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Discussion Starter · #1 ·
Under the driver's side dash, behind the coin holder, there is a green connector (both male and female) that is just dangling there, unconnected. Does anyone know what it is for before I connect it ? Thanks.

Raj
 

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I think it resets the ECU, its meant to be disconnected.

repeat:

Do Not Connect IT!

:)
 

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Discussion Starter · #3 ·
If it resets the ECU, why does everyone disconnect the battery? This is much easier. I think it is for some other purpose. :confused:
 

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This appears to be the diagnostic connector the dealership would use to reset your ECU:

(Found this with a google search eventually on MRT's website)

ECU clear memory procedure is as follows for auto and manual transmissions:

With engine at operating temperature, turn engine off. Place gear shift lever into park (auto transmission cars only)
Locate the two ECU check connectors, for most cars they are located under the steering column and consist of a black plastic male and female connector, and a green male female connector. The exact location of the connectors varies with the different year models, but generally they are located under the steering column on the drivers side.
NOTE: sometimes they are still taped over with some small amount of plastic tape, so look hard, they will be there!
With the ignition OFF connect black to black and green to green.
Turn on ignition, do not start the engine, (and for auto transmission, cycle the gearshift lever from park to neutral and back to park ), depress the accelerator pedal to full throttle and hold for a few seconds, and then release.
Start engine and then drive for at least one minute, keeping road speed above 11 Km/h.
ECU is now re-set.
At this point the check engine light should start to flash the all clear signal (steady 1/2 second interval flashes). If the check engine light does not flash, or indicates some other sequence, there is a fault present in the system, and should be professionally checked for necessary repairs.
Once, stop the car and turn off the engine.
Disconnect the plugs
 

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wrxraj said:
If it resets the ECU, why does everyone disconnect the battery? This is much easier. I think it is for some other purpose. :confused:
I've often wondered that myself. It seems to me, much easier to do it this way, and requires way less time to do it (IIRC, you disconnect battery for 20-30 minutes to reset that way).
 

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WRXed said:


I've often wondered that myself. It seems to me, much easier to do it this way, and requires way less time to do it (IIRC, you disconnect battery for 20-30 minutes to reset that way).
you don't have to disconnect for any specific amount of time. it's simply a question of getting all of the data out of the ECU memory. diconnect the battery, hit the brake pedal a few times, reconnect the battery. doesn't take more that 5 minutes.
 

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that green one!! I asked the dealer about it and he didn't know (he was the service manager) but when you do connect it, the CEL will flash - so I disconnected it again and let well alone!

I'm not sure if it does reset the ECU.
 

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when you connect it and drive, i think the car goes into "limp mode" or diagnostic mode. it's so service techs can analyze the ECU storage easitly.

see HERE

dR
 
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