Vehicle Exterior

Terminals Of Ecu

~2min read
TERMINALS OF ECU

1. CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY


(a) Disconnect the F42 air conditioning amplifier connector.

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

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

F42-21 (B) - F42-14 (GND)

V - W-B

Battery power source

Always

11 to 14 V

F42-1 (IG+) - F42-14 (GND)

L - W-B

Ignition power supply

Ignition switch ON

11 to 14 V

F42-1 (IG+) - F42-14 (GND)

L - W-B

Ignition power supply

Ignition switch off

Below 1 V

F42-14 (GND) - Body ground

W-B - Body ground

Ground

Always

Below 1 Ω

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

(c) Reconnect the F42 air conditioning amplifier connectors.

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

Terminal No. (Symbol)

Wiring Color

Terminal Description

Condition

Specified Condition

F42-40 (FDEF) - Body ground

LG - Body ground

Windshield deicer relay operation signal

Ignition switch ON, outer mirror heater switch off

11 to 14 V

F42-40 (FDEF) - Body ground

LG - Body ground

Windshield deicer relay operation signal

Ignition switch ON, outer mirror heater switch on

Below 1 V

F87-11 (FDF1) - Body ground

P - Body ground

Outer mirror heater switch indicator signal output

Ignition switch ON, outer mirror heater switch off

11 to 14 V

F87-11 (FDF1) - Body ground

P - Body ground

Outer mirror heater switch indicator signal output

Ignition switch ON, outer mirror heater switch on

Below 1 V

F87-5 (SW 1) - Body ground

R - Body ground

Outer mirror heater switch signal input

Ignition switch ON, outer mirror heater switch off

Below 1 V

F87-5 (SW 1) - Body ground

R - Body ground

Outer mirror heater switch signal input

Ignition switch ON, outer mirror heater switch on

11 to 14 V

  • If the result is not as specified, the air conditioning amplifier assembly may have a malfunction.

Test yourself

A quick Toyota 4Runner quiz: every answer comes with an explanation and a link to the manual page.