1977 Cadillac Deville

UPUTAT

MEMBER
1977 CADILLAC DEVILLE
V8
2WD
AUTOMATIC
46,000 MILES

The heater blower motor stopped working in my 1977 cadillac. There is no current going to the motor. If you jump it the motor runs. Must be a common problem. My 86 caddy has same problem.

Saturday, February 6th, 2010 AT 2:25 PM

7 Replies

RASMATAZ

MECHANIC
75,992 POSTS

Could be the blower motor relay or the blower control switch

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Saturday, February 6th, 2010 AT 2:30 PM

ELLIOT ECKSTEIN

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3 POSTS

Where is the relay. Dose the relay run anything else

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Saturday, March 11th, 2017 AT 4:59 AM

HMAC300

MECHANIC
48,601 POSTS

Unfortunately we don't list anything for that model year as far as relays. You might check inline fuse behind alternator and on top of heater box under h ood is usually where it was put back then.

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Saturday, March 11th, 2017 AT 6:31 AM

ELLIOT ECKSTEIN

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3 POSTS

Nope it doesn't have anything there

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Saturday, March 11th, 2017 AT 6:57 AM

HMAC300

MECHANIC
48,601 POSTS

It may not have a relay I forgot it s' been so long. It may be the resistor is burnt up as well which should have a 4/5 way plug and on heater core under hood. I'm not really sure a relay was used then.

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Saturday, March 11th, 2017 AT 7:53 AM

ELLIOT ECKSTEIN

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3 POSTS

This is where I looked

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Saturday, March 11th, 2017 AT 8:08 AM

HMAC300

MECHANIC
48,601 POSTS

The single arrow points to the resistor take that out and see if any part of it is broken that controls all your speeds then where the double arrow is follow that line it may lead to the relay if there is one. However that is auto temp control so there may be something else wrong. Also on the resistor the wiring used to burn off right at the resistor which would not allow blower to work it would do the same at switch in dash.

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