ENGINE RUNNING DIAGNOSTICS AND TESTING- ICM1
The Engine Running Diagnostics and Testing screen (Pg. 420) is used to view the current timing source configuration and identify if there are any issues present.
- “Inputs” – Displays the status of the configured input signals
- “Teeth” – Displays status of the flywheel teeth
- “Input Noise” – Displays the percentage of erroneous signals detected over the previous 10 seconds
- “Other Errors / Warnings” – Displays various issues detected
- “Min Flywheel rotations not yet reached” – The engine has not turned enough times yet to start sparking. User-settable in the engineering screen.
- “Engine overspeed shutdown” – The overspeed shutdown fault occurred and has not yet been cleared
- “Engine underspeed shutdown” – The underspeed shutdown fault occurred and has not yet been cleared
- “Bad configuration- check setup” – The configuration is invalid (e.g. a cylinder is used in the firing order twice)
- “Critical timing error shutdown” – The TDC signal was lost for 2 seconds while the flywheel was still running.
- “Hall signal weak” – The hall pulse has been intermittent but occurring at the correct location after missing one or more cam turns.
- “Previous Shutdown Cause” – Displays the reason for the previous ignition shutdown
- "None/Reset (Engine has not gone from running to stopped since power on)" – The engine has not shutdown since the ignition has been powered on
- "Generic stall (ignition was firing when engine died)" – Engine stalled while the ignition was firing
- "User disabled" – The ignition was killed by selecting the “Shutdown Engine” button from the “System Menu” screen
- "External disable (shutdown line was pulled low)" – Ignition is disabled from the annunciator
- "Critical alarm shutdown (e.g. overspeed/underspeed)" – An overspeed or underspeed event occurred
- "Critical timing fault- timing signals were too poor to continue firing" – The magnetic pickup or Hall sensor signal lost integrity
- "Generic stall low RPM (ignition was firing when engine died)" - Engine stalled while the ignition was firing
ENGINE RUNNING DIAGNOSTICS AND TESTING- ICM2
The ICM2 Engine Running Diagnostics and Testing screen (Pg. 422) is used to view the current timing source configuration and identify if there are any issues present.
- “Encoder” shows encoder status
- “Counts per rev.” is a factory setting for the encoder
- “Last rollover” shows what the last rollover for the encoder was, which should always match “Counts per rev”. If this number is slightly off, there could be an encoder or noise issue. If this number is above 60,000, then the encoder is running backwards, in which case the calibration step needs to be completed.
- “Encoder Turning” / “Encoder Index Moving”: These show the movement of the encoder, which should be “No” when the engine is off and “Yes” when the engine is moving. If these stay “No” with the engine cranking, then there could be an issue with the encoder, drive shaft, coupling (“biscuit”), or internal gearing slipping.
- “Sparks” shows the total number of sparks since power on, and total number of misfires.
- “Other errors and warnings” will show other faults, if present. This list is the same as in the ICM1 in the previous section.
- “Previous shutdown cause” shows the last reason the ignition stopped firing. The list is the same as in the ICM1 in the previous section.
ENGINE OFF DIAGNOSTICS AND TESTING
The Engine Off Diagnostics and Testing screen (Pg. 421) is used to test ignition component operation and wiring when the engine is off. In this mode you can enter Compression Testing Mode, and can run wiring and firing order tests.
The left box can be used to select an individual cylinder to test sparking to verify wiring. To test a cylinder, select ‘Test’ next to that cylinder. When testing is active, the ignition coil under test will fire continuously. To check the component health or activity, use a spark checker tool or observe the spark information on the right side of the screen. To end the test, select the “End Test” button.
The text labels for the cylinders will illuminate blue while under test. On the Ignition Home screen (Pg. 400), the status will display “Firing Order Test Mode”.
The ‘Compression Testing Mode’ button can be selected when there are no individual cylinder tests taking place. This locks out the ignition system so that the user can crank the engine for a compression test without the coils firing. Click ‘End Test’ to exit this mode.
Engine Off Diagnostics and Testing Screen
TIMING CALIBRATION AND TACHOMETER OUTPUTThe Timing Calibration and Tachometer Output screen (Pg. 423) is used to adjust the ignition calibration value and the tachometer output.
“TDC Calibration” is used to adjust timing to match the actual timing observed through a timing light, if different. Timing disparity between the displayed timing of the ICM and a timing light are due to TDC index trigger bolt being installed not precisely at TDC. Note that the ‘Current Timing Displayed’ value will not change as the offset is adjusted, instead the value read on the timing light will change. Once the timing light matches the current timing, the signal is calibrated.
When doing an initial calibration of the engine, it can be useful to set RPM advance to be constant so that the timing does not move around while calibrating
If the trigger was installed BTDC, the offset will be negative. If the trigger was installed ATDC, the offset will be positive.
The “Tachometer Output” setting is used to set the number of pulses per revolution for the Tachometer Output pin on the ICM. This can be used to display RPMs on other devices, such as a Murphy TTD panel. Press the button to change the number of pulses on the tach output for every flywheel revolution.
If connecting the tachometer output to the MPU input of a TTD panel, the TTD must be configured to match the pulses per revolution set on this screen. The TTD only looks for RPM on the MPU input if the pulses are greater than 17. A value of 100, or more, is recommended.