re: More AC Diag mode.

[Phil Rose <pjrose@servtech.com>]

>Date: Mon, 22 Jun 1998 15:02:13 -0400
>From: Peter Sward <Peter.Sward@digital.com>
>Subject: More AC Diag mode.
>
>Thanks Andrew for reposting Steve Buchholz previous posting. Question, I
>get an
>error code
>9 on channel 1 and that's not listed in the post. Anyone has a clue as what it
>means? This is on
>a 91 V8Q.. Second, does anyone has a decoder ring for the int and ext temp
>readings (Channel3-5)?
>
>Thanks
>            /Peter


Peter,
The following is a copy of something I posted last year.
********
To check the status of each sensor, you can read channels 4 (sensor in
plenum) and channel 5 (sensor on cowl) on your climate control fault
diagnostics readout.  Compare the output to the chart in Bentley (D8-240)
to get the temperature. Each reading should correspond (via the table) to a
temp within about 5 degrees F of actual T outside. BTW, the diagnostic
readout values _decrease_ in a nearly linear fashion as the temperature
_increases_. Temperature of 50 degrees F gives a readout of 127. The
diagnostic number changes by about -1.4 units for every 1 degree F
increase. To a useful approximation (good to within about 3 degrees between
32 and 100F) you could relate T to the readout, D by the following equation:

 T (deg F) = (198-D)/1.4

But beware that the accuracy is way off when much below 32 F.

HTH

Phil

Phil Rose		Rochester, NY
'89 100
'91 200q		pjrose@servtech.com