ECM controls injection amount and injection timing through Electrical control injector in order to control system pressure which is required for measuring and injection of diesel fuel. Injectors on CRDi injects atomized fuel with highly pressurized directly into the combustion chamber corresponding to fuel amount ECM decided. Fuel injected into combustion chamber generates power through the explosion.
There are 2 different fuel injection on the S engine. One is 2 time pilot injection for reducing explosion noise during fuel control, another is main injection for generating power. In addition, those are controlled independently by ECM and injection time (injection amount) as well. Injector is newly adopted new technology. that are hydraulic coupler which transfer operating force of actuator as quickly as possible and PIEZO actuator what is operating response better than solenoid actuator. Both PIEZO actuator and hydraulic coupler realized to increase the fuel pressure to 250 ~ 1600bar. That makes high combustion efficiency resulting to reduced smog and improved engine power and fuel efficiency.
Inputting IQA code of injectors installed in each cylinder to ECM, ECM recognizes the fuel injection quantity difference between each injectors. ECM adjusts every injector to have same fuel injecting characteristic as recognizing specific fuel injection map which is different for each serial number.
【IQA, Injector Quantity Adjustment】IQA means adjusting fuel injection quantity difference between injectors which occurs inevitably at manufacturing process as allotting serial number consists of 7 letters to each injectors.
DTC P0277 is set when short to battery is detected in "High side" circuit or "Low side" circuit of injector #6at injection condition. This code is due to battery to ground in injector #6circuit / injector component. ECM detects failure as injector driving voltage of injector #6circuit.
Item | Detecting Condition | Possible Cause | ||
DTC Strategy |
•
Current Monitoring |
•
Injector circuit
•
Injector component | ||
Enable Conditions |
•
IG key ON | |||
Threshold Value |
•
Short to battery in High side circuit.
•
Short to battery in Low side circuit. | |||
Diagnostic Time |
•
Immediately | |||
Fail Safe | Fuel cut | YES |
•
MIL is blinking if no IQA inputted. | |
EGR Off | NO | |||
Fuel Limit | NO | |||
Check Lamp | ON |
Control Type | Component Resistance | Operating Voltage |
PIEZO voltage control | 150 ~250 kΩ (20℃) | 100V ~ 200V(100V ~ 140V at 250bar) |
Fig.1) Signal waveform of Injector at idle.