INTERNAL EMM FUNCTIONS
Start Assist Circuit (SAC)
When the ignition key is ON, the EMM Start Assist Circuit (SAC) boost s battery volt age (12 V) to 30 V on the system (55 V) circuit.
If the SAC circuit current exceeds 2 Amps, or if the SAC voltage is less than 20 V, the EMM:
Stores service code 77
EMM LED 1: ON (Running)
ROM Verification
The EMM performs a self-test of programming every time it is turned ON. Service code 15 indicates a programming (software) issue. Re pro gram the EMM with the correct software program to correct the problem.
Idle Controller
The idle controller reacts to engine operating conditions. Fuel and ignition timings are altered to maintain a specific RPM when engine is cold or warm. The controller is inactive when TPS is advanced from idle position.
RPM Limiter
This feature of EMM programming prevents engine damage due to excessive RPM. At 625 0 RPM, fuel and ignition to the cylinders is shut off. Normal operation resumes when engine RPM returns to the specified range.
Neutral RPM Limiter
This feature prevents engine damage due to excessive RPM if accelerated in NEUTRAL. Neutral engine speed is limited to 1100 RPM.
Engine Monitor and Warning Systems
Refer to ENGINE MONITOR SYSTEM on p. 62.
Refer to S.A.F.E. WARNING SYSTEMN on p. 63. Refer to SHUTDOWN MODE on p. 63.
Fault Code Creation and Storage
Refer to the EMM Service Code Chart at the back of this manual for a complete list of all engine fault codes.
