Electrical gremlins
Thread Starter
Drifting
Joined: Jul 2020
Posts: 1,500
Likes: 323
From: San Diego
Electrical gremlins
I have twin electric fans and electric pop up headlights which earlier today were all working. Then suddenly my fans dont work and none of my lights work except my headlights but they dont pop up. I checked all fuses and relays and they are good but I am not getting any power at the fan relay so I have to chase wires. I hate electrical issues.
Thread Starter
Drifting
Joined: Jul 2020
Posts: 1,500
Likes: 323
From: San Diego
So running a test light, I get connections at all fuses except the second from the bottom on the right. It says directional signal/backup which makes sense but I get power on the right side, not the left although it doesnt look blown. Im going to pull it and check
Thread Starter
Drifting
Joined: Jul 2020
Posts: 1,500
Likes: 323
From: San Diego
So my electric headlights and twin electric fans were pulling power from the keyed hot for the backup lights under the hood and even though it did not look like it, the fuse was blown. I moved the power wire for the fans to the heater fuse in the fuse box since I do not have a heater and this fuse is not used. The original fuse was a 10A but I upped it to a 25A because the 10A blew immediately. I think this will be fine since I am only running the fans so in essence this is now my fuse specifically for my fans and not for my heater so I'm not overpowering a breaker. Does this sound right?
Team Owner
Joined: Jan 2007
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From: Southern Cal Ca
St. Jude Donor '22
So my electric headlights and twin electric fans were pulling power from the keyed hot for the backup lights under the hood and even though it did not look like it, the fuse was blown. I moved the power wire for the fans to the heater fuse in the fuse box since I do not have a heater and this fuse is not used. The original fuse was a 10A but I upped it to a 25A because the 10A blew immediately. I think this will be fine since I am only running the fans so in essence this is now my fuse specifically for my fans and not for my heater so I'm not overpowering a breaker. Does this sound right?
as long as the wires from the fuse can handle 25 amps
Thread Starter
Drifting
Joined: Jul 2020
Posts: 1,500
Likes: 323
From: San Diego
Thats a good point that I did not think about. Well the wire that I am running from the fuse box to the fans is a 10GA which should easily handle the 25A and since Im not running a heater there shouldn’t be any power running along the other wires.
Race Director
Joined: Mar 2017
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From: Virginia
But where are the relays getting their power?
I have a sub-panel in the engine compartment, with a fused connection to the starter. Fan relays connect to that, and there are extra slots for the eventual electric headlight conversion (and the headlights themselves).
I have a sub-panel in the engine compartment, with a fused connection to the starter. Fan relays connect to that, and there are extra slots for the eventual electric headlight conversion (and the headlights themselves).
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Thread Starter
Drifting
Joined: Jul 2020
Posts: 1,500
Likes: 323
From: San Diego
Can you send me a picture of what your sub panel or set up looks like? The relays are what the problem is because they are pulling alot of power.
My headlights are spliced in to the backup lights under the hood to pull keyed hot power and the fans were as well but it blew the fuse. I then pulled the dan relay off of that and I currently have it run to the heater fuse in the circuit breaker panel.
My headlights are spliced in to the backup lights under the hood to pull keyed hot power and the fans were as well but it blew the fuse. I then pulled the dan relay off of that and I currently have it run to the heater fuse in the circuit breaker panel.
Race Director
Joined: Mar 2017
Posts: 11,927
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From: Virginia
It's a big mess right now, attached to a non-AC fan/heater cover with a massive hole in it. But I followed @Richard454's wiring diagram, including the MRBF fuses.
In the C3 I used this Blue Sea Systems fuse block, and made my own 4 AWG cable. It has enough circuits that both fan relays can get their own fuse, with 6 circuits left over for headlights. The wires come out on one side. I've done similar installs with slightly different components in other vehicles. Depending on where you mount it, this Blue Sea fuse block may also be a good choice, with or without a common ground connection.
I'd look through this thread for inspiration and much better photos than my project car.
https://www.corvetteforum.com/forums...r-upgrade.html
In the C3 I used this Blue Sea Systems fuse block, and made my own 4 AWG cable. It has enough circuits that both fan relays can get their own fuse, with 6 circuits left over for headlights. The wires come out on one side. I've done similar installs with slightly different components in other vehicles. Depending on where you mount it, this Blue Sea fuse block may also be a good choice, with or without a common ground connection.
I'd look through this thread for inspiration and much better photos than my project car.
https://www.corvetteforum.com/forums...r-upgrade.html