[Gmecm] Ignition off fan

[Robin Handley]

Thanks Scott, although I'm confused. The $58 code has lookup values for two
fans, so I had assumed that the Sunbird and/or Sy/Ty had two fans. Am I
wrong? Since I have proved that the high fan temperatures drive my fan, it
would be weird if the low fan temperatures weren't used for something...
What am I missing?

Robin

----- Original Message -----
From: "Scott Peitzsch" <jlg-sep at comcast.net>
To: <gmecm at diy-efi.org>
Sent: 28 June 2006 01:09
Subject: Re: [Gmecm] Ignition off fan


> Sadly, no.  The '749 ECM lacks quad driver U20, which would normally
> have driven the Secondary Cooling Fan output at pin F8.  Its sister ECMs
> (the '727 and '730) have this driver and the capability to run both fans.
>
> Since you're reworking code anyhow, or at least on your way, you might
> consider redirecting the secondary fan output to another existing quad
> driver
> channel whose original function can be eliminated in your application.
>
> -Scott
>
> ----- Original Message -----
> From: "Robin Handley" <Robin at FuryWorld.fsnet.co.uk>
> To: <gmecm at diy-efi.org>
> Sent: Tuesday, June 27, 2006 6:34 PM
> Subject: Re: [Gmecm] Ignition off fan
>
>
> > Thanks Scott. Both fans?
> >
> > Robin
> >
> > ----- Original Message -----
> > From: "Scott Peitzsch" <jlg-sep at comcast.net>
> > To: <gmecm at diy-efi.org>
> > Sent: 27 June 2006 23:26
> > Subject: Re: [Gmecm] Ignition off fan
> >
> >
> >> > Anybody know if the Sunbird/$58 code supposed to keep the fan running
> > when
> >> > you turn the ignition off? There seem to be calibration timing values
> >> > which
> >> > suggest it... but mine goes off (mind you, it is wired as the hot
fan,
> > and
> >> > that may be different. Trying to work my way through the fan code...
> >>
> >> Yes, there is code which will allow the fans to run-on after
ignition-off
> > if
> >> the
> >> coolant temp is above a threshold.  This feature is especially useful
on
> > the
> >> turbo Sunbird when its been shut off immediately after a hard run on a
> >> hot
> >> day.
> >>
> >> -Scott