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Can you tell me .....
big_wasa - 20/8/10 at 11:06 PM

Can anyone tell me why the ecu in a manual Ford Mondeo not fitted with cruise contol needs to know the position of the clutch ie up or down ???

PSpirine - 20/8/10 at 11:11 PM

Might not start unless clutch is pressed (I know new cars with button starts need clutch down to crank)?

MikeR - 20/8/10 at 11:12 PM

at a guess ...

so it can figure out to cut the fuel on overrun / go into minimal fuel to keep the engine ticking over / the developers couldn't be bothered having two versions of the ECU.

big_wasa - 20/8/10 at 11:18 PM

quote:
Originally posted by MikeR
at a guess ...

so it can figure out to cut the fuel on overrun / go into minimal fuel to keep the engine ticking over / the developers couldn't be bothered having two versions of the ECU.



I had thougth of that but I think it does that by sensing speed against throttle position ?

big_wasa - 20/8/10 at 11:20 PM

quote:
Originally posted by PSpirine
Might not start unless clutch is pressed (I know new cars with button starts need clutch down to crank)?


Nope it will start with or with out the signal (switch operated)

Madinventions - 21/8/10 at 01:02 AM

From memory, the clutch position is sent to the ECU so it can do all sorts of wierd and wonderful things like impose a lower rev limit (in case you miss a gear), and raise the idle speed to prepare to pull away - that sort of thing. I don't think it does anything too spectacular, but the eec-v is a clever bit of kit and who really knows what goes on inside it?

Ed.

redscamp - 21/8/10 at 03:12 AM

I have a mk2 mondeo 2.0 with "owls" ecu
as far as i can tell the clutch switch does nothing.
i have driven the car with clutch switch shorted and open and cant notice any diffrence.
the presure switch for the power steering makes a very small diffrence to the tickover
(shorted for slower)
the aircon pressure switch does not seem to effect the tickover as far as i can tell.
there is a spur from the vehicle speed sensor/speedo wire going to the ecu,
I have not played with this yet.
I think clutch switch is wired to the ecu as standard regardless of ecu type or market (uk/usa) and the signal is needed or not.

big_wasa - 21/8/10 at 10:38 AM

Ok a couple "more" hours on the web latter.

It would look like that it does have some kind of limit set at around 4k and that it retards the ignition a touch to make a smoother gear change.

On the the eec-iv and early v it wont give a dtc code but it it will on newer models.

So I can bin that function.

One of the functions of the ac presure switch is to so the ecu can turn the fan on at a slow speed. si it has air flow when at a standstill.

No Ac so I can bin that aswell.

I am working on a 1999 owl5, I am already running the 1997 owls in the 7.

I am trying to find all its connected functions. I am nearly finished. I just need to finish the charge system.

StrikerChris - 21/8/10 at 01:20 PM

You want to try working out a 200sx ecu!door switches,boot,speedo,air temp,abs,aircon,brake lights,reverse light,fuel gauge,brake bias valve,on and on and on,all ended up at the ecu!and only the speedo made it as far as the striker!

big_wasa - 21/8/10 at 03:58 PM

No problem if I had it in front of me