|Getting the ECU codes from the Mk1
Description A "How To" guide to accessing the onboard diagnostics on the Mk1. Codes and images are included
Author ldavies83 Date Thu Aug 04, 2005 9:19 pm Type Picture How-To
Viewer Comments [4 - Post your comments]
|The Check Engine Warning Light
The Warning light is located on the dashboard (image below) . When the ignition is switched on, the light should illuminate, as soon as the car is started however, the light should extinguish.
The Check Engine Light
If the light remains on, then the ECU has detected a fault that will need to be seen to.
In order to obtain the error codes, the following conditions have to be true
· Ensure you have a minimum of 11 Volts at the Battery
· TPS fully closed (Throttle Position Sensor)
· Car is in neutral if you have an automatic box
· All electrical items are switched off
· Engine is at normal running temperature
Switch the ignition on (Key position 2), but don’t start the engine.
Grab a paper clip or similar short piece of wire; Insulated is best, as you don’t want to short it against any bodywork. I prefer those coloured paperclips!
Now the diagnostics connector is bolted to the chassis, to the left next to a “Resonator Box” (4A-GE illustration below) - thankfully its rather aptly labelled “Diagnostics”! The location of the plug on 4A-GZE (supercharged) engines is near the intercooler.
Lift of the cap and you will probably be greeted with a load of gunky grease. This is correct! This is to stop water ingress.
Connect one end to Terminal T, and the other to E1. See the picture below to work out which is which. But there is also a diagram on the inside of the cap.
Output of Diagnostic Codes
The codes are outputted using a sort of “Morse Code” system, pulsing the “Check Engine” Light x number of times, then pausing, then moving to the next Code. The pause between codes 10 and over is represented by a 1.5 second pause. The pause between the codes is 2.5 seconds, and then a final 4.5second pause tells you its reached the end of the code. The ECU will then start the flashing process from the beginning again
Lets take an example:
Error Code 6 and 12 would be translated as
Resetting the diagnostics
Obviously remove the quote “service wire” unquote (read: paperclip) firstly
You can now reset the system one of 2 ways:
Disconnect the battery (but you will loose stereo settings, clock, alarm, etc)
Remove fuse AM2 in the fusebox behind the battery for at least 10 seconds
After you’ve done that the codes have been removed, drive the car, and check again to make sure the car reads Code 1 ie normal.
That’s about it! The document below is the actual codes and what they mean.
Thanks for reading!
Click here to download the ECU Codes in PDF Format