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.
1994 Lexus ES 300FACTORY OEM SERVICE PROCEDURE
Code 41 (IG Power Source Circuit)
NOTE:
Ignition keyed power is supplied to ABS ECU through Black/Red wire (terminal A12). Code 41 sets if voltage level in this circuit exceeds 17 volts or goes below 9.5 volts for more than 10 seconds.
- Ensure charging system is working properly. Turn ignition on. Leave ABS ECU connectors attached. Measure voltage between terminals A2 and A12 of ABS ECU connector. See Figure. If battery voltage is present, replace ABS ECU. If battery voltage is not present, turn ignition off.
- Check resistance between chassis ground and terminal A2. If resistance is more than one ohm, repair circuit between ABS ECU and ground. If resistance is one ohm or less, check ECU-IG fuse. If fuse is blown, repair short to ground. If fuse is okay, check circuit between battery and ABS ECU.
Factory Service Tools
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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.