System Self-Test
During engine start-up, pause with the key switch in the ON position. The horn self-tests by sounding a half-second beep. SystemCheck gauges self-test by turning the indicator lights on simultaneously, then off in sequence.
Service Mode
SystemCheck goes into a service mode if the key is left ON after self-test (engine NOT running). All light circuits and sensors are active, but the horn is not. Grounding the appropriate light circuit wire will turn the light on, but the horn will not sound. Refer to SystemCheck CIRCUIT TESTS on p. 131.
Engine Running
All warning circuits are active when the engine is running. The horn circuit is active when engine speed exceeds 500 RPM.
Engine monitor warnings activate the horn for 10 seconds and the appropriate gauge light for a minimum of 30 seconds. If the failure is momentary (for example, oil moving in the tank), the light will remain ON for the full 30 seconds before going out. If the fault continues, the light remains ON until the key is turned OFF or the failure is corrected. The warning will reoccur at the next start up if the problem is not corrected.
S.A.F.E. WARNING SYSTEM
The S.A.F.E. (Speed Adjusting Failsafe Electronics) warning system alerts the operator and protects against engine damage from the following abnormal conditions:
| Code 17 | Alternator 55 V below expected range |
| Code 18 | Alternator 55 V above expected range |
| Code 25 | EMM temperature above expected range |
| Code 34 | Oil injector open circuit |
| Code 40 | Engine overheat low speed |
| Code 43 | Cylinder head temperature above expected range |
| Code 117 | Critical LOW OIL Detected |
| Code 120 | LOW OIL switch open circuit detected |
Activation
When one of these conditions occurs, the EMM interrupts fuel injector and ignition operation, reducing engine speed to 1200 RPM. The warning horn sounds and an Engine Monitor message displays. When S.A.F.E. is active, the engine will run normally below 1200 RPM. Above 1200 RPM, the engine will shake excessively.
Recovery
The engine will operate in S.A.F.E. as long as the fault condition exists. To recover normal operation, two conditions must be met:
- Sensor or switch readings must be back within limits
- The EMM must be reset—stop and restart
