electrical problems
Thread Starter
3rd Gear
Joined: Feb 2014
Posts: 3
Likes: 0
electrical problems
I went out to go for a cruise tried to start the car and found a dead battery. Replaced the battery started up and went out. I tried to turn on the radio and nothing no sound, display, nada! Cruised in silence drove to the car wash, hosed the dust off the garage queen cruised awhile longer and went home.
At the house checked the fuses, all good. Mystified I called it a day. Decided next weekend to go for a drive, got in the car and again DEAD BATTERY! Same drill replaced battery (free!), went for drive. On the cruise still no radio, but lights for door ajar and security would flash occasionally as well as lights on doors flickering as I drove.
Anyway battery won't hold a charge, (tested both battery and alternator good), fuses all good, radio doesn't work.
Anyone have an idea what might be going on?
At the house checked the fuses, all good. Mystified I called it a day. Decided next weekend to go for a drive, got in the car and again DEAD BATTERY! Same drill replaced battery (free!), went for drive. On the cruise still no radio, but lights for door ajar and security would flash occasionally as well as lights on doors flickering as I drove.
Anyway battery won't hold a charge, (tested both battery and alternator good), fuses all good, radio doesn't work.
Anyone have an idea what might be going on?
Race Director
Joined: Aug 2007
Posts: 11,889
Likes: 8
From: Whitefish Falls Ontario
St. Jude Donor '08-'09
First, you need to put a little more in your profile than that you are a male, vehicle year is always nice. The fact that your vette sits for extended periods would indicate that you have something that drains your battery.. To check this you need a meter.. Disconnect the negative terminal of the battery and connect the meter between the cable and the battery terminal, with the meter set to check for current.. If you get more than 50ma you need to start pulling fuses until you find where the excessive draw is..
Le Mans Master
Joined: Oct 2004
Posts: 6,314
Likes: 508
From: South-central Missouri
First, you need to put a little more in your profile than that you are a male, vehicle year is always nice. The fact that your vette sits for extended periods would indicate that you have something that drains your battery.. To check this you need a meter.. Disconnect the negative terminal of the battery and connect the meter between the cable and the battery terminal, with the meter set to check for current.. If you get more than 50ma you need to start pulling fuses until you find where the excessive draw is..
OP: Just to add...
Anytime a host of circuits start acting weird, I've found a good preliminary step is to check/clean the master ground terminals and clean them and coat them with some dielectric grease. Also check the battery connections, while you're at it. Once that is done, then if the problem hasn't gone away, at least you have addressed what usually causes 90(?)% of the multiple, "unrelated" (group) circuit failures.
Once that is done, then it is time to do as ccrazor suggested and start breaking it down. You'll need a FSM as well.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
You probably have a parasitic drain that's killing the battery.
Known culprits are: power antenna motor staying on, power seat motor stuck in "move" mode and not shutting off, headlight motor not shutting off.
Known culprits are: power antenna motor staying on, power seat motor stuck in "move" mode and not shutting off, headlight motor not shutting off.
Thread Starter
3rd Gear
Joined: Feb 2014
Posts: 3
Likes: 0
electric problems
Thanks for all the help last night in my haste to post my problem I did not mention the car is a 94' C4. I will try the parasitic draw test over the weekend when I have more time.
I've located three fuse boxes two in the engine compartment and one in the dash near the passenger door, are there any others?
I've located three fuse boxes two in the engine compartment and one in the dash near the passenger door, are there any others?
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
Measuring the battery drain is definitely a good thing to know and do.
But if the radio does not work at the same time the problem occurred I would follow that up.
Fuse 4 and 40 is for the radio, and fuse 37 is for the antenna. Does the antenna go up?
Fuse 40 controls the radio head. Display, memory, CD, and tape deck.
Fuse 4 turns on the radio head.
Confirm you cannot even see the time on the radio. Even if you push the volume control.
I know this is a strange question, but does the windows work when you shut down and take to key out of the ignition with the door still closed. Then, when door is opened, windows no longer work.??
But if the radio does not work at the same time the problem occurred I would follow that up.
Fuse 4 and 40 is for the radio, and fuse 37 is for the antenna. Does the antenna go up?
Fuse 40 controls the radio head. Display, memory, CD, and tape deck.
Fuse 4 turns on the radio head.
Confirm you cannot even see the time on the radio. Even if you push the volume control.
I know this is a strange question, but does the windows work when you shut down and take to key out of the ignition with the door still closed. Then, when door is opened, windows no longer work.??
Thread Starter
3rd Gear
Joined: Feb 2014
Posts: 3
Likes: 0
electrical problems
You gave me some good info all the fuses you mentioned check out as good. The display on the radio doesn't come on and the power antennae does nothing as well. As far as the windows they open and close when the car is off until the door switch is activated or triggered. I tried the parasitic drain test but
opening the hood triggered the under hood lamps and volt meter registered 0.00.
opening the hood triggered the under hood lamps and volt meter registered 0.00.
Measuring the battery drain is definitely a good thing to know and do.
But if the radio does not work at the same time the problem occurred I would follow that up.
Fuse 4 and 40 is for the radio, and fuse 37 is for the antenna. Does the antenna go up?
Fuse 40 controls the radio head. Display, memory, CD, and tape deck.
Fuse 4 turns on the radio head.
Confirm you cannot even see the time on the radio. Even if you push the volume control.
I know this is a strange question, but does the windows work when you shut down and take to key out of the ignition with the door still closed. Then, when door is opened, windows no longer work.??
But if the radio does not work at the same time the problem occurred I would follow that up.
Fuse 4 and 40 is for the radio, and fuse 37 is for the antenna. Does the antenna go up?
Fuse 40 controls the radio head. Display, memory, CD, and tape deck.
Fuse 4 turns on the radio head.
Confirm you cannot even see the time on the radio. Even if you push the volume control.
I know this is a strange question, but does the windows work when you shut down and take to key out of the ignition with the door still closed. Then, when door is opened, windows no longer work.??
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Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
You gave me some good info all the fuses you mentioned check out as good. The display on the radio doesn't come on and the power antennae does nothing as well. As far as the windows they open and close when the car is off until the door switch is activated or triggered. I tried the parasitic drain test but
opening the hood triggered the under hood lamps and volt meter registered 0.00.
opening the hood triggered the under hood lamps and volt meter registered 0.00.
The drain is a current measurement not a voltage measurement. You need to disconnect one of the battery terminals and insert the ammeter in series.
With the meter I used, I need to use the 10 amp range because the meter resistance (shunt resistance) is low and enables the car to "boot" up normally. When I used the 300ma range (meter resistance to high), the car was not "on" and could not get a valid reading and no lights would work. (Like battery not even connected).
You know when the car is "on" because you hear the headlight module internal relays start clicking and stabilize. On the 10A range, the resolution is not great for the current you want to read, but it will tell you if your pulling too much (more than 50 ma) or at a normal current draw.