Polaris 2012 RANGER RZR 570, Руководство по обслуживанию, Страница: 151 / 403

4.11
ELECTRONIC FUEL INJECTION
4
9923523 - 2012
RANGER
RZR 570 Service Manual
© Copyright 2011 Polaris Sales Inc.
ELECTRONIC CONTROL UNIT (ECU)
Operation Overview
The ECU is the brain or central processing computer of the
entire EF I fu el/ignition ma nagement system. Dur ing
operation, sensors continu ously g ather data which is
relayed through the wiring harness to input circuits within
the ECU. Sign als to the ECU include: ig nition (on/off),
crankshaft position and sp eed (RPM), th rottle po sition,
engine coolant temperature, intake air temperature, intake
manifold absolute pressure and battery voltage. The ECU
compares the input signals to the programmed maps in its
memory and determines the a ppropriate fuel a nd spark
requirements for the immediate operating conditions. The
ECU then sends output signals to set the injector duration
and ignition timing.
During operation, the ECU contin ually per forms a
diagnostic check of itself, each of the sensors, and system
performance. If a fault is detected, the ECU turns on the
“Check Engine” light in the speedometer and stores the
fault code in its fa ult memo ry. De pending on the
significance or severity of the fault, normal operation may
continue, or "Fail- Safe" operation (slowed speed, richer
running) may be initiated. A technician can determine the
cause of the “ Check Engine” ligh t by re ferencing the
“Instrument Cluster Trouble Co de Display” a nd
“Diagnostic T rouble Cod e T able” or by using Digit al
Wrench™. The ECU requires a minimum of 7.0 volt s to
operate. T he memory in the ECU is operational the
moment the battery cables are connected.
To p revent en gine ove r-speed an d p ossible fa ilure, an
RPM limiting feature is programmed into the ECU. If the
maximum RPM limit is exceeded, the ECU suppresses the
injection signals, cutting off the fuel flow and retards the
ignition timin g. This process r epeats it self in ra pid
succession, limiting operation to the preset maximum.
RANGER
RZR 570 EFI RPM Limit:
Max RPM Limit - Injector and ignition suppression.
• RZR 570: 7750 RPM (All Gears)
ECU Service
Never attempt to disassemble t he EC U. It is sealed t o
prevent damage to internal components. Warranty is void
if the case is opened or tampered with in any way.
All operating and control functions within the ECU are pre-
set. No internal servic ing or re adjustment may b e
performed. If a pr oblem is enco untered, a nd you
determine the ECU to be faulty, contact the Polaris Service
Department for specific h andling instructions. Do not
replace the ECU without factory authorization.
The relationship between the ECU and the throttle position
sensor (TPS) is very critical to proper system operation. If
the TPS is faulty, or the mounting position of the TPS to the
throttle body is altered, the TPS must be adjusted.
For the purpose of troubleshooting, a kn own-good ECU
from an other Polaris
RANGER
RZR 57 0 of the same
model may be used without system or engine component
damage.
ECU