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.
Inspection Procedure
- CHECK WIRE HARNESS (MPX MASTER SWITCH - BATTERY POSITIVE AND BODY GROUND)
- Disconnect the M7 connector.
- Measure the voltage and resistance according to the value(s) in MPX MASTER SWITCH - BATTERY POSITIVE AND BODY GROUND (VOLTAGE) and MPX MASTER SWITCH - BATTERY POSITIVE AND BODY GROUND (RESISTANCE) .
Voltage
MPX MASTER SWITCH - BATTERY POSITIVE AND BODY GROUND (VOTAGE)Tester Connection Condition Specified Condition M7-9 (CPUB) - Body ground Always 10 to 14 V M7-10 (BDR) - Body ground Always 10 to 14 V M7-20 (SIG) - Body ground Engine switch on (IG) 10 to 14 V Resistance
MPX MASTER SWITCH - BATTERY POSITIVE AND BODY GROUND (RESISTANCE)Tester Connection Condition Specified Condition M7-2 (GND) - Body ground Always Below 1 ohms Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: PROCEED TO NEXT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
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.
Rather have a pro handle this?
A certified mobile mechanic comes to your home or office. They bring the tools, you stay comfortable. No tow truck, no waiting room, no surprises.
No obligation. See pricing before you book.