Engine Codes

Engine Codes

If the [=ECU=] (Electronic Control Unit) detects a problem, the orange “Check Engine” light comes on. This in itself isn’t very helpful. However, it’s pretty simple to get the orange “Check Engine” light to provide a little more information as to what might be wrong.

  1. Open the service connector (a little black box, about 1" square, at the very back of the can near air intake). Short the terminals marked T and E1 with a wire. /MK1/diagnosis-box.jpg

  2. Turn all accesories off, especially A/C. Put the ignition key in ON position. The orange “Check Engine” light on the dash should flash. The lights will flash with 2.5 seconds between each error code, and with a 4.5 second gap before repeating.

!Number of Blinks !Meaning
1 Normal – no problem
2 Air Flow Meter
3 Ignition
4 Water Temp Sensor
5 [[Oxygen Sensor]]
6 RPM
7 Throttle Position Sensor
8 Intake Air Temp Sensor
10 Starter
11 Switch signal (A/C switch ON)

Thus the sequence below would translate to an Ignition problem and a problem with the Oxygen Sensor.

->3 flashes -- 2.5 second gap -- 5 flashes -- 4.5 second gap -- 3 flashes -- 2.5 second gap -- 5 flashes ...

Clear the ECU Memory

Once you’ve identified and fixed the problem you need to clear the ECU memory, otherwise when you next get a problem, you’ll see the old problem, followed by the new code.

Either:

  1. Remove the 7.5A `AM2 fuse in the main fusebox near the battery.

  2. Disconnect the battery for around 10 seconds. Obviously this is going to reset your clock, radio settings, etc.