Terminals Of Ecu

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.

CHECK MAIN BODY ECU RH (COWL SIDE JUNCTION BLOCK RH)

Disconnect the main body ECU RH (cowl side junction block RH) connectors

Fig 1: Identifying Connector Location
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the resistance and voltage of the wire harness side connectors.

RESISTANCE REFERENCE

Tester Connection	Wiring Color	Terminal Description	Condition	Specified Condition
J75-23 (PCTY) - Body ground	B - Body ground	Passenger side courtesy light switch input	Passenger side door CLOSED (OFF) → OPEN (ON)	10 kΩ or higher → Below 1 Ω
J75-25 (LGCY) - Body ground	L - Body ground	Luggage compartment door courtesy light switch input	Luggage compartment door CLOSED (OFF) → OPEN (ON)	10 kΩ or higher → Below 1 Ω
P1-14 (DCTY) - Body ground	W - Body ground	Driver side door courtesy light switch input	Driver side door CLOSED (OFF) → OPEN (ON)	10 kΩ or higher → Below 1 Ω
P1-16 (RCTY) - Body ground	O - Body ground	Rear courtesy light switch RH input	Rear door RH CLOSED (OFF) → OPEN (ON)	10 kΩ or higher → Below 1 Ω
RA-5 (GND2) - Body ground	W-B - Body ground	Ground	Always	Below 1 Ω
RA-11 (LCTY) - Body ground	BR - Body ground	Rear courtesy light switch LH input	Rear door LH CLOSED (OFF) → OPEN (ON)	10 kΩ or higher → Below 1 Ω
RM-1 (ALTB) - Body ground	B - Body ground	+B (power generator system) power supply	Always	11 to 14 V
RD-7 (GND2) - Body ground	W-B - Body ground	Ground	Always	Below 1 Ω
RK-5 (BECU) - Body ground	G-R - Body ground	+B power supply	Always	11 to 14 V
RN-1 (BATB) - Body ground	R - Body ground	+B (power battery system) power supply	Always	11 to 14 V

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

Reconnect the main body ECU RH (cowl side junction block RH) connectors.

Measure the voltage of the wire harness side connectors.

VOLTAGE SPECIFICATION

Tester Connection	Wiring Color	Terminal Description	Condition	Specified Condition
A36-1 (SH) - Body ground	W - Body ground	Security horn drive	Security horn is sounding (Theft deterrent system is in alarm sounding state)	Pulse generation Below 1 V ← → 11 to 14 V
J74-2 (HAZ) - Body ground	Y - Body ground	Hazard warning light signal	Hazard warning lights are blinking (Theft deterrent system is in alarm sounding state)	Pulse generation Below 1 V ← → 11 to 14V
J74-24 (IND) - Body ground	LG - Body ground	Security indicator output	Security indicator light up (It lights up only for 30 sec in alarm sounding state It flashes when immobilizer is operating)	3 to 6V

CHECK ENGINE ROOM NO. 2 RELAY BLOCK AND JUNCTION BLOCK ASSEMBLY (FRONT CONTROLLER)

Disconnect the 2G multiplex network body ECU connector

Fig 2: Identifying 2G Multiplex Network Body ECU Connector
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Measure the resistance between each terminal of the wire harness connector and body ground

RESISTANCE REFERENCE

Tester Connection	Wiring Color	Terminal Description	Condition	Specified Condition
2G-3 - Body ground	W-L - Body ground	Engine hood courtesy switch	Engine hood CLOSED (OFF) → OPEN (ON)	10 kΩ or higher → Below 1 Ω

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

Reconnect the 2G multiplex network body ECU connector.

Measure the voltage between each terminal of the connector and body ground

VOLTAGE SPECIFICATION

Tester Connection	Wiring Color	Terminal Description	Condition	Specified Condition
2G-1 - Body ground	B - Body ground	Vehicle horn drive	Vehicle horn is sounding (Theft deterrent system is in alarm sounding state)	Pulse generation (Below 1 V ← → 11 to 14 V)
2G-2 - Body ground	B-R - Body ground	Vehicle horn drive	Vehicle horn is sounding (Theft deterrent system is in alarm sounding state)	Pulse generation (Below 1 V ← → 11 to 14 V)