1975 beep while (1/2/3) on Drive.
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1st Gear
Joined: Jan 2021
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1975 beep while (1/2/3) on Drive.
I got this buzz beep sound like when I forgot lights where on and turn the car off, coming from the dashboard. But it's only when the car is on and I have it in any Drive position (1/2/3), I've tried different things but can't figure out what it is. Any ideas?
Just another Corvette guy
Joined: Feb 1999
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From: Palm Springs, CA.
Ernesto,
If it only happens when your forward gears are engaged, it sounds like your seatbelt warning system is acting up.
To confirm, try starting the car, put it in drive and then lift the e-brake handle to see if the noise stops.
Follow this info to disable the system:
On manual transmission-equipped cars, the circuit is wired through the ignition switch, the parking brake warning light switch, and a relay, which is located between the instrument cluster wiring and the switch on the parking brake. A diode is used to prevent feedback into the parking brake warning circuit.
On cars having automatic transmissions, the seat belt warning circuit is wired trough the ignition switch and the combination back-up lamp/neutral safety switch.
With the ignition key in the RUN position, a weight of 40-50 lbs. on the driver's or passenger's seat pressure-sensitive switch) energizes the circuit when the parking brake is released (M/T) or the gear selector placed in a forward drive range (A/T).
A warning light will glow and a buzzer will sound with the circuit energized, unless the seat belts are withdrawn from the retractors and fastened over the laps of the two outboard front seat occupants.
If it only happens when your forward gears are engaged, it sounds like your seatbelt warning system is acting up.
To confirm, try starting the car, put it in drive and then lift the e-brake handle to see if the noise stops.
Follow this info to disable the system:
GENERAL INFORMATION 1972-73 Vehicles
The seat belt warning system consists of lap belt retractor switches, a pressure-sensitive switch underneath the right-hand front passenger's seat, a warning lamp and a buzzer.On manual transmission-equipped cars, the circuit is wired through the ignition switch, the parking brake warning light switch, and a relay, which is located between the instrument cluster wiring and the switch on the parking brake. A diode is used to prevent feedback into the parking brake warning circuit.
On cars having automatic transmissions, the seat belt warning circuit is wired trough the ignition switch and the combination back-up lamp/neutral safety switch.
With the ignition key in the RUN position, a weight of 40-50 lbs. on the driver's or passenger's seat pressure-sensitive switch) energizes the circuit when the parking brake is released (M/T) or the gear selector placed in a forward drive range (A/T).
A warning light will glow and a buzzer will sound with the circuit energized, unless the seat belts are withdrawn from the retractors and fastened over the laps of the two outboard front seat occupants.
DISABLING THE INTERLOCK SYSTEM
Since the requirement for the interlock system was dropped during the 1975 model year, these systems may now be legally disabled. The seat warning light is still required.- Disconnect the battery ground cable.
- Locate the interlock harness connector under the left-side of the instrument panel on or near the fuse block. It has orange, yellow, and green leads.
- Cut and tape the ends of the green wire on the body side of the connector.
- Remove the buzzer from the fuse block or connector.
- Reconnect the battery ground cable.
Last edited by Greg; Jan 20, 2021 at 09:16 PM.
Racer
Joined: Aug 2019
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From: Chicago Burbs
1975 is the first year for the "headlamps on" warning buzzer. It reminds you to turn your headlamps off when you turn your car off. This is normal and it is functioning correctly. The buzzer/relay assembly is located near the fuse panel.
Le Mans Master
Joined: May 2007
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From: North tonawanda NY
If I understrand you correctly, you are turning your car "off" and leaving the headlamps "on". When you do this, you hear a buzzing noise.
1975 is the first year for the "headlamps on" warning buzzer. It reminds you to turn your headlamps off when you turn your car off. This is normal and it is functioning correctly. The buzzer/relay assembly is located near the fuse panel.
1975 is the first year for the "headlamps on" warning buzzer. It reminds you to turn your headlamps off when you turn your car off. This is normal and it is functioning correctly. The buzzer/relay assembly is located near the fuse panel.
I agree its probably the seatbelt buzzer.. I removed my seatbelt sensors on my 74 when I redid my seats. I believe they also prevented the car from starting unless the sensors felt the weight of a person sitting in the seat as well. But I also thought this was a one year 1974 feature the 75 didnt have.
Last edited by augiedoggy; Jan 23, 2021 at 12:52 PM.
Racer
Joined: Aug 2019
Posts: 451
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From: Chicago Burbs
He said the noise is "like" you would normally hear if you left the head lights on... in his case the lights are not on. But the engine is running and the car is in gear... any gear but park position.
I agree its probably the seatbelt buzzer.. I removed my seatbelt sensors on my 74 when I redid my seats. I believe they also prevented the car from starting unless the sensors felt the weight of a person sitting in the seat as well. But I also thought this was a one year 1974 feature the 75 didnt have.
I agree its probably the seatbelt buzzer.. I removed my seatbelt sensors on my 74 when I redid my seats. I believe they also prevented the car from starting unless the sensors felt the weight of a person sitting in the seat as well. But I also thought this was a one year 1974 feature the 75 didnt have.
1975 VINs 400001 through 402257 had functional seat belt interlock systems, like the 1974's. See the attached TSB. Note the last page of the attachment for the VIN info for Corvette. This TSB will be a part of the soon to be released 3rd edition of the NCRS 1975-77 Technical Information Manual and Judging Guide (TIM&JG)
Ernesto--please clarify your original post and provide a VIN for your car. This will help us to better help you.
Last edited by '73and'75; Jan 23, 2021 at 05:11 PM. Reason: spellin'
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My 75 is a 7742 build dated Dec 16th 1974, and if memory serves me right i disconnected the seat belt interlock system about 46 years ago, i could be wrong tho will have to check it out later.
Thank you 73and75 for the pdf. For some strange reason i already have this pdf from a post about 2 months ago think.
Thank you 73and75 for the pdf. For some strange reason i already have this pdf from a post about 2 months ago think.
