Theft Deterrent / Keyless Entry

Terminals Of Ecu

~3min read
TERMINALS OF ECU

1. CHECK MAIN BODY ECU (DRIVER SIDE JUNCTION BLOCK ASSEMBLY)

(a) Disconnect the main body ECU (driver side junction block assembly) connectors.


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

Tester Connection

Wiring Color

Terminal Description

Condition

Specified Condition

D49-7 (RCTY) - Body ground

GR - Body ground

Rear courtesy light switch RH input

Rear door RH closed (OFF) → open (ON)

10 kΩ or higher → Below 1 Ω

D49-21 (PCTY) - Body ground

V - Body ground

Passenger side courtesy light switch input

Passenger side door closed (OFF) → open (ON)

10 kΩ or higher → Below 1 Ω

D49-25 (BCTY) - Body ground

GR - Body ground

Back door courtesy light switch input

Back door closed (OFF) → open (ON)

10 kΩ or higher → Below 1 Ω

D50-16 (HCTY) - Body ground

BE - Body ground

Security courtesy switch

Engine hood closed (OFF) → open (ON)

10 kΩ or higher → Below 1 Ω

D50-24 (DCTY) - Body ground

V - Body ground

Driver side door courtesy light switch input

Driver side door closed (OFF) → open (ON)

10 kΩ or higher → Below 1 Ω

2A-1 (ACC) - Body ground

B - Body ground

Ignition power supply (ACC signal)

Engine switch on (ACC) → OFF

11 to 14 V → Below 1 V

2A-1 (IG) - Body ground

B - Body ground

Ignition power supply (IG signal)

Engine switch on (IG) → OFF

11 to 14 V → Below 1 V

2C-30 (ALTB) - Body ground

BR - Body ground

+B (power system alternator system) power supply

Always

11 to 14 V

2F-16 (GND1) - Body ground

W-B - Body ground

Ground

Always

Below 1 Ω

2C-24 (BECU) - Body ground

L - Body ground

+B power supply

Always

11 to 14 V

2C-24 (BECU) - Body ground

L - Body ground

+B power supply

Always

11 to 14 V

2O-19 (LCTY) - Body ground

R - Body ground

Rear courtesy light switch LH input

Rear door LH closed (OFF) → open (ON)

10 kΩ or higher → Below 1 Ω

If the result is not as specified, there may be a malfunction in the wire harness.

HINT:

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

(c) Reconnect the main body ECU (driver side junction block assembly) connectors.

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

Tester Connection

Wiring Color

Terminal Description

Condition

Specified Condition

D48-4 (HAZ) - Body ground

G - Body ground

Turn signal flasher relay signal

System in alarm sounding state

Below 1 V

D51-4 (IND) - Body ground

SB - Body ground

Security indicator output

Security indicator on

(It lights up only in arming preparation state or alarm sounding state. It flashes when immobiliser is operating.)

3 to 6 V

D51-6 (SH) - Body ground

BR - Body ground

Security horn drive

Security horn sounding

Pulse generation

(Below 1 V ← → 12 V)

2C-25 (HORN) - Body ground

R - Body ground

Vehicle horn drive

Vehicle horn sounding

(Theft deterrent system in alarm sounding state)

Pulse generation

(Below 1 V ← → 12 V)

If the result is not as specified, the main body ECU (driver side junction block assembly) may have a malfunction.

Test yourself

A quick Toyota Venza quiz: every answer comes with an explanation and a link to the manual page.