Hey hey,

I have a EF Fairmont i6 Auto, and have had lots of trouble starting it over the last month or so.

I think its to do with bad voltage and the immobiliser (smartlock) keeping the engine from starting.

Normally When it starts up, with the key inserted and in the accessory position (warning and test lights on dash) it will light the dash ODO display and trip computer normally, voltage will be in the middle of the guage (13-14v?) and no sign of the smartlock light. It will turn over and start right up. But leaving it for a bit and coming back to it 10 mins later it was immobolised again and stays that way for hours at a time.

I noticed just tonight when I was in the garage trying to start it up and when the key was in the same accesserories position. The voltage was sitting at about the 1st marking above the red (10v?) with the radiator fans audible under the bonnet, and the ODO display and the Trip computer display remaing dark. Smartlock light will stay dark untill you try and start it, then it will come on and flash while the engine is cranking over.


After about 30 mins (on this occasion) it started up properly, but I was paying attention to what was going on with the electrics and relays under the bonnet and dash to discover that something is making the radiator thermo fans spin and drain the available volts, probably activating the smartlock as a unwelcome side effect.

Has this happened to anyone else before? Would it be ECU, BCM, Fuses, Loom or Relays making this happen? I dont know whether to take it to an sparky or a mechanic, or back to Ford and pay the premium service fees.

Where do I start?

Last edited by Jordan on Thu Jan 25, 2007 9:53 am, edited 1 time in total.

How old is the battery? If you have a multimeter use it to check battery voltage.

Battery is ok actually. When I attach a fully charged jump-start/booster pack it makes no difference at all.

I have found that if I quickly switch the ignition from ACC then back to ON (not cranking it) a few times in a row (8-10 times) I can watch and wait for the trip and dash lights to come back on, there will be a loud click like from a relay from up front of the enginebay, fan will turn off and I can then start up and go.

Although 50% of the time it will sometimes stop dead mid-crank when its just started to kick over which dosent feel good at all for the starter motor. The other 50% it just start right up like normal. This is so annoying.

Sounds like an earthing problem somewhere.

Well bugger me !!!!!

Somebody else has the same fault as my car, at least from your description it sounds exactly the same as mine..

I've spent many hours trying to find my fault but with my car it will do it 4 or 5 times randomly over a week and then not do it again for months. The other problem was every time I started to pull panels off to start checking signals the bloody thing would stop doing it .

What I did find was that for some reason power wasn't getting to the ECU (I replaced relays and checked wiring but to no avail) so I went around the problem by putting a switch under the dash that runs from the Ign Power cable to the ECU's V+.
So now if the ODO and climate don't light up when I turn on the Ign, I give the switch a flick and everything powers up. The only thing is you have to remember to flick the switch off with the ign otherwise the car stays idling .
The problems still not fixed but at least when I need to be somewhere and it decides NOW is the time to start playing up, I can just flick the switch and drive off....
Good luck and lets us know if you find it and get it fixed.

Tell me about it, I have broken down 3 times in the last 2 weeks in rush-hour on Parramatta road, and the City Westlink. Will block an entire lane as it happens at walking speed and I dont have enough momentum to get out of the main flow of traffic (which is bumper to bumper). Very embarrasing.

I will give that switch thing a go, it sounds like a good workaround. Will be taking it back to Ford in a few months for a major checkup.

Regarding this, if the ECU is not getting 12v, that means there is a short somewhere in the wires between the ECU and the ACC circuit from the fusebox? Do you have the problem with the radiator fans switching on also? I'm thinking my fans are both the symptom as well as the cause, as when I'm idling in traffic it gets hot, and the electric fans want to kick in and shorts, taking +'ve voltage from the ECU.

When I'm in the garage at home and the engine is cold, the fans coming on must mean that the same short is acting up again and still taking +'ve away from the ECU.

Where can I get a copy of the wiring loom? I want to know what wires I need to trace, and where they run behind the dash.

Well I'll describe my problem a little better..

Now I don't know if my thermos come on when this happens cause in the Fairlane I never hear 'em running at any time.
Luckily mine hasn't just totally cut out while driving only a short break in acceleration, most of the time randomly when I go to start her.
I get the same symptoms as you with the dash, My ODO lights up just barely along with the trip and clock and when it comes good I hear a relay clicking in around the BEM area.
OK so I replaced the BEM and it was fine for a couple of months before it did it again (this was before I knew the EEC wasn't powering up).
I then thought maybe bad earthing somewhere, so redid the battery leads and terminals and even put a fresh battery in, again it was OK for a while before it came back with a vengance.
I'd had enough and thought take it down to Ford (maybe they've seen this thing before) they replaced the IGN switch / Smartlock module although it didn't do it while it was with them. So it was OK again for a few months then it happened again. When it did it this time tho I had a Megasquirt and Wideband O2 unit hooked up to the power supply going to the stock EEC and they both went dead.
Ah HA I though must be EEC relay under coolant tank (Stupid F*^&en place to put electrics, but anyway) replaced every relay under there.
As you might guess, Fine for a while then at it again.

That's when I spat it and put the bypass switch in..

As you can see I've put a bit of thought in this and I've become very well aquainted with the Ford factory manual (all 3 volumes) and being an electronics tech my best guess at the moment is a signal coming or going from the BEM thats not switching correctly. Maybe a wire thats giving a varying resistance...
Also the damn thing won't stay faulty long enough for me to track it fully plus I'd have a better chance if the manual included a circuit diagram of the BEM, but theres only the pin in and outs detailed.
So there ya go.. For me it doesn't matter anymore cause if you've checked the link in my sig, you'll see there's not much that'll be stock under the bonnet after I've finished..
I guess if you want the sections of the manual that relate to all this then I can scan 'em off but you'll have to pm me you car details, an email address I can send a s**t load of data to and give me a few days to scan the bits I might not have scanned already..

Problem solved, thanks everyone for your feedback

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