Just brought an EF and on day one I could turn on the Econ switch and it was working fine. That night I tried out the diagnistics mode on the instrument cluster just to have a sticky beak. Next morning I find Econ is not working.

Did I do something to disable it?
Is this purely coincidence, and I have another problem?
What might I look for to rectify this problem?

Thanks
Tony Steward
1995 EF Falcon Sedan Auto

First thing i'd being doing is checking that the cable is plugged into the switch.

Pop out your gear shifter surround and at the back of the economy button there should be a cable that goes in to the bottom of the clip - check that first

as ofyagutts said.

but the common thing as well is that it seems plugged in but you plugged it wrongly, the pins not goin into the plug but past it. have a good look when u plug it in ull see what i mean

or your switch is dead?

I checked switch with multimetre and it is ok. When the misses comes back I will triple check the plug to ensure proper contact.

Second thing i'd check is that the bulb hasn't blown.

Ok it is definantly not the switch, I checked & tested it. I also tried dirctly shorting the two wires together and still nothing on the display.

I haven't checked the globe yet but you can tell by the way the car drives that it is not changing to economy mode.

For EF's:
ECU pin 29 (grey/black) is connected to the economy switch.
ECU pin 79 (orange/white) is connected to economy indicator lamp in cluster.
The other side of the conomy switch (red wire) goes to earth.

To test, ground ECU pin 29 and the economy lamp should light up.

If it does light up, then your problem is somewhere along the wiring between ECU and the economy switch, the economy switch itself and the wiring on other side of the economy switch to earth

If it does not light up, the problem could be within the ecu or along the wiring to the cluster (economy lamp) or the economy lamp itself.

Unfortunately i can't remember if grounding or if applying +12v to ecu pin 79 is needed to light up the economy lamp . To test, i would remove the pin from the connector before grounding (and if that doesn't work then applying +12V) to test the economy lamp (this shouldn't damage the cluster - but it's at your own risk). If doing this does light up the economy lamp, then your problem is within the ECU otherwise it's the lamp within the cluster

Cheers.