How to do an ECU reset
 

Does anyone know how to do an ECU reset? I've just done a search on the subject and come up with about 6 different permutations of disconnecting the battery and pressing the brake pedal.

I guess I am the first to try one then. Here's what I did and my experience. Any comments/additions welcome.


ECU Reset:

1. Disconnect the negative terminal on the Battery.

2. Pump the brakes about 20 times to remove any residual charge from the system. (From where or what I don't know).

3. Reconnect the battery.


Results:

1. When the car is restarted, the DCS OFF light flashes and stays that way until you have driven the car around for a while. For me it went away after roughly 10 minutes and 10km of driving. This is normal. When the light stopped flashing, the 'car with squiggly lines' symbol came on. After a quick stop-go penalty I was back to normal.

2. Doing and ECU reset will reset you trip meters (but not the odometer) and your stereo presets. Other than that it's a painless procedure.

Wildcard

You should be scolded like a bad dog
BAD RX-8 OWNER! BAD!

There is a specific procedure for dealing with recalibrating your steering position sensor after disconnecting the battery.
It is in your owner's manual which you should have read cover to cover!

You are probably driving around with a highly confused TCS/DSC system.

Pull the battery again and then follow the instructions.

Question: Why do you want to deliberately reset it?

Probably to clear a CEL/MIL indicator.

It is also fun to drive a Mazda right after an ECU/PCM reset. Throttle response is more crisp and the torque band is shifted down the RPM band a bit. Makes the vehicle feel a bit faster for a little while until it relearns the TPS calibration and relative knock indexing.

^^ what he said. Plus, I did it because I was experimenting with my Rotary Extreme Intake and wanted to give the ECU a fresh start.

Cheers Maniac for that extra bit of important info. Haven't read the owners manual for a while, but I must say after re-reading it today that it was about the only piece of useful information in there!

Like I said at the beginning of this thread, there are a lot of snippets of information out there about doing an ECU reset, but the complete picture isn't out there for all to read. For example, one of the posts I read talked about driving with the flashing DSC light, so I was expecting it and didn't realise at the time that it wasn't the right thing to do. So here's the updated procedure:

1. Disconnect battery at the negative terminal.
2. Pump the brakes about 20 times to remove residual charge from the system.
3. Reconnect battery.
4. Reset the DSC with the following procedure:
a. Turn the ignition to ON,
b. Turn the steering wheel fully clockwise, then fully counterclockwise and return to centre.
c. Turn the ignition OFF.
d. Turn the ignition back to ON and confirn the DSC OFF and TCS lights go out.
5. Reset your stereo presets and the clock.

If anyone has any more gems of wisdom, please add them and I will update this list. Also, if anyone has more info on how many times to pump the brakes, and what exactly it is doing, that would be helpful.

Cheers,
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