Component Location
General Description
Several control units are applied to electronically controlled vehicles. These units perform each control with informations from various sensors. Thus, sharing signal information from sensors is needed, so CAN communication type whose communication speed is high and insensitive to electrical noise by spark generation is adopted to controlling power-train(engine, atutomatic transaxle, ABS, TCS, ECS) As sharing signals of engine speed, APS, engaged gear and torque reduction through CAN communication, ECM and TCM modules control vehicle actively.
DTC Description
U0416 is set when ECM detects the signal requires abnormal torque increase from ECM for more than 0.5 sec. Checking CAN communication line or TCS module is required.
DTC Detecting Condition
Item | Detecting Condition | Possible Cause |
DTC Strategy | Signal monitoring
| CAN BUS CAN communication module component
|
Enable Conditions | IG KEY "ON"
|
Threshold Value | Abnormal torque increase request from TCS
|
Diagnostic Time | 500ms
|
Fail Safe | Fuel cut | NO | -
|
EGR Off | NO |
Fuel Limit | NO |
Check Lamp | NO |
Specification
Communication Format | DIGITAL "0" | DIGITAL "1"( BUS IDLE ) | CAN Communication Line Resistance |
HIGH | LOW | HIGH | LOW | Inside of ECM | Inside of I/P junction box |
CAN 2.0B | 3.5V | 1.5V | 2.5V | 2.5V | 120? (20?) | 120? (20?) |
Schematic Circuit Diagram
Signal Waveform & Data
Fig.1) CAN communication waveform
Monitoring CAN HIGH and LOW simultaneously is important in monitoring CAN communication waveform. When CAN HIGH signal rise to 3.5V and LOW signal drops to 1.5V - voltage difference between HIGH and LOW signal is 2V - at BUS IDLE state(DIGITAL "1") whose reference voltage is 2.5V, "0" is recognized. Besides, comparing HIGH and LOW signal if opposite waveform is detected with the reference voltage of 2.5V, Check if current cam signal transfers correctly.
Continuous "0"signal above 6BIT means the occurence of error in CAN communication. 1BIT is easily distinguished as calculating the time when "SOF"(START OF FRAME) which notifies the start of frame occurs. Check if "0"signal above 6BIT is detected continuously when monitoring CAN communication waveform.