[Previous][Next]
DTC Description
CAN (Controller Area Network) is a serial communication line for real time applications. It is an on-vehicle multiplex communication line with high data communication speed and excellent error detection ability. Modern vehicle is equipped with many electronic control unit, and each control unit shares information and links with other control units during operation (not independent). In CAN communication, control units are connected with 2 communication lines (CAN-H line, CAN-L line) allowing a high rate of information transmission with less wiring. Each control unit transmits/receives data but selectively reads required data only.
 
 
DTC DETECTION LOGIC
DTC No.M.U.T.-III SE screen items
(Trouble diagnosis content)
DTC detection condition
U2140-87CAN comm err (ECM)
[Controller area network communication error (Engine control module)]
[MISSING MESSAGE]Diagnosis conditionWhen ignition switch is ON
Signal (terminal)CAN communication signal
ThresholdWhen IPDM E/R cannot communicate CAN communication signal
Diagnosis delay time2 seconds or more
 
 
POSSIBLE CAUSE
CAN communication system
 
 
FAIL-SAFE
When CAN communication with ECM is impossible, IPDM E/R performs fail-safe control. After CAN communication recovers normally, it also returns to normal control.
 
 
If No CAN Communication Is Available With ECM
Control partFail-safe operation
Cooling fan
  • The cooling fan is operated at HI operation when the ignition switch is turned ON.
  • Turn OFF the cooling fan operation when the ignition switch is turned OFF.
A/C compressorA/C compressor OFF
 
 
DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION PROCEDURE
With M.U.T.-III SE
  1. Ignition switch ON and wait for 2 seconds or more.
  2. Check “Self Diagnostic Result” of “IPDM E/R” using M.U.T.-III SE.
Is DTC detected?
-1 To check malfunction symptom before repair: Refer to Intermittent IncidentIntermittent Incident.
-2 Confirmation after repair: INSPECTION END