General How To Reset My ECU?

Currently reading:
General How To Reset My ECU?

disconect the battery for an hour

As above, but then you need the RED Master key. Without the RED Master key you can not as far as I am aware reset the ECU.

I have included the following from BOO website http://www.bravo-guide.co.uk/fix-a-bravo.htm

Resetting The ECU

THIS WILL NOT RESET THE AIR BAG WARNING LIGHT

This is the basic reset which will restore the various positions back to factory setting.

Disconnect the battery for a minimum of 45 minutes. Simply remove the earth side (-) and pull to one side.

When you reconnect the battery and start the car for the first time do NOT rev then engine for 5 minutes. This allows all the postioning motors to go back to default. Once the 5 minutes is up you may stop and restart the car then drive normally.

All the "reset" does is put the positioners such as the IACV back to factory setting. The car will then relearn the positions required for the conditions you put your car under. However if you drive your car hard from the off after doing this, it will expect to be driven like that al the time and therefore may feel a little sluggish unless really pushed. Also, whilst this relearning is taking place you may experience higher running costs.

You will not have to reprogramme any keys afterwards and your radio should not loose its code either. You will have to alter the time unless its a H2 where if you put it to an FM station it will pick up the time automarically.

Key Code Light On

Battery

If the key code light stays on the 1st thing to check is the battery condition.

Hope this helps

Rik
 
I did say as far as I am aware:D I wasn't 100% certain, I thought I read somewhere that it was needed to do a reset but couldn't remember where I saw it, might of been on one of Jug's posts(y)
 
How come "only disconnect the earth wire" I thought you'd have to disconnect the positive??

Resetting the ecu will make the engine management light go out yes??

Thanks in advance

Rich.
 
as for disconnecting... as electricity works in circle, it doesnt mostly matter where u cut the circle, if it cant make the full circle it cant feed anything....
 
How come "only disconnect the earth wire" I thought you'd have to disconnect the positive??

Resetting the ecu will make the engine management light go out yes??

Thanks in advance

Rich.

it will clear the stored error codes but thats not what you want.

if your injector light is on you have a sensor problem, the light will go out once it has been fixed regardless of an ECU reset.

Ry
 
Red key is NOT needed when resetting ECU. Simply disconnect black (earth) wire from battery and pull it aside for 30min/1hour, then reconnect it and follow istructions rikmargetts posts before, about the first start and the "re-learning process" ;)
 
Hope you dont mind me jumping on this post but I have a brava not bravo and it is running great (at the mo) but my engine managment light is staying on, will resetting my ecu take this light off? and do I follow the same procedure?
 
Hope you dont mind me jumping on this post but I have a brava not bravo and it is running great (at the mo) but my engine managment light is staying on, will resetting my ecu take this light off? and do I follow the same procedure?

Nope, engine management light needs to be reset with a diagnostic reader.
 
Nope, engine management light needs to be reset with a diagnostic reader.

...and usually this light means something is going wrong in the engine... maybe is not important, maybe is something that will become important if not checked in time... so the best thing to do is a diagnosis to investigate the problem.
 
on the mk2 hgt, remove both the positive and negative leads of the battery and connect them together "bridge" (clearly while not on the battery) then count to 30.

This will clear any issues with stored error codes. On some of the errors it will simply turn off the injector light when resolved, others it will keep the injector light on till a specific number of ignition cycles have completed with out the error occurring again.

with the hgt mk2 (the mk1 runs a very different ecu) because its uses a fly by wire system. once started for the first time after a ecu reset, let it sit on tick over for 5 minuets till it drops to its 600-700 rpm. Then over the next 100 miles, drive it as you would normally drive it. The tps is adaptive over them 100 miles and "learns" how you like to drive, moving the throttle response up or down the peddle.

If its the mk1, the same process, let it tick over for 5, but as its a cable TB you don't have to worry about the adaptive aspect

As far as the red key is involved. Its always a possability, but its about as likly as you going out to start it now and it suddnly demanding a red key.

mabee its worth while getting one sorted out...while you dont need it?
 
Last edited:
Back
Top