CAM detection information
The cam and crank pattern detection for most trigger systems is done separately.
The cam trigger looks for a unique pattern, to make it sync faster this usually doesn't need to be all teeth for a complete cam revolution, for example the VW 1.8T (CAM) it looks for 2 teeth consecutively 25% shorter than the previous teeth.
This only occurs once per cam rev. On the crank, at the first tooth after a mission gap, it checks if the cam detector has seen the unique cam pattern during the last 360 degrees of crank revolution. If it has seen the cam pattern, it considers the first tooth after the missing gap as tooth 0 and starts handling fuel, dwell and spark events.
From this point, the trigger system doesn't care about the cam pattern, as long as it's in sync (the VVT system does of course, but that's a different system). IF it loses sync (crank trigger errors), it needs to see a cam pattern match in the last 360 crank degrees before it syncs again.
(This only applies to missing tooth trigger, triggers with even crank teeth require a constant cam match for safety). For most trigger combinations there's only one possible sync point every 720 degrees of crank rotation (the first tooth after the missing gap, after it has gotten a cam pattern match).
So depending on the angle where the engine has stopped, it may need to rotate 720 degrees before it finds the sync point at tooth 0 and can start, it can also be a lot less than 720 degrees if the engine is in a favorable position.
Some trigger systems like the GM 24x system can sync at many different points to start very quickly (it can find other sync points than just 0), but this puts a higher demand on the angle relationships and sensor types.
The general approach, like on a VAG cam with 60-2 on the crank, is more forgiving about where the signals on the crank and cam are in relationship to each other, which we prefer as cam/crank sensors are often mixed and moved.
See trigger problems for an explanation of polarity, arming voltage and so on.
Trigger
trig sensor type
Specifies input type of the sensor.
•Digital (hall, opto, etc) - Used with digital sensors.
•VR-sensor, Zero-crossing - Used with VR sensors, you will normally use this setting with VR sensors.
•VR-sensor, Bipolar - Used in very rare cases where the zero crossing is is very slow/long causing an undefined zero-crossing point.
trigger polarity
Specifies whether to trig on rising or falling edge of signal.
Arming voltages <-- only available for VR-sensors.
The voltage of the signal to be used as the trigger point.
•Manual table - Manually enter the trigger arm voltages in the table. Use the built-on oscilloscope to determine the levels, a good presentation is to use 50% of the highest voltage detected at the given RPM.
•Automatic tracking - Automatic trigger arm tracking, uses 33% of the peak voltage from the previous rotations.
threshold voltages <-- only available for digital sensors.
The voltage of the signal to be used as the trigger point, can be used to tune the voltages if the sensor output voltage is lower than usual.
•default (3.5/2.0V) - Manually enter the trigger arm voltages in the table.
•Custom settings: Rising edge threshold - The voltage over which the signal is considered "high". Should be at least 0.5V above the falling edge threshold, and preferably at least 0.5V below the actual high voltage.
•Custom settings: falling edge threshold - The voltage below which the signal is considered "low". Should be at least 0.5V lower than the rising edge threshold voltage.
Threshold voltage example
Your highest voltage is 3V, and lowest voltage is 1V, then Rising edge threshold should be ~2.5V and the Falling edge threshold should be ~1.5V.
trigger pullup resistor <-- only available for digital sensors.
Whether to use the internal pull-up resistor or not. Only available on digital inputs.
HOME input
HOME sensor type
Specifies input type.
•Digital (hall, opto, etc)
•VR-sensor <-- Not available on all ECUs.
•MAP-sensor - Uses the MAP sensor as HOME input (ADVANCED).
•On digital input - The physical HOME input signal is discarded and using a selected Digital input (Trigger, CAM/HOME, Trigger, HOME+CAM dual sensor, cam sensor) as HOME instead.
•Not used
Map dip threshold
When the home sensor type is set as map-sensor, this setting is used to used to determine the least amount of MAP-signal pressure drop that counts as HOME/cam signal.
Note: to setup, it is required to use the internal ECU Logging at least 500hz to determine the proper MAP DIP value.
HOME polarity
Specifies whether to trig on rising or falling edge of signal.
Arming voltages <-- only available for VR-sensors.
The voltage of the signal to be used as the trigger point.
•Manual table - Manually enter the trigger arm voltages in the table. Use the built-on oscilloscope to determine the levels, a good presentation is to use 50% of the highest voltage detected at the given RPM.
•Automatic tracking - Automatic trigger arm tracking.
threshold voltages <-- only available for digital sensors.
The voltage of the signal to be used as the trigger point, can be used to tune the voltages if the sensor output voltage is lower than usual.
•default (3.5/2.0V) - Manually enter the trigger arm voltages in the table.
•Custom settings: Rising edge threshold - The voltage over which the signal is considered "high". Should be at least 0.5V above the falling edge threshold, and preferably at least 0.5V below the actual high voltage.
•Custom settings: falling edge threshold - The voltage below which the signal is considered "low". Should be at least 0.5V lower than the rising edge threshold voltage.
Threshold voltage example
Your highest voltage is 3V, and lowest voltage is 1V, then Rising edge threshold should be ~2.5V and the Falling edge threshold should be ~1.5V.
trigger pullup resistor <-- only available for digital sensors.
Whether to use the internal pull-up resistor or not. Only available on digital inputs.
trigger decoder
Trigger system
See, trigger systems for a list of available trigger systems.
Home signal
See, trigger systems for a list of available home trigger systems.
Tooth offset 1/2
Only available when using the Crankshaft Deceleration HOME sync.
min difference
Only available when using the Crankshaft Deceleration HOME sync.
Cam signal position
Specifies whether CAM signal is received before or after TDC.
teeth count
Specifies number of teeth on crankshaft trigger wheel INCLUDING missing teeth's.
missing teeth
Specifies number of missing teeth's on trigger wheel.
Sync window size
Specifies length of the longest hole in the CAS trigger wheel. Only visible with Nissan CAS trigger.
CAM signal position example
If you are running a sequential trigger system and you detect that the system fires on the wrong engine cycle (360 degree wrong), flip this setting. (it is the same as adding 360 degree to the below first tooth angle).
advanced trigger options
Note: Only visible when a missing tooth trigger system i selected.
unsyncronized start
Allows the engine to start faster by starting the engine without the cam signal.
Note: Make sure the engine start in sequential mode all the time, BEFORE enabling this feature.
•disabled - Slower start and waits for the CAM sync before firing the coils.
•enabled, starts in wasted spark, stops if cam is missing -The engine is started in wasted spark and 360 fuel modes and is switched to fully sequential as soon as the cam signal is available. If no cam signal is sensed within 3 seconds the engine is stopped and an error code is set.
•enabled, starts in wasted spark, keeps running if cam is missing -The engine is started in wasted spark and 360 fuel modes and is switched to fully sequential as soon as the cam signal is available. If no cam signal is sensed within 3 seconds the engine will continue to run in 360 fueling and wasted spark.
Before enabling the above enabled, starts in wasted spark, keeps running if cam is missing, BE SURE to understand that it WILL MOST LIKELY damage your engine to put load on the engine if it is tuned for 720 fueling/ignition, it is just not bad, it could be catastrophic.
Knock control will not work properly without the CAM sensor, be aware and threat the above keep running if cam sensor missing as a limp home mode.
Requirements for the unsyncronized start option:
•Crank trigger is a missing tooth trigger.
•Any cam pattern.
•Even cylinder count.
•Fuel in 720 degrees.
•Ignition in Coil on plug mode.
See 39 - Trigger error: No cam signal / incorrect pattern which is related to the unsyncronized start feature.
Advanced trigger options
Enable/disable the advanced trigger options. Only activate if you have trigger problems during crank and know what you are doing.
Trigger time tolerance
Missing tooth tolerance
Is the required length of the current signal compared to the largest difference over the last two engine revolutions.
Note: 80% is a good starting point for an average looking trigger signal. The adaptive system is only used BELOW ENGINE Max cranking RPM in your engine settings.
Missing tooth threshold, cranking
A tooth this long in relation to the tooth before is considered a missing tooth while cranking. Can be used if the default calculations aren't suitable for difficult light high compression engines.
Missing tooth threshold, running
A tooth this long in relation to the tooth before is considered a missing tooth when the engine is considered running. Can be used if the default calculations aren't suitable for difficult light high compression engines.
ignore second missing gap
Ignores the length of the missing gap 360 degrees from the first missing gap. It can be useful for engines with odd cylinder numbers where the compression causes unequal gap lengths and the gap that's too deformed by compression can be ignored.
missing gap gating
Only allow the missing gap detector to work in a specified range after the last cam signal. Useful when normal teeth get so long that they can be mistaken for the missing tooth when cranking high compression or light engines.
It can be used together with the adaptive cranking tolerances or extra tolerance at low rpm settings. Use the Trigger oscilloscope to count the number of crank teeth after the cam signal.
min window count
Min number of crank teeth since the cam signal trigger edge to detect the missing gap. Subtract a few to have some margin for error.
max window count
Max number of crank teeth since the cam signal trigger edge to detect the missing gap. Subtract a few to have some margin for error.
trigger angle
First tooth angle
The actual sensor position from engine TDC.
Note: when you have engine RPM during cranking, this value needs to be synced with the spark advance seen on the engine with a timing light.
trigger angle options
Disable fuel
Check this checkbox to completely disable fueling (injectors and fuel pump).
Disable ignition
Check this checkbox to completely disable ignition outputs.
Note: When any of the above checkboxes is checked, it completely disables fuel and/or ignition outputs, even the Diagnostics --> Output test features.
Lock ignition angle
Check the checkbox to lock the ignition advance timing at a given value, regardless of engine load.
Note: all other ignition timing (even cranking angles and/or other corrections) will be discharged when this feature is enabled, use with caution.
Ignition lock angle
The given value to lock ignition to. Locks all ignition timing to the given value.
Supported trigger systems
MaxxECU supports VR and digital sensor (hall-effect, opto) on crank and/or cam.
Crank triggers
•Chrystler Hemi SRT-8 (32-2-2).
•Diahatsu Mira 3-cyl (3+1 on cam).
•Diahatsu Mira JB (4+1 on CAM).
•Dodge Viper V10 (gen 1 92-95).
•Dodge Viper V10 (gen 2 96-02).
•Ford Cosworth (4 on crank, 2 on cam).
•Generic 3+1 (extra tooth before).
•GM LS 24x, 1x cam.
•GM LS 24x, any cam pattern.
•Harley davidson EVO.
•Honda K20 (12+1) without CAM-sensor.
•Honda K20A2 (with CAM sensor).
•Honda K20z4 with CAM-sensor.
•Jeep Cherokee (MJ-XJ 19) 18-2-2-2.
•Jeep wrangler 2006 4.0L (36-2-2).
•Kawasaki JET SKI 1100 DI STX.
•KTM 450.
•Mazda RX8, 2 (Z engines) 36-2-2-2.
•Mercedes-Benz S600 M120-980 6.0L
•Mercury Marine 2.5L 2-stroke V6
•Mini Cooper SPI MK3 (36-1-1).
•Mitsubishi 6G75 (crank + CAM).
•Polaris RMK800 2014-2015 (6-1).
•Rover V8, 8+1 on crank.
•Rover K-series (lotus elise) 1.8
•Single pulse per 720 degrees (piggyback trigger).
•Subaru EJ20 (early) 6crank+7cam teeth.
•Subaru EJ20 (late) 36 teeth.
•Subaru EJ25 (early 6 on crank 1 on cam).
•Suzuki 13B sequential (requires modified trigger wheel).
•Suzuki GSX (with digital sensor).
•Suzuki Swift 2012 - 2017 K12B.
•Suzuki Swift M15A 2005 - 2010.
•Yamaha jet ski waverunner (2010).
HOME/CAM triggers
•On Cam (1 pulse per cam rev.)
•2JZ VVT 3-teeth.
•N-1 on cam - Missing tooth system. N teeth and 1 removed. N teeth and 1 removed (like 4-1 and 8-1). It is recommended to use at least 12-1 on the CAM.
•N-1 on cam (alt trigger point) - Missing tooth system. N teeth and 1 removed. For missing teeth triggers with at least 5 teeth where the missing gap overlaps crank missing tooth.
•N-1 on cam (alt trigger point 2) - For missing teeth triggers with few teeth where the missing gap overlaps crank missing tooth, OR very high compression engines where the regular N-1 trigger has problems syncing.
•N+1 extra tooth, on cam.
•Alfa Romeo Twin Spark 95 - 05.
•BMW 6+1extra on cam.
•BMW M62 (CAM).
•Diahatsu Mira JB (4+1 on CAM).
•Ford Cosworth (4 on crank, 2 on cam)
•Ford Mustang Coyote 5.0 V8 (CAM).
•Honda CBR1000RR (2+1).
•HONDA J35A3.
•Honda L15A.
•MAP sensor as sync on V-twin.
•Mazda MX5 NB cam trigger with missing tooth.
•Mazda 2 (Z engines).
•Mitsubishi Evo cam.
•Mitsubishi 6G75 (crank + CAM).
•Nissan CAS/GM LT1 cam with missing tooth crank.
•Porche 996 2000 variocam M96/70.
•Subaru 2-teeth cam/vvt trigger.
•Subaru EJ25 (early 6 on crank 1 on cam)
•Subaru MY06 - MY14 (WRX STI).
•Suzuki swift 2012-2017 K12B.
•Suzuki Swift M15A 2005 - 2010.
•Suzuki 15B.
•Volvo T5 VVT.
•Volvo T5 VVT early/exhaust cam.
•Volvo T6 VVT.
VVT triggers
•Even teeth - Wheel with evenly spaces between.
•Alfa Romeo Twin Spark 95 - 05.
•BMW 6 + 1extra - 6 teeth with an extra tooth between two of the others. BMW S50.
•BMW M62.
•Chrysler Hemi SRT.
•Honda K20A2 (4+1 on exhaust).
•LS3 CAM.
•8-1 missing tooth - Missing tooth system. 8 teeth and 1 removed.
•N-1 missing tooth - Missing tooth system. N teeth and 1 removed. N teeth and 1 removed (like 4-1 and 8-1).
•N-1 (alternative trigger position) - Missing tooth system. N teeth and 1 removed. Used where the missing gap on the cams would overlap the missing gap on the crankshaft.
•N+1 extra tooth.
•Volvo long-short - Two teeth per cam revolution, one long and one short.
•Mitsubishi MIVEC.
•Subaru 2-teeth cam/vvt trigger
•Subaru MY06 - MY14 (WRX STI).
•Suzuki Swift 2012 - 2017 K12B.
•Suzuki Swift M15A 2005 - 2010.
•Suzuki K15B.
•Toyota 3UR-FE.
•Volvo T5.
•Volvo T6 - Four different length teeth per cam revolution.
•Porsche 996 2000 variocam M96/70.
