Toyota Tacoma manuals

Toyota Tacoma (2015-2018) Service Manual: Lost Communication with ECM/PCM "A" Missing Message (U010087)

Toyota Tacoma (2015-2018) Service Manual / Ac60e Automatic Transmission / Transaxle / Automatic Transmission System(for 2gr-fks) / Lost Communication with ECM/PCM "A" Missing Message (U010087)

DESCRIPTION

The engine control unit and the transmission control unit are located inside the ECM. The engine control unit intercommunicates with the transmission control unit with the Controller Area Network (CAN).

If there is a problem in this intercommunication, the ECM stores a DTC.

DTC Code

DTC Detection Condition

Trouble Area

SAE

U010087

All conditions are met for 1.25 seconds or more (1-trip detection logic):

(A) The ignition switch is ON and battery voltage is 9.5 V or higher.

(B) There is no communication between the engine control unit and transmission control unit.

ECM

U0100

MONITOR STRATEGY

Related DTCs

U0100: Verify communication

Required Sensors/Components (Main)

ECM

Required Sensors/Components (Related)

-

Frequency of Operation

Continuous

Duration

1.25 seconds

MIL Operation

Immediate

Sequence of Operation

None

TYPICAL ENABLING CONDITIONS

Monitor runs whenever following DTCs not stored

None

Battery Voltage

9.5 V or higher

Ignition Switch

ON

Starter

OFF

TYPICAL MALFUNCTION THRESHOLDS

Communication signal

Lost communication with engine control unit

CONFIRMATION DRIVING PATTERN

HINT:

  • After repairs have been completed, clear the DTCs and then check that the vehicle has returned to normal by performing the following All Readiness check procedure.
  • When clearing the permanent DTCs, refer to the Clear Permanent DTC procedure (See page ).
  1. Connect the Techstream to the DLC3.
  2. Turn the ignition switch to ON and turn the Techstream on.
  3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC procedure).
  4. Turn the ignition switch off and wait for 2 minutes or more.
  5. Turn the ignition switch to ON and turn the Techstream on.
  6. Wait for 2 seconds or more with the ignition switch to ON. [*1]

    HINT:

    [*1] : Normal judgment procedure.

    The normal judgment procedure is used to complete DTC judgment and also used when clearing permanent DTCs.

  7. Enter the following menus: Powertrain / Transmission / Utility / All Readiness.
  8. Input the DTC: U010087.
  9. Check the DTC judgment result.

    Techstream Display

    Description

    NORMAL
    • DTC judgment completed
    • System normal

    ABNORMAL
    • DTC judgment completed
    • System abnormal

    INCOMPLETE
    • DTC judgment not completed
    • Perform driving pattern after confirming DTC enabling conditions

    N/A
    • Unable to perform DTC judgment
    • Number of DTCs which do not fulfill DTC preconditions has reached ECU memory limit

    HINT:

    • If the judgment result shows NORMAL, the system is normal.
    • If the judgment result shows ABNORMAL, the system has a malfunction.
    • If the judgment result shows INCOMPLETE or N/A, perform the normal judgment procedure again.

CAUTION / NOTICE / HINT

NOTICE:

  • Perform the universal trip to clear permanent DTCs (See page Perform registration and/or initialization when parts related to the ).
  • Perform registration and/or initialization when parts related to the automatic transmission are replaced (See page )

PROCEDURE

1.

CHECK DTC OUTPUT (IN ADDITION TO DTC U010087)

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Powertrain / Transmission / Trouble Codes.

(e) Read the DTCs using the Techstream.

Result

Result

Proceed to

Only U010087 is output

A

U010087 and other DTCs are output

B
A

REPLACE ECM

B

GO TO DTC CHART

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