Component Location
General Description
ECM is activated by power supply. Signals from several sensors, such as CKPS and APS, is inputted to ECM. Comparing inputted siganals with control LOGIC saved at micro controller and EEPROM, ECM controlls engine as actuating injectors, solenoids and relays.
To guarantee accurate control, ECM performs SELF TEST, DIAGNOSIS of several sensors and actuators. And if serious trouble which affects vehicle performance occurrs, ECM sets DTCs.
At certain cases, ECM shuts down whole systems in order to prevent dangerous situation due to incorrect control.
DTC Description
P0643 is set when the voltage in 'Power #1,#2,#3' circuit is above upper limit for more than 0.12 sec.. This code is due to the short to battery in sensor power circuit or the voltage problem inside of ECM.
DTC Detecting Condition
Item | Detecting Condition | Possible Cause |
DTC Strategy | Voltage monitoring
| APS 2 power supply circuit APT power supply circuit DPS power supply circuit ECM component
|
Enable Conditions | IG KEY "ON"
|
Threshold Value | When the voltage is above the maximum voltage of sensor power supply.
|
Diagnostic Time | 100ms
|
Fail Safe | Fuel Cut | NO | |
EGR Off | NO |
Fuel Limit | YES |
MIL | NO |
Specification
Sensor power 1 | Sensor power 2 | Sensor power 3 |
APS 2 | ACV | RPS |
APT | BPS |
DPS | CAM |
VSA | APS 1 |
4830mV~5158mV | 4830mV~5158mV | 4830mV~5158mV |
Diagnostic Circuit Diagram