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 switch power supply |
Ignition switch ON |
11 to 14 V |
F42-1 (IG+) - F42-14 (GND) |
L - W-B |
Ignition switch 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 connector.
(d) Measure the voltage according to the value(s) in the table below.
Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
F42-38 (RDEF) - F42-14 (GND) |
P - W-B |
Rear defogger signal |
Ignition switch ON, rear window defogger switch off |
11 to 14 V |
F42-38 (RDEF) - F42-14 (GND) |
P - W-B |
Rear defogger signal |
Ignition switch ON, rear window defogger switch on |
Below 1 V |
- If the result is not as specified, there may be a malfunction in the air conditioning amplifier.
2. CHECK HEATER CONTROL ASSEMBLY
(a) Disconnect the F29 heater control connector.
(b) Measure the resistance and voltage according to the value(s) in the table below.
Terminal No. (Symbol) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
F29-4 (IG+) - F29-11 (GND) |
L - W-B |
Ignition switch power supply |
Ignition switch ON |
11 to 14 V |
F29-4 (IG+) - F29-11 (GND) |
L - W-B |
Ignition switch power supply |
Ignition switch off |
Below 1 V |
F29-11 (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.
Test yourself
A quick Toyota 4Runner quiz: every answer comes with an explanation and a link to the manual page.