C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

No accessory power

Thread Tools
 
Search this Thread
 
Old Apr 28, 2020 | 04:24 PM
  #1  
76Stingray@Mikes's Avatar
76Stingray@Mikes
Thread Starter
Navigator
 
Joined: Apr 2020
Posts: 9
Likes: 0
Default No accessory power

Hello, I purchased this 76 Vette slightly disassembled and have almost complete it. It has a new wiring harness in the cab that the previous owner installed. I am having problems getting power to my heater fan, windows wiper. There is no power at the fuses nor the actual switch. I have power to start the car and lights and when it runs, same thing no power to accessory's. Any help would be appreciated. I would like to say that I am new to these forum's. Hope I posted it in the right place.


Last edited by 76Stingray@Mikes; Apr 28, 2020 at 04:27 PM.
Reply
Old Apr 28, 2020 | 04:28 PM
  #2  
Vetteman Jack's Avatar
Vetteman Jack
Administrator
Supporting Lifetime
Veteran: Navy
St. Jude 20 Year Donor
25 Year Member
Veteran: Reserves
 
Joined: Mar 2001
Posts: 368,340
Likes: 24,779
From: In a parallel universe. Currently own 2014 Stingray Coupe.
C7 of the Year - Modified Finalist 2021
MO Events Coordinator
St. Jude Co-Organizer
St. Jude Donor '03 thru '26
NCM Sinkhole Donor
CI 5, 8 & 11 Veteran
Default

Moved to C3 Tech/Performance.
Reply
Old May 1, 2020 | 02:36 PM
  #3  
RedTRex's Avatar
RedTRex
Racer
10 Year Member
 
Joined: Aug 2011
Posts: 494
Likes: 138
From: Chesapeake, VA
Default

Well assuming it is the correct harness, you should have all the info you need in your wiring harness link to track down the issue. https://docs.google.com/viewer?a=v&p...2E5ZTkxMTc1NmY

looks like lights are powered by orange which is probably hot all the time.

my guess is the ignition switch (electrical side) is malfunctioning and not giving you accessory power
Reply
Old May 1, 2020 | 03:20 PM
  #4  
twinpack's Avatar
twinpack
Drifting
15 Year Member
 
Joined: Mar 2009
Posts: 1,461
Likes: 361
From: Monson MA
Default

I just went through with my 68. In my case I had no power to the wiper, heater and radio. All the power to those currents comes from the ACC wire. Theis wire is powered in ACC a d run position. I found the wire in the fuse box was disconnected. Reconnected, power on all 3. Just a thought. I know there is a big difference between our years but I bet the theory hasn't changed.
Reply
Old May 1, 2020 | 08:30 PM
  #5  
76Stingray@Mikes's Avatar
76Stingray@Mikes
Thread Starter
Navigator
 
Joined: Apr 2020
Posts: 9
Likes: 0
Default

Thanks for the info guys really appreciate it, I just pulled the harness off the engine compartment side and noticed there was a prong pushed in and bent. Also noticed two wires cut coming off of it i did some power test and see that there is juice there. I will be doing some investigating and check where they all go. Probably going to change out the engine harness anyways as its starting to look really bad. I will make sure to keep you updated.
Reply
Old May 9, 2020 | 04:55 PM
  #6  
76Stingray@Mikes's Avatar
76Stingray@Mikes
Thread Starter
Navigator
 
Joined: Apr 2020
Posts: 9
Likes: 0
Default

So a little update. I found the problem for the windows and the heater. I was watching a video on you tube and they had shown a relay that was hidden under the tachometer cluster screwed to the floor. It was missing on mine. I put one in and boom it worked. The same thin goes with the heater. There is a relay on the engine wall where the wires connect, I pulled the connectors off and bypassed the power and bingo bango the heater worked. Like I said before the harness is in really bad shape so I will be ordering a new one. I have a couple of of wires cut off the harness that I believe feeds the windshield washer motor and I believe that it all has to be connected to complete the connection. You can correct me if I'm wrong.

Also I have 2 wires that come of the harness that feed the lights that are equipped with two rings one is orange and one is pink, they are molded together. Can someone tell me what they are for?

Thank you

Last edited by 76Stingray@Mikes; May 9, 2020 at 04:57 PM.
Reply
Old May 9, 2020 | 04:56 PM
  #7  
76Stingray@Mikes's Avatar
76Stingray@Mikes
Thread Starter
Navigator
 
Joined: Apr 2020
Posts: 9
Likes: 0
Default


Reply
Old May 9, 2020 | 05:16 PM
  #8  
Peterbuilt's Avatar
Peterbuilt
Le Mans Master
15 Year Member
 
Joined: Aug 2006
Posts: 7,426
Likes: 1,559
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Default

Do you have a circuit breaker mounted on the firewall next to the power booster?





Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

10 Ugly Corvettes That We Still Kinda Love

 Joe Kucinski
story-1

Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

 Brett Foote
story-2

10 Things Every Corvette Owner Needs (2026 Edition)

 Michael S. Palmer
story-3

8 Most "Only Corvette Owners Understand" Quirks and Problems

 Pouria Savadkouei
story-4

10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

 Joe Kucinski
story-5

How Much Horsepower Every Corvette Engine "LOST" in 1972

 Joe Kucinski
story-6

Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

 Michael S. Palmer
story-7

Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

 Joe Kucinski
story-8

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-9

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
Old May 9, 2020 | 05:31 PM
  #9  
76Stingray@Mikes's Avatar
76Stingray@Mikes
Thread Starter
Navigator
 
Joined: Apr 2020
Posts: 9
Likes: 0
Default

I just checked I do not.
Reply
Old May 16, 2020 | 11:08 AM
  #10  
76Stingray@Mikes's Avatar
76Stingray@Mikes
Thread Starter
Navigator
 
Joined: Apr 2020
Posts: 9
Likes: 0
Default



Can someone tell me what these are for? All lights are connected.There is one on each side off the light wiring harness.

Last edited by 76Stingray@Mikes; May 16, 2020 at 11:12 AM.
Reply

Get notified of new replies

To No accessory power





All times are GMT -4. The time now is 02:13 PM.

story-0
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-1
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-2
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-3
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-4
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-5
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-6
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-7
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-8
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-9
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE