SFI SYSTEM, Diagnostic DTC:P1543

DTC Code DTC Name
P1543 Short Circuit to Ground / Batt of the AC Compressor

DESCRIPTION

When the ECM is turned on, a magnetic clutch on signal is sent from the MGC terminal of the ECM. Then, the MG CLUTCH relay turns on to operate the compressor with magnet clutch.

DTC No.

Detection Item

DTC Detection Condition

Trouble Area

MIL

Memory

P1543

Short Circuit to Ground / Batt of the AC Compressor

Open or short in compressor with magnet clutch circuit.

  • Compressor with magnet clutch circuit

  • MG CLUTCH relay

  • Compressor with magnet clutch

  • ECM

Does not Come on

DTC stored

MONITOR DESCRIPTION

This DTC is stored when a malfunction is detected in the compressor with magnet clutch circuit. If there is an open or short in the compressor with magnet clutch circuit, the ECM will store this DTC.

WIRING DIAGRAM

A327742E01

CAUTION / NOTICE / HINT

Note:

Inspection the fuses for circuits related to this system before performing the following procedure.

PROCEDURE

  1. INSPECT MG CLUTCH RELAY

    1. Inspect the MG CLUTCH relay.

      Click here

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE MG CLUTCH RELAY

    OK

  2. CHECK HARNESS AND CONNECTOR (MG CLUTCH RELAY - ECM)

    1. Remove the MG CLUTCH relay from the No. 2 engine room relay block.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      2 (MG CLUTCH relay) - A35-27 (MGC)

      Always

      Below 1 Ω

      2 (MG CLUTCH relay) or A35-27 (MGC) - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK TERMINAL VOLTAGE (POWER SOURCE OF MG CLUTCH RELAY)

    1. Remove the MG CLUTCH relay from the No. 2 engine room relay block.

    2. Turn the ignition switch to ON.

    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      1 (MG CLUTCH relay) - Body ground

      Ignition switch ON

      11 to 14 V

      5 (MG CLUTCH relay) - Body ground

      Ignition switch ON

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

    CHECK POWER SOURCE CIRCUIT (MG CLUTCH RELAY POWER SOURCE CIRCUIT)

    for Automatic Air Conditioning System:Click here

    for Manual Air Conditioning System:Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (MG CLUTCH RELAY - COMPRESSOR WITH MAGNET CLUTCH)

    1. Remove the MG CLUTCH relay from the No. 2 engine room relay block.

    2. Disconnect the compressor with magnet clutch connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      3 (MG CLUTCH relay) - C3-1 (MG+)

      Always

      Below 1 Ω

      3 (MG CLUTCH relay) or C3-1 (MG+) - Body ground and other terminals

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (COMPRESSOR WITH MAGNET CLUTCH - BODY GROUND)

    1. Disconnect the compressor with magnet clutch connector.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      C3-2 (MG-) - Body ground

      Always

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. REPLACE COMPRESSOR WITH MAGNET CLUTCH

    1. Replace the compressor with magnet clutch.

      Click hereClick here

    Result

    Proceed to

    NEXT
    NEXT

  7. CHECK WHETHER DTC OUTPUT RECURS (DTC P1543)

    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Clear the DTCs.

      Powertrain > Engine > Clear DTCs

    5. Turn the ignition switch off and wait for a few minutes.

    6. Perform the drive test.

    7. Turn the GTS on.

    8. Enter the following menus: Powertrain / Engine / Trouble Codes.

    9. Check for DTCs.

      Powertrain > Engine > Trouble Codes

    Result

    Result

    Proceed to

    DTC P1543 is output

    A

    DTCs are not output

    B
    A

    REPLACE ECM

    Click here

    B

    END