How to reset and relearn the ECU

02-05-2005, 06:23 PM
There are a lot of differing opinions on how this done. I was fortunate enough to stumble upon a link here somewhere to a Ford Master Mechanic with the correct method, which I used and which worked. I have lost the instructions for relearning but will post the reset procedure. Hopefully someone has the definitive method for relearning the ECU. I know it involves several restarts with and without A/C and lights on at various RPM's.

To Reset ECU
Remove negative battery cable.
Turn on headlamps (to discharge capacitors).
Wait 15 minutes.
Turn off headlamps.
Replace negative battery cable.

02-07-2005, 07:24 PM
According to the Maintenance manual, the ECU will relearn the engine after three episodes of the following: the vehicle slows from 60mph down to 40 (with accelerations) such as would happen coming down an offramp from the highway.

04-23-2008, 11:36 AM
Does such relearning concerns ECU or tranny? What about this method: reset the PCM, start engine without touching acc. and wait till it gets normal operating temp. - this means wait till fans start working at 100C.

05-06-2008, 07:55 PM
There was a very good piece of information shared by one of our friend here on this forum. I believe it was on the "hesitation"
It worked very well for me...
This is what it basically said.....

Dont Forget,, If the battery has been changed, Was the Idle setup correctly?
You can relearn the idle by disconnecting battery for a few mins. Connect battery, and start engine. Let it run until its HOT Idling to 700ish rpm.. Better to do this when engine is already hot.. This way you wait two mins or so.. They say 1 min - NO LESS and in Park!!
Then, Put your Shifter in Rev 10 seconds or so, Then Net, then Drive, then 2, then 1st.. If you have OD and D Just do them ALL!
Then back to park, then Take it for a DRIVE!

Thanks to the person who shared this one.

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