Terminals Of Ecu
1. CHECK MAIN BODY ECU (DRIVER SIDE JUNCTION BLOCK ASSEMBLY)
(a) Disconnect the 2A, 2C and 2F main body ECU (driver side junction block assembly) connectors.
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(b) Measure the voltage and resistance according to the value(s) in the table below.
HINT:
Measure the values on the wire harness side with the connector disconnected.
Symbols (Terminal No.) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
2A-1 (ACC) - Body ground |
B - Body ground |
Ignition power supply (ACC signal) |
Ignition switch ACC → off |
10 to 14 V → Below 1 V |
2A-1 (IG) - Body ground |
B - Body ground |
Ignition power supply (IG signal) |
Ignition switch ON → off |
10 to 14 V → Below 1 V |
2C-24 (BECU) - Body ground |
L - Body ground |
+B power supply |
Always |
10 to 14 V |
2C-30 (ALTB) - Body ground |
BR - Body ground |
+B (power system alternator system) power supply |
Always |
10 to 14 V |
D51-5 (KSW) - Body ground |
L - Body ground |
Unlock warning switch input |
No key in ignition key cylinder (OFF) → Key inserted (ON) |
10 kΩ or higher → Below 1 Ω |
2F-16 (GND1) - 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 2A, 2C and 2F main body ECU (driver side junction block assembly) connectors.
(d) Measure the voltage according to the value(s) in the table below.
Symbols (Terminal No.) | Wiring Color | Terminal Description | Condition | Specified Condition |
|---|---|---|---|---|
D50-24 (DCTY) - Body ground |
V - Body ground |
Driver side door courtesy light switch input |
Driver side door CLOSED (OFF) → OPEN (ON) |
Pulse generation → Below 1 V |
D49-21 (PCTY) - Body ground |
V - Body ground |
Passenger side courtesy light switch input |
Passenger side door CLOSED (OFF) → OPEN (ON) |
Pulse generation → Below 1 V |
D49-7 (RCTY) - Body ground |
GR - Body ground |
Rear courtesy light switch RH input |
Rear door RH CLOSED (OFF) → OPEN (ON) |
Pulse generation → Below 1 V |
2O-19 (LCTY) - Body ground |
R - Body ground |
Rear courtesy light switch LH input |
Rear door LH CLOSED (OFF) → OPEN (ON) |
Pulse generation → Below 1 V |
D49-25 (BCTY) - Body ground |
GR - Body ground |
Back door courtesy light switch input |
Back door CLOSED (OFF) → OPEN (ON) |
Pulse generation → Below 1 V |
D48-4 (HAZ) - Body ground |
G - Body ground |
Turn signal flasher relay signal |
Any transmitter switch pressed → not pressed |
Below 1 V → 10 to 14 V |
2C-25 (HORN) - Body ground |
R - Body ground |
Vehicle horn signal |
Vehicle horn is sounding (Panic alarm system is in alarm sounding state) |
Below 1 V ← → 12 V |
D51-7 (BZR) - Body ground |
LG - Body ground |
Wireless door lock buzzer signal |
Wireless door lock buzzer OFF → ON |
Below 1 V → Pulse generation |
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.