Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Terminals Of Ecu
- CHECK FRONT LIGHT ECU (FRONT CONTROLLER)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Measure the resistance and voltage according to the value(s) in the table below.FRONT LIGHT ECU (FRONT CONTROLLER)
Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition A52-1 (BATB) - A50-2 (E) P-W-B Power source Always 11 to 14 V A52-5 (ALTB) - A50-2 (E) L-W-B Power source Always 11 to 14 V A50-1 (FMB3) - A50-2 (E) LG - W-B Power source Always 11 to 14 V A50-2 (E) - Body ground W-B - Body ground Ground Always Below 1 Ω A51-12 (RDEF) - A50-2 (E) W-W-B Defogger relay Engine switch on (IG) Rear defogger switch ON Below 1 V Engine switch on (IG) Rear defogger switch OFF 11 to 14 V A50-5 (FMIG) - A50-2 (E) Y- W-B Power source Engine switch on (IG) 11 to 14 V Engine switch off Below 1 V If the result is not as specified, the front light ECU (front controller) or fuse may have a malfunction.
- Measure the resistance and voltage according to the value(s) in the table below.
- CHECK AIR CONDITIONING AMPLIFIER
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Disconnect the L76 and L77 air conditioning amplifier connectors.
- Measure the resistance and voltage according to the value(s) in the table below.AIR CONDITIONING AMPLIFIER
Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition L76-5 (IG+) - L76-1 (GND) V-W-B Ignition power supply Engine switch on (IG) 11 to 14 V Engine switch off Below 1 V L76-6 (+B1) - L76-1 (GND) L-W-B Battery power source Always 11 to 14 V L76-7 (+B2) - L76-1 (GND) L-W-B Battery power source Always 11 to 14 V L76-1 (GND) - Body ground W-B - Body ground Ground Always Below 1 Ω L76-2 (FGND) - Body ground W-B - Body ground Ground Always Below 1 Ω L77-6 (RGND) - 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.
- CHECK MULTI-DISPLAY
- Disconnect the L59 multi-display connector.
- Measure the resistance and voltage according to the value(s) in the table below.MULTI-DISPLAY
Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition L59-1 (+B1)-L59-10 (GND1) R-W-B Battery power source Always 11 to 14 V L59-3(IG)-L59-10 (GND1) V-W-B Ignition power supply Engine switch off Below 1 V Engine switch on (IG) 11 to 14 V L59-10 (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.
- CHECK INTEGRATION CONTROL AND PANEL (w/o Multi-display)
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Disconnect the L35 integration control and panel connector.
- Measure the resistance and voltage according to the value(s) in the table below.INTEGRATION CONTROL AND PANEL (W/O MULTI-DISPLAY)
Terminal No. (Symbols) Wiring Color Terminal Description Condition Specified Condition L35-1 (+B1)-L35-10 (GND1) B-W-B Battery power source Always 11 to 14 V L35-3(IG)-L35-10 (GND1) V-W-B Ignition power supply Engine switch off Below 1 V Engine switch on (IG) 11 to 14 V L35-10 (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.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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