MULTI-MODE MANUAL TRANSAXLE SYSTEM, Diagnostic DTC:P0885, P0887

DTC Code DTC Name
P0885 TCM Power Relay Control Circuit / Open
P0887 TCM Power Relay Control Circuit (Short)

DESCRIPTION

The multi-mode manual transmission system has a dedicated power supply circuit. While the ignition switch is turned to ON, the transmission control ECU outputs the power from the MREL terminal to operate the MMT relay. Then, the power is supplied to the +BM terminal of the transmission control ECU through the MMT relay. The voltage (+BM) is monitored and when it is low (6.29 V or less) despite the voltage is supplied to MREL circuit, the transmission control ECU determines that there is a malfunction in the multi-mode manual transmission system and sets a DTC. When the voltage (+BM) is high (6.29 V or more) although the voltage is not supplied to the MREL circuit, the transmission control ECU sets a DTC.

DTC No. DTC Detecting Conditions Trouble Areas
P0885

The transmission control ECU detects the following conditions simultaneously:

(1 trip detection logic)


  1. Voltage is supplied to MREL circuit

  2. +BM voltage is less than 6.29 V for 0.5 seconds

  • AMT fuse

  • MMT relay

  • Open in MREL signal circuit

  • Open in PGND signal circuit

  • Open in +BM signal circuit

  • Transmission control ECU
P0887

The transmission control ECU detects the following conditions simultaneously:

(1 trip detection logic)


  1. No voltage is supplied to MREL circuit

  2. +BM voltage is more than 6.29 V for 0.5 seconds

  • MMT relay

  • Short in MREL signal circuit

  • Short in PGND signal circuit

  • Short in +BM signal circuit

  • Transmission control ECU

WIRING DIAGRAM

A01383EE02

INSPECTION PROCEDURE

PROCEDURE


  1. INSPECT RELAY

    A01380OE02

    1. Remove the MMT relay from the engine room R/B No. 2.

    2. Check the resistance.

      Standard Resistance
      Tester Connections Specified Conditions
      3 - 5 10 kΩ or higher
      3 - 5

      Below 1 Ω

      When battery voltage applied to terminal 1 and 2

    3. Reinstall the MMT relay.


    NG

    REPLACE RELAY

    OK

  2. INSPECT TRANSMISSION CONTROL ECU ASSEMBLY (+BM TERMINAL INPUT VOLTAGE)

    A013645E01

    1. Disconnect the transmission control ECU connector.

    2. Turn the ignition switch to ON.

    3. Measure the voltage between the terminals of the transmission control ECU connector.

      Standard Voltage
      Tester Connections Specified Conditions
      +BM (A29-2) - PGND (A29-8) 10 to 14 V

    4. Turn the ignition switch to OFF.

    5. Measure the voltage between the terminals of the transmission control ECU connector.

      Standard Voltage
      Tester Connections Specified Conditions
      +BM (A29-2) - PGND (A29-8) Below 1 V

    6. Reconnect the transmission control ECU connector.


    OK

    REPLACE TRANSMISSION CONTROL ECU ASSEMBLY

    NG

  3. INSPECT TRANSMISSION CONTROL ECU ASSEMBLY (MREL TERMINAL OUTPUT VOLTAGE)

    A0135VXE06

    1. Measure the voltage between the terminal of the transmission control ECU and the body ground when the ignition switch is turned to ON and OFF.

      Standard Voltage
      Tester Connections Ignition Switch Specified Conditions

      MREL (A28-5) - Body

      ground

      		 OFF Below 1 V

      MREL (A28-5) - Body

      ground

      		 ON 10 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT BETWEEN MREL AND GND) Click here

    OK

    REPAIR OR REPLACE HARNESS AND CONNECTOR (MREL - MMT RELAY - GND, +BM - MMT RELAY - BATTERY)

  4. CHECK HARNESS AND CONNECTOR (CHECK FOR SHORT BETWEEN MREL AND GND)

    A0136IKE05

    1. Disconnect the transmission control ECU connectors.

    2. A0138C3E01

      Remove the MMT relay from the engine room R/B No. 2.

    3. Check the resistance.

      Standard Resistance (Check for Short)
      Tester Connections Specified Conditions
      MREL (A28-5) - Body ground 10 kΩ or higher

    4. Reconnect the transmission control ECU connectors.

    5. Reinstall the relay.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE TRANSMISSION CONTROL ECU ASSEMBLY