1980 corvette location of power door lock relay and chassie grounds

A electrical short circuit keeps blowing the fuse . Looking at a wiring diagram an using a DVOM - digital volt ohmmeter to test the electrical circuits is how to find the problem . With not having the vehicle here to test i would only be guessing as to what the problem is . Plus you need to train to learn how to fix these type problems .
https://www.youtube.com/watch?v=SO-eKuhCOqc

https://www.youtube.com/watch?v=efKoWifdcag&t=4669s

You need to look an see what else that fuse powers ,fuse's sometimes power other thing's besides what the fuse is called .Power locks fuse # 32 20 amp. Does the car have keyless entry ?
xTooltipElement
Service Information
1999 Chevrolet Monte Carlo ' Monte Carlo, Lumina (VIN W) Service Manual ' Body and Accessories ' Doors ' Description and Operation ' Document ID: 292071
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Power Door Locks Circuit Description
Models Without Keyless Entry
When either door lock switch is pressed in the power door locks system, all doors lock or unlock in unison. Each lock can also be operated manually from the locking knob.
The locks are operated by reversible actuators that receive voltage from the door lock relay assembly's two built-in relays. The relays energize the actuators by applying voltage to one of the terminals and ground to the other terminal. In order to reverse the actuators, the polarity to the terminals is reversed.
The door lock switches are usually closed briefly. If the door lock switches are held closed, a circuit breaker in each actuator will open to protect against damage. The circuit breaker resets only after voltage is removed from the actuator.
Lock Operation
Pressing the lock position on either door lock switch sends a voltage signal in CKT 195.
Pressing the lock position turns on the lock relay located inside the door lock relay assembly. The lock relay completes the circuit that supplies voltage to CKT 295. CKT 295 is the voltage feed to the actuators.
At this time, the unlock relay is not energized. When the unlock relay is off, CKT 294 is grounded, which provides a ground path to the door lock actuators.
The entire action described completes the electrical circuit the actuators in each door, thus locking the doors.
When the door lock switch is released, the lock relay contact closes to ground, and the actuators turn off.
Unlock Operation
Pressing the unlock position on either door lock switch sends a voltage signal in CKT 194.
Pressing the unlock position turns on the unlock relay located inside the door lock relay assembly. The unlock relay completes the circuit that supplies voltage to CKT 294. CKT 294 is the voltage feed to the actuators.
At this time, the lock relay is not energized. When the lock relay is off, CKT 295 is grounded, which provides a ground path to the door lock actuator.
The entire action described completes the electrical circuit to the actuators in each door, thus unlocking the doors. The polarity of the voltage to the actuators has reversed, causing the actuators to run in the opposite direction in order to unlock the doors.
Models Equipped With Keyless Entry
All door locks operate the same as vehicle models equipped without keyless entry, except the left front door lock.
Lock Operation
Pressing the lock position on either door lock switch sends a voltage signal in CKT 195.
Pressing the lock position turns on the lock relay located inside the door lock relay assembly. The lock relay completes the circuit that supplies voltage to CKT 295. CKT 295 is the voltage feed to the actuators.
At this time, the lock relay is not energized. When the lock relay is off, CKT 295 is grounded, which provides a ground path to all door lock actuators, except left front door lock actuator.
The left front door actuator is grounded through the Remote Control Door Lock Receiver, RCDLR, CKT 694. The RCDLR has a built-in relay. When the built-in relay is de-energized, the relay provides a path to ground to the left front door actuator.
The entire action described completes the electrical circuit to the actuators in each door, thus locking the doors.
When the door lock switch is released, the lock relay contact closes to ground, and the actuators turn off.
Unlock Operation
Pressing the unlock position on either door lock switch sends a voltage signal in CKT 194. The signal is sent to both the unlock relay located inside the door lock relay and the Remote Control Door Lock Receiver, RCDLR.
Pressing the unlock position turns on the unlock relay, and signals the RCDLR to unlock the left front door. the unlock relay completes the circuit that supplies voltage to CKT 294. CKT 294 is the voltage feed to the actuators, except the left front door lock actuator.
The left front door actuator receives voltage through the Remote Control Door Lock Receiver, RCDLR, CKT 694. the RCDLR has a built-in relay. When the built-in relay is energized, the relay provides a voltage to the left front door actuator. The RCDLR energizes the relay when it receives a voltage in CKT 194.
At this time, the lock relay is not energized. When the lock relay is off, CKT 295 is grounded, which provides a ground path to all door lock actuators.
The left front door actuator is grounded through the Remote Control Door Lock Receiver, RCDLR, CKT 694. The RCDLR has a built-in relay. When the built-in relay is de-energized, the relay provides a path to ground the left front door actuator.
The entire action described completes the electrical circuit to the actuators in each door, thus locking the doors.
When the door lock switch is released, the unlock relay contact closes to ground, the RCDLR left door unlock control relay contacts close to ground, and the actuators turn off.

You can find free wiring diagrams here
http://www.bbbind.com/tsb-wiring-diagrams-database/

Locate and replace the fuel pump relay and see if it will start then. Also, make sure that the battery terminals are clean and secure; also on the starter, and the ground (at chassi - or block, wherever the ground leads).

Please let me know if you need further assistance.

carsandcomps,

Guru, Premium Expert @ Fixya.com

It should be plugged into the fuse panel on the firewall. Here is what it looks like.

http://www.ecklers.com/product.asp?pf_id=20494&dept_id=1723

check for power at the horn, the relay sends the ground

I had the same problem on my 80 vette several months ago. The blower relay is located on the firewall top side (engine compartment,passenger side). It is a silver rectangle about 2"x1"x1" . Pull out the wiring plug and check to make sure it hasn't melted due to a loose connection. NAPA sells a new plug that can be spliced into the wiring harness. Let me know if you have any questions.

Mark

Fuses are located in the junction box below the instrument panel to the left of the steering column. The turn signal flasher and hazard warning flasher also plug into the fuse block. Each fuse receptacle is marked as to the circuit it protects and the correct amperage of the fuse. In line fuses are also used. Refer to the Fuse Chart at the end of the information for their location. The fuse block on some models is a swing-down unit located in the underside of the instrument panel adjacent to the steering column. Access to the fuse block on some models is gained through the glove box opening. The Convenience Center on some models is a swing-down unit located on the underside of the instrument panel. The swing-down feature provides central location and easy access to buzzers, relays and flasher units. All units are serviced by plug-in replacement. Location of Convenience Center on specific models may vary.

check the wiring between the door and body it may have gotten brittle and cracked or broken this would explain the intermitten lock function

Here is a wiring diagram for the 1980 Corvette power door locks.

Link to: diagram

Hope this helps.

The power steering pump on a 1980 corvette is located directly under the alternator. I have found it easiest to reach between the alternator belt and unscrew the cap, then use a long stemmed funnel to fill it. If you shine a flashlight down into the spout, you'l avopid overfilling.