C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

Power door locks not working

Thread Tools
 
Search this Thread
 
Old May 2, 2026 | 09:41 PM
  #1  
Bugly87's Avatar
Bugly87
Thread Starter
Pro
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Aug 2011
Posts: 504
Likes: 117
From: Allentown Pa
Default Power door locks not working

Hello all,

I purchased my 1992 Corvette coupe 2 years ago. The power door locks do not work. I dug into the issue today and did a search here. I have power at the main accy fuse located at the passenger side fuse panel. Tested it with my cigarette lighter which worked. Located the power door lock fuse under the passenger side hush panel. I found that it was blown. Replaced it and hooked up the door lock switches on each side (the door panels are off). The door locks still do not work. My questions are: Do all of the door electronic connectors need to be connected for the door locks to work? If not, I will test for power at the plunger connectors. I can't get my fat hands inside the panel to disconnect the connecter. Is there a way to do this or do I have to drill out the rivets to get the plunger motor out?

Thanks for any suggestions as always,

Regards,

Kevin
Reply
Old May 3, 2026 | 11:02 PM
  #2  
IHBD's Avatar
IHBD
Melting Slicks
All Eyes On Me
Shutterbug
Top Answer: 5
Pro Mechanic
 
Joined: Nov 2016
Posts: 2,256
Likes: 3,082
From: So Cal
2023 C4 of the Year Finalist - Unmodified
Default

Both door lock switches have to be connected for the locks to work. If either is unplugged, neither side motor will work from the remaining switch.
Reply
Old May 4, 2026 | 09:29 PM
  #3  
Bugly87's Avatar
Bugly87
Thread Starter
Pro
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Aug 2011
Posts: 504
Likes: 117
From: Allentown Pa
Default

IHBD Thank you for the response. I will drill out the actuators tomorrow and test the connections for power. Then new actuators probably anyway.

Regards,

Kevin
Reply
Old May 4, 2026 | 09:44 PM
  #4  
IHBD's Avatar
IHBD
Melting Slicks
All Eyes On Me
Shutterbug
Top Answer: 5
Pro Mechanic
 
Joined: Nov 2016
Posts: 2,256
Likes: 3,082
From: So Cal
2023 C4 of the Year Finalist - Unmodified
Default

You don't have to drill out the lock motors to test.

At the driver switch the orange/black is hot at all times. Comes from the Fuse in the aux fuse box.

The gray wire is (+) to UNlock. (-) to LOCK.
The tan wire is (-) to UNlock and (+) to LOCK.

You need to apply power to one of the wires and ground to the other. The gray and tan wires go directly to the lock motors.

Another validation check: When the tan wire gets a (+) pulse, the SECURITY light should go Solid-On. The alarm is armed. When the gray wire gets a (+) pulse, the SECURITY light should go back to flashing (with a door open), the alarm is disarmed.
Reply
Old May 6, 2026 | 12:34 AM
  #5  
Bugly87's Avatar
Bugly87
Thread Starter
Pro
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Aug 2011
Posts: 504
Likes: 117
From: Allentown Pa
Default

Thank you again IHBD. I will try this diagnostic soon as I can. Rain all day tomorrow. Today was put in a new water pump in my 2011 Escalade.
Thank you again for the diagnostic steps,

Regards,
Kevin
Reply
Old May 20, 2026 | 09:17 PM
  #6  
Bugly87's Avatar
Bugly87
Thread Starter
Pro
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Aug 2011
Posts: 504
Likes: 117
From: Allentown Pa
Default

I got the chance to check for power at the lock plungers per IHBD's suggestion. The plungers reacted as they should. Very nice and strong open and close. I am going to clean up my switch contacts and try them again. If they don't work it's off to get new switches.

Thank you again IHBD for the straightforward testing procedure.

Regards,
Kevin
Reply
Old May 25, 2026 | 03:26 PM
  #7  
Natty C's Avatar
Natty C
Melting Slicks
Community Builder
Community Influencer
Community Favorite
Top Answer: 1
 
Joined: May 2019
Posts: 3,237
Likes: 1,403
From: Mid-Atlantic
2025 C4 of the Year Finalist - Unmodified
2023 C4 of the Year Finalist - Unmodified
2022 C4 of the Year Finalist - Unmodified
2021 C4 of the Year - Unmodified Finalist
Default

I'd pop these open and give em a look before replacing the switches. Its hinged, so opens right up so you can see if the connections are being made inside or are otherwise broken.



As is clearly visible, some of mine were not.

That's where power comes from and is dispersed for the window switches.

If you find any bad ones, I'll find the source I used for those oddball repair terminals inside if needed.


Last edited by Natty C; May 25, 2026 at 03:35 PM.
Reply
Old May 26, 2026 | 12:12 AM
  #8  
Bugly87's Avatar
Bugly87
Thread Starter
Pro
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Aug 2011
Posts: 504
Likes: 117
From: Allentown Pa
Default

Thank you Natty for the info and offer. I will be out of the State on Wednesday through Sunday and unable to check till I get back. It's a great suggestion as I can see one or two of my wires backing out. I will check when I get back and report back.

Regards,

Kevin
Reply
Old May 26, 2026 | 01:52 AM
  #9  
Natty C's Avatar
Natty C
Melting Slicks
Community Builder
Community Influencer
Community Favorite
Top Answer: 1
 
Joined: May 2019
Posts: 3,237
Likes: 1,403
From: Mid-Atlantic
2025 C4 of the Year Finalist - Unmodified
2023 C4 of the Year Finalist - Unmodified
2022 C4 of the Year Finalist - Unmodified
2021 C4 of the Year - Unmodified Finalist
Default

Originally Posted by Bugly87
Thank you Natty for the info and offer. I will be out of the State on Wednesday through Sunday and unable to check till I get back. It's a great suggestion as I can see one or two of my wires backing out. I will check when I get back and report back.

Regards,

Kevin
Well good luck with it, whatever the problem turns out to be. I found the thread where I was trying to figure out what those terminals were called, btw.

These are the terminals...



Here's where I got em. He keeps em in stock...

​​​​​​https://www.ebay.com/itm/15561149390...Bk9SR6jE1faKZg

If it turns out that you do have a problem with those, guaranteed you'll destroy a couple of em while crimping them, so consider that. I bought 10 and only have three left. lol...

Also, good idea to take a cell phone pic of the terminal/wire color layout once you pop the hinge open on that connector. They fall out easy and you'l be left guessing which ones go where.

They sell aftermarket pigtails, imported from China, but the wires are different colors. Another good reason to take a pic when you pop the connector open, if you were to go the pigtail route instead. They looked kind of cheap and flimsy to me, though, so opted to repair the original connections with new terminals instead.

A few wires were only hanging on by one or two corroded strands of wire.


Last edited by Natty C; May 26, 2026 at 12:54 PM. Reason: Typos...
Reply
Old Today | 02:34 PM
  #10  
Bugly87's Avatar
Bugly87
Thread Starter
Pro
10 Year Member
Liked
Loved
Community Favorite
 
Joined: Aug 2011
Posts: 504
Likes: 117
From: Allentown Pa
Default

Update:
I was able to work on my 92's power door locks. Per Nattys good advice I checked the pigtail wires and connectors on each side. The drivers side seemed fine...no broken or frayed wires. The terminals were clean. I squeezed each one together to ensure a good connection and closed the cap. Checked the passenger side and saw a bit of corrosion on the orange terminal and the black wire adjacent. I've attached a photo although it did not turn out too good. I carefully sanded and scraped these two terminals to a shine. All the other wires were fine. Squeezed them together and closed the cap. Squeezed on the new switches and viola....nothing. Tried several times no luck. I re-checked the fuses under the hush panel and all were good. I then re-checked the connectors on each side per IHBD's good advice. I was able to jump the wires and the door locks worked like I dreamed that they would. I also tried the old switches and no luck.

So Natty...could the terminals that you replaced look good but still be bad? That may be my only solution although the locks should work. Anyone have any other suggestions?

Kind Regards,

Kevin
Reply

Get notified of new replies

To Power door locks not working





All times are GMT -4. The time now is 03:53 PM.