Voltage Reading
Thread Starter
Heel & Toe
Joined: Jul 2013
Posts: 18
Likes: 1
From: Ingersoll On
Voltage Reading
Hey guys. Sorry if this topic has been covered over and over again but can you kindly tell me what the voltage reading should be on display. My 2001's voltage is usually around 13.8 to 13.6 and i've seen it the odd time go up to 14.1 or .2 and then drop to 12.something. Have owned the car for only a month and a bit so I'm not sure if this is normal or not. I've had the System charge Default message show up approx. 6 times and i've the had the active handling disabled message appear yesterday. Also the passenger window goes up slowly.
Looking for the most likely suspect here.
My guesses are
1. Battery (fingers crossed for this one)
2. Alternator
3. Gremlins.
Any advice would be greatly appreciated.
Thanks,
Jay
Looking for the most likely suspect here.
My guesses are
1. Battery (fingers crossed for this one)
2. Alternator
3. Gremlins.
Any advice would be greatly appreciated.
Thanks,
Jay
Team Owner
Joined: Jul 2006
Posts: 22,201
Likes: 4,187
From: Kannapolis NC
Here's something to check for free. Check the battery cable ends for corrosion and make sure they're tight. Carefully check the large red wire from the battery at the starter solenoid. If it's loose or corroded, you'll get the fluctuating voltage and charge fault issues. I doubt that helps your slow window, but start with that.
Le Mans Master
Joined: May 2006
Posts: 6,774
Likes: 363
From: Midland TX
Hey guys. Sorry if this topic has been covered over and over again but can you kindly tell me what the voltage reading should be on display. My 2001's voltage is usually around 13.8 to 13.6 and i've seen it the odd time go up to 14.1 or .2 and then drop to 12.something. Have owned the car for only a month and a bit so I'm not sure if this is normal or not. I've had the System charge Default message show up approx. 6 times and i've the had the active handling disabled message appear yesterday. Also the passenger window goes up slowly.
Looking for the most likely suspect here.
My guesses are
1. Battery (fingers crossed for this one)
2. Alternator
3. Gremlins.
Any advice would be greatly appreciated.
Thanks,
Jay
Looking for the most likely suspect here.
My guesses are
1. Battery (fingers crossed for this one)
2. Alternator
3. Gremlins.
Any advice would be greatly appreciated.
Thanks,
Jay
However, if you are getting a "Charging System Fault" message, then that is NOT normal. I saw that for the first time in 13 years last month the day I replaced my alternator with a rebuilt (incompatible) unit. Do you have the original Valeo "Made in France" alternator still in the car (it will say on the alternator). If not, that may be the issue. I swapped that bad alternator out the next day and no "faults" since.
If just the passenger window goes up slowly and the drivers window works fine, then the problem is probably something unique to the passenger window system.
To diagnose the Active Handling System alert - pull and post your codes.
Thread Starter
Heel & Toe
Joined: Jul 2013
Posts: 18
Likes: 1
From: Ingersoll On
Battery connection are fine. No markings at all that I could see on alternator.
Checked battery voltage before turning on car 11.6
Checked display before turning on car 11.1
Voltage at battery after starting car 14.6
Voltage on display after starting car 14.1
(your bang on with the .5V higher at battery)
Yesterday when I drove the voltage was fluctuating between 13.6 and 13.7.
Im assuming these numbers tell me the battery and the alternator are both fine.
Gonna head to a shop and have them check for codes.
Thanks,
Jay
Checked battery voltage before turning on car 11.6
Checked display before turning on car 11.1
Voltage at battery after starting car 14.6
Voltage on display after starting car 14.1
(your bang on with the .5V higher at battery)
Yesterday when I drove the voltage was fluctuating between 13.6 and 13.7.
Im assuming these numbers tell me the battery and the alternator are both fine.
Gonna head to a shop and have them check for codes.
Thanks,
Jay
Melting Slicks
Joined: Jul 2013
Posts: 2,012
Likes: 23
From: Anaheim CA
Pro
Joined: May 2011
Posts: 580
Likes: 1
From: Chicago Suburb
St. Jude Donor '13
Battery? Alternator?
Battery connection are fine. No markings at all that I could see on alternator.
Checked battery voltage before turning on car 11.6
Checked display before turning on car 11.1
Voltage at battery after starting car 14.6
Voltage on display after starting car 14.1
(your bang on with the .5V higher at battery)
Yesterday when I drove the voltage was fluctuating between 13.6 and 13.7.
Im assuming these numbers tell me the battery and the alternator are both fine.
Gonna head to a shop and have them check for codes.
Thanks,
Jay
Checked battery voltage before turning on car 11.6
Checked display before turning on car 11.1
Voltage at battery after starting car 14.6
Voltage on display after starting car 14.1
(your bang on with the .5V higher at battery)
Yesterday when I drove the voltage was fluctuating between 13.6 and 13.7.
Im assuming these numbers tell me the battery and the alternator are both fine.
Gonna head to a shop and have them check for codes.
Thanks,
Jay
http://www.c5forum.com/ayc/dtcdic.php
Write down any codes that appear and post them. Codes with an "H" suffix are History; a "C" suffix is Current
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Thread Starter
Heel & Toe
Joined: Jul 2013
Posts: 18
Likes: 1
From: Ingersoll On
Very cool. Put a new battery in (while having my new Magnaflow exhaust installed) and drove home. Read this post when I got home and pulled codes. Nothing current at all but did see a 1214H which has to do with the Traction Control System. Guessing that this had to do with battery issue. Also a few left and right door control codes but again were Historical. Gonna drive her and enjoy.
Thanks again for all the help on here. Much appreciated.
Jay
Thanks again for all the help on here. Much appreciated.
Jay
Instructor
Joined: Dec 2010
Posts: 190
Likes: 0
From: Monroe, NC
Low Voltage
I have a similar problem with my 50th ann. vert.
I don't think I have a battery problem because the car can sit for a week and it starts right up. I never had any codes, but the voltage is low especially when it is hot. I get readings of less than 12V with the engine running. I never checked the voltage on a separate volt meter, I am just going by the gage and I get the same low readings on the DIC. Sometimes the readings are fine 13.5 to 14.1.
I am thinking a bad alternator. Any ideas?
I don't think I have a battery problem because the car can sit for a week and it starts right up. I never had any codes, but the voltage is low especially when it is hot. I get readings of less than 12V with the engine running. I never checked the voltage on a separate volt meter, I am just going by the gage and I get the same low readings on the DIC. Sometimes the readings are fine 13.5 to 14.1.
I am thinking a bad alternator. Any ideas?
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Your dash voltmeter is reading normally. The 0.5 volts difference is due to the voltage drop across the ign switch contacts and wires which is normal.
Car batteries are considered discharged if the no load terminal voltage is 12.0 volts or lower and these batteries should be charged up. New batteries will read 12.9 - 13v when fully charged. Dash voltmeters read lower than actual when the voltmeter is being operated by only the battery. Voltmeters read correctly when the alternator is keeping the electrical system at 13 to 16 (upper limit) volts. Don't leave batteries sit for long (4+ wks) because lead sulphate collects on the plates and ruins the battery. Always trickle charge or use a battery maintainer when car will sit for long periods. At least once a year you should disconnect the battery cables (neg first) and clean the battery posts and cable connectors and reconnect (neg last).
Car batteries are considered discharged if the no load terminal voltage is 12.0 volts or lower and these batteries should be charged up. New batteries will read 12.9 - 13v when fully charged. Dash voltmeters read lower than actual when the voltmeter is being operated by only the battery. Voltmeters read correctly when the alternator is keeping the electrical system at 13 to 16 (upper limit) volts. Don't leave batteries sit for long (4+ wks) because lead sulphate collects on the plates and ruins the battery. Always trickle charge or use a battery maintainer when car will sit for long periods. At least once a year you should disconnect the battery cables (neg first) and clean the battery posts and cable connectors and reconnect (neg last).
