Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM100000001HAPU
Model Year Start: 2020 Model: GR Corolla Prod Date Range: [01/2019 - 06/2021]
Title: THEFT DETERRENT / KEYLESS ENTRY: THEFT DETERRENT SYSTEM (for Gasoline Model): TERMINALS OF ECU; 2020 - 2021 MY Corolla Corolla Hatchback GR Corolla [01/2019 - 06/2021]

TERMINALS OF ECU

CHECK MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) AND INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

(a) Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

Click here 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL 2020 - 2022 MY Corolla Corolla Hatchback Corolla HV GR Corolla [03/2019 - 09/2022]; POWER DISTRIBUTION: MAIN BODY ECU: REMOVAL

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

HINT:

Measure the values on the wire harness side with the connectors connected.

Terminal No. (Symbol)

Wiring Color

Input/Output

Terminal Description

Condition

Specified Condition

Related Data List Item

I86-19 (GND2) - Body ground

W-B - Body ground

-

Ground

Always

Below 1 Ω

-

(c) Reconnect the instrument panel junction block assembly connectors.

(d) Measure the resistance and voltage according to the value(s) in the table below.

HINT:

Measure the values on the wire harness side with the connectors connected.

Terminal No. (Symbol)

Wiring Color

Input/Output

Terminal Description

Condition

Specified Condition

Related Data List Item

MB-31 (BECU) - Body ground

-

Input

Battery power supply

Always

11 to 14 V

-

MB-32 (IG) - Body ground

-

Input

Ignition power supply (IG signal)

Ignition switch off

Below 1 V

IG SW

Ignition switch ON

11 to 14 V

MB-30 (ACC) - Body ground

-

Input

Ignition power supply (ACC signal)

Ignition switch off

Below 1 V

ACC SW

Ignition switch ACC

11 to 14 V

MB-11 (GND1) - Body ground

-

-

Ground

Always

Below 1 Ω

-

I85-1 (FLCY) - Body ground

BR - Body ground

Input

Front door courtesy light switch assembly (for LH) input

Front door LH closed

10 kΩ or higher

FL Door Courtesy SW

Front door LH open

Below 1 Ω

I85-6 (FRCY) - Body ground

SB - Body ground*1

BR - Body ground*2

Input

Front door courtesy light switch assembly (for RH) input

Front door RH closed

10 kΩ or higher

FR Door Courtesy SW

Front door RH open

Below 1 Ω

MB-13 (LCTY) - Body ground

-

Input

Rear door courtesy light switch assembly (for LH) input

Rear door LH closed

10 kΩ or higher

RL Door Courtesy SW

Rear door LH open

Below 1 Ω

MB-2 (RCTY) - Body ground

-

Input

Rear door courtesy light switch assembly (for RH) input

Rear door RH closed

10 kΩ or higher

RR Door Courtesy SW

Rear door RH open

Below 1 Ω

I85-30 (HCTY) - Body ground

R - Body ground

Input

Engine hood courtesy switch input

Engine hood open

10 kΩ or higher

Hood Courtesy SW

Engine hood closed

Below 1 Ω

MB-4 (LGCY) - Body ground*1

-

Input

Luggage compartment door courtesy light switch input

Luggage compartment door closed

10 kΩ or higher

Luggage Courtesy SW

Luggage compartment door open

Below 1 Ω

MB-4 (BCTY) - Body ground*2

-

Input

Back door courtesy light switch input

Back door closed

10 kΩ or higher

Back Door Courtesy SW

Back door open

Below 1 Ω

MB-14 (TRLY) - Body ground

-

Output

Taillight relay drive output

Always

11 to 14 V

-
  • *1: for Sedan
  • *2: for Hatchback

(e) Install the main body ECU (multiplex network body ECU) to instrument panel junction block assembly.

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(f) Measure the voltage and check for pulses according to the value(s) in the table below.

Terminal No. (Symbol)

Wiring Color

Input/Output

Terminal Description

Condition

Specified Condition

Related Data List Item

4F-13 (LSFL) - Body ground

SB - Body ground*1

L - Body ground*2

Input

Front door LH unlock detection switch input

Front door LH unlocked

Below 1 V

FL Door Lock Pos SW

Front door LH locked

11 to 14 V or pulse output (maximum 14 V)*5

4F-12 (LSFR) - Body ground

BR - Body ground

Input

Front door RH unlock detection switch input

Front door RH unlocked

Below 1 V

FR Door Lock Pos SW

Front door RH locked

11 to 14 V or pulse output (maximum 14 V)*5

I84-18 (L2) - Body ground

G - Body ground

Input

Driver door key-linked lock input

Driver door key cylinder turned to lock position

Below 1 V

Door Key SW-Lock

Driver door key cylinder off

11 to 14 V

I84-17 (UL3) - Body ground

V - Body ground

Input

Driver door key-linked unlock input

Driver door key cylinder turned to unlock position

Below 1 V

D Door Key SW-UL

Driver door key cylinder off

11 to 14 V

4F-14 (LSR) - Body ground

GR - Body ground*1

LG - Body ground*2

Input

Rear door LH/RH unlock detection switch input

Rear door LH or RH unlocked

Below 1 V
  • RR-Door Lock Pos SW
  • RL-Door Lock Pos SW

Rear door LH and RH locked

11 to 14 V or pulse output (maximum 14 V)*5

4B-26 (SH) - Body ground

Y - Body ground

Output

Security horn assembly drive

Security horn assembly sounding

(Theft deterrent system in alarm sounding state)

Pulse generation

(Below 1 V ← → 11 to 14 V)

-

4B-27 (HORN) - Body ground

L - Body ground

Output

Vehicle horn drives

Vehicle horn sounding

(Theft deterrent system in alarm sounding state)

Pulse generation

(Below 1 V ← → 11 to 14 V)

-

4B-31 (HRLY) - Body ground

G - Body ground*1, *3

B - Body ground*4

Input

H-LP LH relay drive output

Low beams blinking

(Theft deterrent system in alarm sounding state)

Pulse generation (Below 1 V ← → 11 to 14 V)

-

I85-12 (HRY2) - Body ground

G - Body ground

Input

H-LP RH relay drive output

Low beams blinking

(Theft deterrent system in alarm sounding state)

Pulse generation (Below 1 V ← → 11 to 14 V)

-

4F-29 (ILE) - Body ground

V - Body ground

Output

Interior lights drive output

Interior lights illuminated

(Theft deterrent system in alarm sounding state)

Below 1 V

-
  • *1: for Sedan
  • *2: for Hatchback
  • *3: for Hatchback with AFS
  • *4: for Hatchback without AFS
  • *5: Differs depending on the vehicle model