Component Location
General Description
In EURO4 diesel engine with CPF, injection is devided into 2 pilot, 1 main, 2 post injections. Among these injections, pilot and main injections are for the operation of engine, however post injections are for CPF regeneration. Only in activating condition of CPF regeneration during driving, post injection starts. 1st post injection happens at the end of combustion cycle then, injected fuel is used to raise exhaust temperature. that temp. is sensed at T3 exhaust tempt. sensor which is ahead of Turbo charger. 2nd post injection happens at exhaust cycle then, injected fuel is also used to raise exhaust temperature. that temp. is sensed T5 exhaust tempt. sensor which is between Oxydation catalyst and CPF. The reason of raising exhaust tempt. is because exhaust tempt. in diesel engine is too low for CPF regeneration. The optimum tempt. for CPF regeneration is 550~600? thus, the goal of post injection is raise exhaust tempt. to that range of tempt.. However if exhaust tempt. is too high, turbo charger or CPF are likely to be damaged. Therefore if tempt. measured at each sensor is out of permittable value(specification), ECM deactivates CPF regeneration.
DTC Description
P0545 is set when front exhaust gas temp. sensor(T3-VGT) signal voltage is below 0.2V - the lower limit value - for more than 0.6 sec.
DTC Detecting Condition
Item | Detecting Condition | Possible Cause |
DTC Strategy | Voltage monitoring
| Exhaust gas temp. sensor(T3-VGT) wiring
Exhaust gas temp. sensor(T3-VGT) component
|
Enable Conditions | IG KEY "ON" or Engine running
|
Threshold Value | Signal voltage below 0.2V(Short to ground in signal circuit)
|
Diagnostic Time | 0.6 sec.
|
Fail Safe | Fuel cut | NO |
-
|
EGR Off | NO |
Fuel Limit | NO |
Check Lamp | NO |
Specification
Resistance/Temperature Characteristics
Temp. (?) | Nominal (k?) | NEW | AGED |
Min(k?) | Max(k?) | Min(k?) | Max(k?) |
100 | 371 | 289 | 481 | 272 | 515 |
300 | 5.92 | 5.3 | 6.61 | 5.15 | 6.79 |
600 | 0.363 | 0.347 | 0.379 | 0.341 | 0.386 |
900 | 0.0893 | 0.0842 | 0.0949 | 0.0833 | 0.096 |
Schematic Circuit Diagram
Signal Waveform & Data
Fig.1) 4.8V is outputted at EGTS output signal circuit, when exhaust gas temp. is approx.150?.
when exhaust gas temp. is 550~600? at CPF regeneration, output voltage drops to 0.3~0.4V.