Automotive - Properly RESET Car Computer

Given W=V^2/R, your 1Ω resistor will be dissipating over 160W if you put it across 12.8V. You'd need something like a 200W resistor, not 10W

Just click on the headlights or sit on the brake pedal, disconnect the battery, problem solved, no need for a circuit

Battery terminals are dis connected first and not across full battery load. No need to fully run down a battery leaving the headlights on when 10 or 15 minutes through 1 ohm resistor. My 10 watt 1 ohm resistors from Amazon came they test 1.5 or 1.6 ohm on my ohm meter.

That's what I said lol, disconnect the battery, and press the brake or turn on the headlights, that's your resistor, it's built into the vehicle, saves you having to buy/make a tool 😉

Modern cars have numerous computers. How do you know brakelight circuit clears all computers?

Because all computers clear after atleast 15 minutes of no power, capacitora don't tend to hold charge past that point without a load, let alone with one on

So, erasing all set default codes happens in fifteen minutes of no power?

Roughly, yeah

@ETJAKEOC, with all the different car computers, wiring, relays to lights, and computer request circuits if computer thinks okay to turn something on.... exceptions will exist for most any rule. Completing battery terminal circuit without voltage spike seems needed to discharge a system well. The 1.5 ohm level could be lower than taillight or headlight voltages would flow. If LED lamps with resistors I do not know resistance when current discharge would stop? Defective computer still might not clear properly. Jumper wires connections between battery terminals and 1.0 ohm level resistor seems practical and if more than one car to be reset - a time saver.

Well, if you really want to save time, just disconnect the positive wire from the battery and short it to ground lol, nothing saves time like sparks flying 😂

Voltage spike damage may cause more time and money. So far, I have never had to do a full reset. If codes never cleared after repairs, it might be necessary.