EEC-IV Questions

[Brian Warburton, c/o Turbo Systems Ltd]

>A couple years ago, I calibrated some operating modes for the Mark
>VIII so it would run without the MAS hookedup. I'm trying to remember
>if we actually called it a limp-home mode or just a failure manage-
>ment mode. Now that I think about it, I wound't really call that a
>full limp home mode. It was more like a limp-without-the-MAS-mode, 
>something we needed in case the MAS broke or someone forgot to 
>hook it up after changing the air filter. What's the s/w?

In Ford-speak the s/w is the strategy.

LOS mode was entered when the EEC-iv software ceased to run. It is
(or was) controlled entirely by hardware in the EEC-iv module,
effectively the EEC became a hardware only ECU with no processor.
LOS used to give a fixed fuel p/w (used to be around 3mSecs) fixed
spark (used to be 10 deg BTDC) fixed ISC dutycycle (used to be
around 50%) and so on, the values varied from engine to engine. I
seem to remember some later modules had "programmable" LOS values
instead of hard-wired in values. What I think you're talking about
Ed is the FMEM system in the strategy which attempts to keep the
engine running under software control when sensors and/or actuators
fail. i.e. when MAF fails, start using TP instead for load, when
ECT fails derive a substitute ECT value from the ACT sensor and
time-since-start and so on ........ 

Mind you, it has been 16 months now, it's all getting a bit hazy.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Brian Warburton,   "Still searching for the perfect curve....."
email: bwarb at turbo.win-uk.net
                               Advanced Automotive Electronics Ltd,
                               Van-Nuys House, Scotlands Drive,
                               Farnham Common, England.  SL2-3ES
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