Toyota Yaris: Active Torque Split Awd System / Lost Communication with ECM/PCM "A" Missing Message (U010087,U012687,U012987)
DESCRIPTION
The AWD ECU assembly receives signals from the ECM, steering sensor and skid control ECU (brake actuator assembly) via CAN communication.
DTC No. | Detection Item | DTC Detection Condition | Trouble Area | Warning Indicate | Memory |
U010087 | Lost Communication with ECM/PCM "A" Missing Message | When the ignition switch is ON, the IG1 terminal voltage is 10 V or more and the vehicle speed is 60 km/h (37 mph) or more, signals cannot be received from the ECM for 1 second or more | -
CAN communication system
-
AWD ECU assembly
-
ECM
| Displayed | Yes |
U012687 | Lost Communication with Steering Angle Sensor Module Missing Message | -
When the following continues:
-
When the IG1 terminal voltage is 10 V or more, communication with the steering sensor is impossible for 1 second or more
-
When the IG1 terminal voltage is 10 V or more, a condition in which communication with the steering sensor is impossible occurs 1 time or more within a 5-second period, and this occurs 10 times within 60 seconds
| -
CAN communication system
-
AWD ECU assembly
-
Steering sensor
| Displayed | Yes |
U012987 | Lost Communication with Brake System Control Module Missing Message | When the IG1 terminal voltage is 10 V or more, communication with the skid control ECU (brake actuator assembly) is impossible for 3 seconds or more | -
CAN communication system
-
AWD ECU assembly
-
Skid control ECU (Brake actuator assembly)
| Displayed | Yes |
PROCEDURE
(a) Check for DTCs.
Click here
Chassis > Four Wheel Drive > Trouble Codes
(b) Record the output DTCs.
HINT:
When DTCs indicating a CAN communication system malfunction are output, repair the CAN communication system before repairing each corresponding sensor.
NEXT |
| GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING) |
DESCRIPTION When a malfunction has occurred in the power source circuit, the AWD ECU assembly stores DTC C123A1C. DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Memory C123A1C Supply Voltage Circuit Circuit Voltage Out of Range
At a vehicle speed of 3 km/h (2 mph) or more, the IG1 terminal voltage is less than 9...
DESCRIPTION The AWD ECU assembly is connected to the combination meter assembly via the CAN communication system. If the AWD ECU assembly stores any DTCs which are related to the active torque split AWD system, the warning message is displayed on the multi-information display in the combination meter assembly...
Other information:
COMPONENTS ILLUSTRATION
*1 FRONT FLOOR COVER LH *2 FRONT FLOOR COVER RH *3 FRONT NO. 1 FLOOR HEAT INSULATOR SUB-ASSEMBLY - -
N*m (kgf*cm, ft.*lbf): Specified torque - - ILLUSTRATION
*1 PROPELLER SHAFT WITH CENTER BEARING ASSEMBLY *2 CENTER NO...
TERMINALS OF ECU CHECK STEREO COMPONENT EQUALIZER ASSEMBLY
Terminal No. (Symbol) Terminal Description Condition Specified Condition O131-15(+B) - O131-30(GND) Power source Always 11 to 14 V O131-29(IGP) - O131-30(GND) Power source (IG) Ignition switch ON 11 to 14 V O131-14(ACC) - O131-30(GND) Power source (ACC) Ignition switch ACC 11 to 14 V O131-30(GND) - Body ground Ground Always Below 1 Ω O132-1(MC1+) - O131-30(GND) Active noise control microphone input signal Active noise control microphone LH tapped with finger Pulse generation O132-5(MC1-) - O131-30(GND) Active noise control microphone input signal Always Below 1 Ω O132-2(MC2+) - O131-30(GND) Active noise control microphone input signal Active noise control microphone RH tapped with finger Pulse generation O132-6(MC2-) - O131-30(GND) Active noise control microphone input signal Always Below 1 Ω O131-3(NEI) - O131-30(GND) Engine pulse signal Idling with warm engine Pulse generation (See waveform 1) O131-24(FLI-) Active noise control microphone output signal - - O131-9(FLI+) Active noise control microphone output signal - - O131-23(FRI-) Active noise control microphone output signal - - O131-8(FRI+) Active noise control microphone output signal - - O131-5(RRI+) Active noise control microphone output signal - - O131-20(RRI-) Active noise control microphone output signal - - O131-6(RLI+) Active noise control microphone output signal - - O131-21(RLI-) Active noise control microphone output signal - - O131-7(ASG1) Shield ground - - O131-22(ASG2) Shield ground - - O131-12(FR+) - O131-30(GND) Sound signal Active noise control system operating Pulse generation O131-27(FR-) - O131-30(GND) Sound signal Active noise control system operating Pulse generation O131-13(FL+) - O131-30(GND) Sound signal Active noise control system operating Pulse generation O131-28(FL-) - O131-30(GND) Sound signal Active noise control system operating Pulse generation O131-10(RR+) - O131-30(GND) Sound signal Active noise control system operating Pulse generation O131+25(RR-) - O131-30(GND) Sound signal Active noise control system operating Pulse generation O131-11(RL+) - O131-30(GND) Sound signal Active noise control system operating Pulse generation O131-28(RL-) - O131-30(GND) Sound signal Active noise control system operating Pulse generation O131-1(CANH) CAN communication signal - - O131-16(CANL) CAN communication signal - - (a) Waveform 1 HINT: The oscilloscope waveform shown in the illustration is an example for reference only...
Categories
Stop the vehicle completely.
Manual transaxle:
Shift into neutral and set the parking brake.
Automatic transaxle:
Shift the selector lever to the P position and set the parking brake.
Press the push button start to turn off the engine. The ignition position is
off.
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