I have a 90 Cadillac 4.5 (actually mom's) and the air conditioning fan stayed on after the car was shut down and the letter " d " or a backwad "6" appeared in the screen on the climate control and on the gas mileage/fuel economy readout. Both the climate control and the fuel economy read out are NON resonsive with this letter " d " in both LED readouts.

With wisdom from this site I changed out the blower control module from a spare Cad that I have and although the fan does not run anymore after the key is out I still have non resonsive readouts on both the other units.

When I put the key in and turn it on the fan comes on full blast and there is no way to control it because the climate control panel just displays the "d" and nothing more will it do!!!! arrrrrgh

anything else I can do b4 I take it to the Grim$$$$ Reaper, my local Cadillac agency

thanks

Joe

Hey, there is a diagnosis chart in the alldata for the 90, email me and I can send it to you.

I tried to post a message to you but I'm a "new kid" and it would not let me post to you directly.......... Im at whosale@pacbell.net would be VERY apreciative of that cad info on my car

Thanks in advance

Joe

In the mail now, hope it helps!

A 'd' in the CCP and FDC indicates a bad PROM chip in the Body Control Module, or more likely a bad BCM. Go to the junkyard, pull a BCM and plug it in. Betcha that fixes it.

VERRRRRY NICE INFO........ iM OFF TO SCAVANGE MY DEAD 89 FLEETWOOD COUPE FOR ONE LAST PART B4 IT GOES TO THE BONE YARD

THANKS VERRRRY MUCH

jOE