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To be more specific its a 91 eldorado. i have the wiring grid for the bcm but can't locate a relay. everything i read suggested control module/resistor but nothing changed with a new one.

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Please , do post all facts. none of this makes any sense
sorry !
what car, 91 eldo, ok. Caddy. a very old car. (problems aplenty)
what engine?????????? is it an engine issue???????
3.0, 4.5,4.6l or 4.9Liter ? DOHC engine>?

what country> (guess USA, but how would i know that?)
BCM a 91 has a BCM. ill look that up, GRid what is a grid.?
why not post the symptoms and get GREAT advice.?
I see no BCM, (body computer in 1991 only the PCM /ECU)

ok i now read all you post and see the word blower.
the HVAC blower?
some cads have, quote.
A vehicle that has front and rear climate controls may be configured differently than a vehicle that has front controls only.

does the blower fail on all speeds,?
ok, you said, blower runs with the ignition key removed.
this is NOT a blower problem, its a KEY issue.(circuiT)
AH, GRID, you mean a SCHEMTIC, or wiring diagram.
the FSM has this as does (should)

sadly my online source the climate control module is not covered.

Id check my ignition key (off) the pins on the switch proper
do not have power on the output pins.
this car has yellow wire that is hot at all times
but the others must be dead key off.
other key facts. no pun

under dash "intererior relay center"
pull the relays 1 by one ,see if the blower goes off, be a big clue.

15 relays there, and 2 spare spots
RAP relay?
RAP Accessories?
Retained Accessory Power
some cars have this , and delays the aCCessories from turning off
until, doors open or even a delay.
what controls this in 1991 ive not a clue.
quotes from web:
The 85 redesign introduced the "retained power accessory" feature where certain features like the radio and power windows remain available for a short period of time after the ignition is shut off.

on new cars this is a BCM function, pure software. too.
cept a relay.
its only my guess that this is RAP failure causing Climate control to fail. pure guess.
no drawings,
id buy the FSM. i never restore any old car without one.
saves me a bundle over time.

like here

and here

Posted on Jun 17, 2014


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Posted on Jan 02, 2017

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SOURCE: Location of BCM

some chatrooms say its in the right side kick panel under the fuse box, I never looked for it myself, hope you find it

Posted on Feb 08, 2009

  • 74 Answers

SOURCE: Body Control Module

Below the instrument panel on the left side henge pillar,or up high behind the Instrument panel depending the model and options!


Posted on Mar 09, 2010

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