350 Amp Fuse
Thread Starter
Intermediate
Joined: May 2017
Posts: 37
Likes: 2
From: Kyle, Tx
350 Amp Fuse
Help!!!! I'm Wondering if I can pull a bunch of ideas on troubleshooting this issue.
Driving the car on a 6 hour drive and 4 hours in the car shuts off coasts off the road and the car goes dead, no dash, no power I had to use the emergency handle to get out. Did some looking and noticed the 350 amp fuse was blown in the back. A day later I installed the new fuse, Battery, and a starter thinking that could be the source of a short. the fuse blows as soon as I try to start I get no crank hardly anything except another blown fuse but I can refuse and it stays good dash comes on and I get all power back to everything until I give it a start. Car is a 2014 c7 stingray z51, it is modded headers, A&A TI blower, cammed, e85.
Thank you in advance I hate looking at the car just sit there.
Driving the car on a 6 hour drive and 4 hours in the car shuts off coasts off the road and the car goes dead, no dash, no power I had to use the emergency handle to get out. Did some looking and noticed the 350 amp fuse was blown in the back. A day later I installed the new fuse, Battery, and a starter thinking that could be the source of a short. the fuse blows as soon as I try to start I get no crank hardly anything except another blown fuse but I can refuse and it stays good dash comes on and I get all power back to everything until I give it a start. Car is a 2014 c7 stingray z51, it is modded headers, A&A TI blower, cammed, e85.
Thank you in advance I hate looking at the car just sit there.
Burning Brakes
Joined: Jan 2019
Posts: 954
Likes: 376
From: Louisiana
I would check service manual to see what circuits are tied into that 350A instead of guessing though.
Safety Car
Joined: Dec 2012
Posts: 3,838
Likes: 1,856
From: St. Louis Metro East IL
The starter appears to be the only load fused only by the 350 amp fuse. All other loads are powered through smaller sub fuses. From the wiring diagram attached, the starter power comes from the 350 amp fuse to the front fuse box, then the aux fuse box under the front fuse box, and to the starter. The 12 V should be hot to the starter at all times. The starter relay puts power the the starter solenoid (relay integral to the starter) when trying to crank.
I would trace the big red wire involved and see if it has a rubbed spot or bad insulation somewhere that could contact a ground when the trying to start or hitting a bump, etc.
GL
Ron
I would trace the big red wire involved and see if it has a rubbed spot or bad insulation somewhere that could contact a ground when the trying to start or hitting a bump, etc.
GL
Ron
Last edited by RonC7; Jun 18, 2024 at 09:13 AM.
Race Director
Joined: Aug 2015
Posts: 12,240
Likes: 4,738
From: SE WI
Also consider something binding in the engine or supercharger causing excessive starter current. Spun engine bearing, supercharger pulley binding, etc. Maybe take the belt off the SC and see if things turn freely.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
Melting Slicks
Joined: Feb 2018
Posts: 2,145
Likes: 1,026
From: North Texas
A seized engine is bad news and it doesn't always happen fast and violent.
Is your C7 stock?
If you can turn it over by hand its not seized 'tight'.
Oil and coolant levels haven't changed?
Did you have your torque tube replaced recently?
Ohm out the main power lead (Red) both connected and unconnected to the starter, removed from the battery of course. Wiggle the power cable watch the meter.
If you have a good supply of fuses, not my favorite troubleshooting method, disconnect the power lead to the starter, push the start button see if the fuse is still good. This would help you determine if the power cable is not shorting some where.
Removing the starter from the engine leaving all electrical connections attached, you will need to ground the starter. Then push the start button, if the starter spins and the fuse is still good you have eliminated, mostly, all of the starter circuit. But remember this test will not put any load on the starter so it won't be pulling a large amount of current. Also note you will need to secure the starter from twisting, it has a lot of torque when it first starts.
Or just take the removed starter to AutoZone and have it tested for free, simpler and safer.
Good luck.
Is your C7 stock?
If you can turn it over by hand its not seized 'tight'.
Oil and coolant levels haven't changed?
Did you have your torque tube replaced recently?
Ohm out the main power lead (Red) both connected and unconnected to the starter, removed from the battery of course. Wiggle the power cable watch the meter.
If you have a good supply of fuses, not my favorite troubleshooting method, disconnect the power lead to the starter, push the start button see if the fuse is still good. This would help you determine if the power cable is not shorting some where.
Removing the starter from the engine leaving all electrical connections attached, you will need to ground the starter. Then push the start button, if the starter spins and the fuse is still good you have eliminated, mostly, all of the starter circuit. But remember this test will not put any load on the starter so it won't be pulling a large amount of current. Also note you will need to secure the starter from twisting, it has a lot of torque when it first starts.
Or just take the removed starter to AutoZone and have it tested for free, simpler and safer.
Good luck.
Thread Starter
Intermediate
Joined: May 2017
Posts: 37
Likes: 2
From: Kyle, Tx
No its not stock. fluids are still same level and no torque tube changes. I did get a reading from the main lead going to the fuse box, starter, and alternator, showing 1mega ohm to ground it changed a couple of times in between 10-1 mega ohms so I'm leaning towards a short somewhere I'm not sure if that's a normal reading but correct me if I'm wrong but it should be showing open like the other cables to ground correct ? I already replaced the starter and same result
Thread Starter
Intermediate
Joined: May 2017
Posts: 37
Likes: 2
From: Kyle, Tx
Also anyone have the best way to turn the motor by hand ? the usual method with a socket or wrenches up front doesn't seem doable. I was thinking pulling plugs and jacking it up to rotate the rear tires
Burning Brakes
Joined: Jan 2019
Posts: 954
Likes: 376
From: Louisiana
Le Mans Master
Joined: Oct 2014
Posts: 8,672
Likes: 2,726
From: Atlanta GA
Melting Slicks
Joined: Feb 2018
Posts: 2,145
Likes: 1,026
From: North Texas
No its not stock. fluids are still same level and no torque tube changes. I did get a reading from the main lead going to the fuse box, starter, and alternator, showing 1mega ohm to ground it changed a couple of times in between 10-1 mega ohms so I'm leaning towards a short somewhere I'm not sure if that's a normal reading but correct me if I'm wrong but it should be showing open like the other cables to ground correct ? I already replaced the starter and same result
Going from 1 to 10 M ohms makes me think the meter needs a new battery or just a better meter.
You should not see this much of a change with out disturbing anything.
With both ends of the positive power cable disconnected, you should see infinite resistance, ie: an open to gnd. If you read any resistance at all you have a defective cable, ie: a short somewhere. Disconnected end to end the cable should read very low resistance ~ 2-5 ohms.
Burning Brakes
Joined: Jan 2019
Posts: 954
Likes: 376
From: Louisiana
No its not stock. fluids are still same level and no torque tube changes. I did get a reading from the main lead going to the fuse box, starter, and alternator, showing 1mega ohm to ground it changed a couple of times in between 10-1 mega ohms so I'm leaning towards a short somewhere I'm not sure if that's a normal reading but correct me if I'm wrong but it should be showing open like the other cables to ground correct ? I already replaced the starter and same result
Low resistance between 12V+ and chassis ground means a short. You can get nerdy and measure the wire resistance and subtract out from the reading, but just normal ohms should be enough.
Thread Starter
Intermediate
Joined: May 2017
Posts: 37
Likes: 2
From: Kyle, Tx
Update on the car. Blower is trashed, motor is still locked up. I sourced power through a power probe and it tries but wont budge. Gonna start the tear down and see what I find. Thank you everyone for the help and advice!!!
Le Mans Master
Joined: Oct 2014
Posts: 8,672
Likes: 2,726
From: Atlanta GA
Good luck and keep us posted , I can honestly say I know how you feel
Dave