Terminals Of Ecu
- CHECK AIR CONDITIONING AMPLIFIER (A/C ECU)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Disconnect the K52 ECU connector.
- Measure the resistance and voltage of the wire harness side connector.
Standard resistance
TERMINALS RESISTANCE REFERENCESymbols (Terminal No.) Wiring Color Terminal Description Specified Condition GND (K52-20) - Body ground W-B - Body ground Ground Below 1 Ω Standard voltage
TERMINALS VOLTAGE REFERENCESymbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition B (K52-1) - GND (K52-20) L - W-B Battery Always 10 to 14 V IG+ (K52-21) - GND (K52-20) W - W-B IG power supply Power switch OFF Below 1 V IG+ (K52-21) - GND (K52-20) W - W-B IG power supply Power switch ON (IG) 10 to 14 V If the result is not as specified, there may be a malfunction on the wire harness side.
- Reconnect the K52 ECU connector.
- Measure the voltage of the connector.
Standard voltage
TERMINALS VOLTAGE REFERENCESymbols (Terminal No.) Wiring Color Terminal Description Condition Specified Condition LOUT (K51-16) - GND (K52-20) SB - W-B Driver side climate control seat blower operation signal Power switch ON (IG), front LH side seat heater switch blower side ON (blower volume 3) Pulse generation (see WAVEFORM 1 ) ROUT (K51-8) - GND (K52-20) O - W-B Front passenger side climate control seat blower operation signal Power switch ON (IG), front RH side seat heater switch blower side ON (blower volume 3) Pulse generation (see WAVEFORM 1 ) If the result is not as specified, the ECU may have a malfunction.
- Using an oscilloscope, check the waveform.
Waveform 1 (reference)
WAVEFORM REFERENCEItem Content Symbols (Terminal No.) LOUT (K51-16) or ROUT (K51-8) - GND (K52-20) Tool Setting 2 V/DIV., 500 μsec/DIV. Condition Power switch ON (IG)