Multec 3.5 Injectors - Hisun HS700UTV-4 Maintenance Handbook

2．Handling – DOs & DONTs
ECU Handing
ACTION
DO NOT: Place the ECU close to the exhaust
pipe or Engine when removed
DO NOT: Place the ECU close to or pour
water, oil or any other liquids.
DO NOT: Allow mud or other debris to
accumulate on the surface of the ECU
DO NOT: Apply any voltage relative to any
point to the ECU
DO NOT: Clean ECU with any solvent or any
corrosive liquid
DO: Take extreme care that water droplets or
excess moisture should not fall on ECU
connectors
DO: Clean the ECU with a moist cloth and
keep it dry
3．Installation requirements
The ECU shall be mounted using M5 machined screws with a torque of 3.9Nm ± 10%. The
mounting surface should also be flat to avoid subjecting the base plate to unnecessary force and
warping the PCB.
4．Maintenance service and Repair
ECU is a non-serviceable part. Once there are problems, it's important to first determine if the
problem is caused by software/calibration. If it is caused by software/calibration, please refer to
software/calibration reflashing procedure. In the event of ECU hardware failure or malfunction
(during warranty period only) the ECU should be sent back to the vehicle manufacturer giving
complete details of the ECU Part No, Serial number, Vehicle Model & Make, manufacturing Date,
Total kms run on the vehicle, Location of use, Vehicle No, Date of return.

Multec 3.5 Injectors

1．Description and Working Principle
The Multec 3.5 Fuel Injector is an electromechanical device. A magnetic field is generated as
voltage is applied to the solenoid coil.
The resulting magnetic force lifts the core assembly, overcoming manifold vacuum, spring force,
and fuel pressure, allowing fuel to pass through the ball and seat interface to the director.
As the fuel passes through the director, an atomized spray is developed. The injector closes
when the voltage is removed, cutting off the fuel flow.
ENGINE MANAGEMENT SYSTEM
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REASON
High temperature might reduce the life of the
ECU and also can damage the ECU
ECU is susceptible to water and liquids
Having mud or debris accumulated on the
ECU casing reduces its heat dissipation
efficiency.
Drastically affects the performance of the
ECU and may lead to ECU damage
Can damage the housing of the ECU
ECU connectors can get short and may
lead to ECU damage
Prevents ECU damage