Battery Drain on C4
Thread Starter
2nd Gear
Joined: Jan 2009
Posts: 2
Likes: 0
Battery Drain on C4
What could cause battery drain when everything is off and the car is just sitting overnight. When I tried to start it this morning I heard a noise appearing to come from the right side, under the dashboard close to the fuse box. I have been working on the car but disconnect the negative battery cable so as not to drain. Any suggestions?
GRB17260
GRB17260
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
What could cause battery drain when everything is off and the car is just sitting overnight. When I tried to start it this morning I heard a noise appearing to come from the right side, under the dashboard close to the fuse box. I have been working on the car but disconnect the negative battery cable so as not to drain. Any suggestions?
GRB17260
GRB17260
Often people have problem with the mercury switches in the center console door or with under hood lights.....they could be on all the time but you don't see them...kinda the same thing like wondering if the bulb goes out on the refrigerator door after it closes. Other things to look at would be stuck seat switches or other things that have power all the time.
The noise your hearing is most likely the blower motor for the digital AC/climate control unit....when the battery is almost drained or disconnect the AC defaults to run the AC blower mower.....reach over and hit the "off" button on the AC and see if the noise goes away.
Thread Starter
2nd Gear
Joined: Jan 2009
Posts: 2
Likes: 0
Sorry, I'm new at this. It is a 95 Coupe. It does not have climate control. The starter has been replaced, any possibility it could be the alternator? I thought it was just a bad battery so I took it out and had it checked. Of course they said all it needed was a charge which I had them do. The noise I hear is more of a soft clicking sound. Thanks for the reply.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
When I had my 92, I always turned the climate control system to OFF before shutting the engine down. Sometimes the BOSE relays may stay "hot" even after the ignition key is off.
You should check for current drains by placing a DVM in-line with the negative battery cable. Disconnect the negative cable and shut the driver's door. Find a way to push in the door jamb switch on the passenger door so that the interior lights go out and also disconnect the underhood lamps by removing the fuse from the holder.
Wait about 10 minutes before connecting the two leads from the DVM to the battery and the negative cable. Be sure to set the meter to mA (milla-Amps) before connecting the cables.
Note any current draw. At the fuse panel on the passenger side of the dash, remove one fuse at a time and note any drop in current. If you see a drop, that circuit should have something open causing the drain.
Sometimes a power seat relay can get stuck (common with C5's) and that can run a battery down quickly and also account for a noise.
You should check for current drains by placing a DVM in-line with the negative battery cable. Disconnect the negative cable and shut the driver's door. Find a way to push in the door jamb switch on the passenger door so that the interior lights go out and also disconnect the underhood lamps by removing the fuse from the holder.
Wait about 10 minutes before connecting the two leads from the DVM to the battery and the negative cable. Be sure to set the meter to mA (milla-Amps) before connecting the cables.
Note any current draw. At the fuse panel on the passenger side of the dash, remove one fuse at a time and note any drop in current. If you see a drop, that circuit should have something open causing the drain.
Sometimes a power seat relay can get stuck (common with C5's) and that can run a battery down quickly and also account for a noise.
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
When the battery voltage gets low enough, the anti-theft relay starts cycling (clicking). At night in a dark place, check for underhood lights, vanity mirror lights, door map lights, center console light, spare tire light. Never leave your key in the ignition because this keeps the anti theft circuit on and discharges the battery. Do you have a radar detector, CB, GPS, aftermarket alarm, radio, audio amplifier? Check em.
Pull the courtesy light fuse and remove the neg batt cable and connect an ammeter (VOM) from the neg cable to the neg battery terminal and switch down the ammeter from its highest scale until you can read the current. GM says leakage current should not exceed 50 milliamps. Pull one fuse at a time while watching the ammeter and one that dramatically drops the current is a circuit that will need further inspection. I believe on the 95's, there are some fuses near the battery, remove those one at a time too. Some circuits (like the alternator) use fuseable links and those need to be disconnected while watching the ammeter.
Pull the courtesy light fuse and remove the neg batt cable and connect an ammeter (VOM) from the neg cable to the neg battery terminal and switch down the ammeter from its highest scale until you can read the current. GM says leakage current should not exceed 50 milliamps. Pull one fuse at a time while watching the ammeter and one that dramatically drops the current is a circuit that will need further inspection. I believe on the 95's, there are some fuses near the battery, remove those one at a time too. Some circuits (like the alternator) use fuseable links and those need to be disconnected while watching the ammeter.
Instructor
Joined: Sep 2002
Posts: 156
Likes: 1
From: North Aurora IL
Does your battery have topside connecting posts on it? If so check to see if the arm holding the cruise control servo is resting on or contacting it, if it is that is definately not helping. Had that prob on my '94. Just a thought, hope it helps. Goood Luck!
7th Gear
Joined: Sep 2009
Posts: 7
Likes: 0
From: Webster NY
I have the same problem...95 coupe
The car has been sitting for about a 1-1/2 weeks. It was running fine but i wanted to re-dye the seats and fix the passenger window alignment so I did just that. When done I hooked everything back up...seats worked...windows worked...all interior lamps worked...today I tried starting it for the first time in about 10 days and it acted like the battery was dead...it tried to turn a little on the first try then it was basically dead (lights & seats & windows still work)...but the wierd thing was the clicking sound near the right side dash near the fuse box...I thought it might actually be in the fuse box. in any case, I have a battery charger on it right now but I would like to know what the clicking sound is and if charging should work...I realize that I may have drained the battery while working on the seats & window but am a little concerned it may be something else. Any thoughts on the clicking? It was even clicking when the keys were not turned.
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
The car has been sitting for about a 1-1/2 weeks. It was running fine but i wanted to re-dye the seats and fix the passenger window alignment so I did just that. When done I hooked everything back up...seats worked...windows worked...all interior lamps worked...today I tried starting it for the first time in about 10 days and it acted like the battery was dead...it tried to turn a little on the first try then it was basically dead (lights & seats & windows still work)...but the wierd thing was the clicking sound near the right side dash near the fuse box...I thought it might actually be in the fuse box. in any case, I have a battery charger on it right now but I would like to know what the clicking sound is and if charging should work...I realize that I may have drained the battery while working on the seats & window but am a little concerned it may be something else. Any thoughts on the clicking? It was even clicking when the keys were not turned.
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1st Gear
Joined: Feb 2018
Posts: 1
Likes: 0
From: Chandler Arizona
When I had my 92, I always turned the climate control system to OFF before shutting the engine down. Sometimes the BOSE relays may stay "hot" even after the ignition key is off.
You should check for current drains by placing a DVM in-line with the negative battery cable. Disconnect the negative cable and shut the driver's door. Find a way to push in the door jamb switch on the passenger door so that the interior lights go out and also disconnect the underhood lamps by removing the fuse from the holder.
Wait about 10 minutes before connecting the two leads from the DVM to the battery and the negative cable. Be sure to set the meter to mA (milla-Amps) before connecting the cables.
Note any current draw. At the fuse panel on the passenger side of the dash, remove one fuse at a time and note any drop in current. If you see a drop, that circuit should have something open causing the drain.
Sometimes a power seat relay can get stuck (common with C5's) and that can run a battery down quickly and also account for a noise.
You should check for current drains by placing a DVM in-line with the negative battery cable. Disconnect the negative cable and shut the driver's door. Find a way to push in the door jamb switch on the passenger door so that the interior lights go out and also disconnect the underhood lamps by removing the fuse from the holder.
Wait about 10 minutes before connecting the two leads from the DVM to the battery and the negative cable. Be sure to set the meter to mA (milla-Amps) before connecting the cables.
Note any current draw. At the fuse panel on the passenger side of the dash, remove one fuse at a time and note any drop in current. If you see a drop, that circuit should have something open causing the drain.
Sometimes a power seat relay can get stuck (common with C5's) and that can run a battery down quickly and also account for a noise.
Last edited by hookedonhiken; Feb 1, 2018 at 07:04 PM. Reason: added a better description of what fuse I pulled.
