control is still open loop so for V engines the 2 Cam solenoids are connected on the same driver. It requires only 1 x 3Amp diode to be installed. No input Cam sensors are required in open loop control. Also note that cam control will be 25% duty cycle when Off and 75% duty cycle when On. If your engine requires different control parameters, then you need to load the engine specific firmware.

First you need to select 1 or 2 cam outputs. Note that the software will refresh the setup data as these drivers are shared with GP output drivers. If you don’t use cam outputs, then un select them to free up the GP drivers.

Then the cam control block will become visible also indicating which drivers are used for which coil. If no drivers are visible, then the cam selections are not selected.

Take note that Cam1 is used Cyl1 in V engines or Intake Cam. Cam2 is used for the opposite cam than Cam1 or the Exhaust Cam.

Should the engine have an intake Flap then use the V-Tech feature on GP2 for it as it has a TPS limit as well.

Dedicated firmware like the Lexus VVTI will use the Intake block in the VVTI settings block.

Setting Crank Sensor Timing

This block is used to indicate to the ECU where the exact TDC point is on the crank. It works differently for the different style of crank angle sensors. These settings will allow the ECU to synchronize software timing with the actual spark timing on the engine.

On gear type trigger wheels, the Gear Teeth will indicate to the ECU the amount of teeth between the slot and TDC. The Timing Sensor will do finer adjustments to precisely set the timing in-between the teeth.

The example below explains, if you put the engine of a 36-1 trigger wheel on TDC, count the number of teeth from the slot anti clockwise to the pickup sensor plus the one just past the sensor. Put this value in . Then you may adjust the Timing Sensor from 0 to 9 degrees to precisely align the timing light to the tuning software. The example below should work out as Gear teeth 7 Timing Sensor 6 as the last edge of the teeth is in the center of the sensor.

With the engine running match the timing as close as possible by using the Gear teeth setting. For example; the ECU software indicates 10° advance on the real-time bar, but you see 12° advance on the engine. The Timing sensor °BTDC will now be adjusted to accommodate the difference which is 2. With the Timing sensor adjusted the Timing light and the ECU should now be matched.

Important!
When using an Advance / Retard timing light on a wasted spark system the timing light will read double the timing of the engine. So if the timing light reads 20° advance, the actual ignition timing is 10° advance. If you are not sure rather put the timing light on zero degrees and use the pulley marks. Remember that the COP systems are still fired in wasted spark sequence.

On single event triggers you will find that gear teeth are not adjustable only the degrees between the triggers. On a 4Cyl Nissan for example the timing sensor may be adjusted to 180 degrees.