Parasitic Battery Drain
Thread Starter
Intermediate
Joined: Mar 2013
Posts: 25
Likes: 0
Parasitic Battery Drain
Hey guys, trying to chase down a large parasitic battery drain that will leave the battery lower then 12V and unable to crank after a few hours.
Here is what I know :
1. Measure amps between Neg post of batt and Neg cable , large draw 170..
2. Alternator rebuilt last month , remove all connections from Alt , no change.
3. No change when pulling fuses.
4. Remove first two wires of hot solenoid post (not the large one form the POS Battery post) and the drain goes away.
5. After much searching wondering if the Courtesy Light Switch is a culprit ? Interior lights all work , but will not turn on when door is opened only work at light switch when switched to on. leads me to think maybe that Courtesy Light Switch is shorted which would explain why no lights come on when the doors are opened ?
Where is that Courtesy Switch on 1974 ?
Anything else I may be missing?
Thanks all!
Here is what I know :
1. Measure amps between Neg post of batt and Neg cable , large draw 170..
2. Alternator rebuilt last month , remove all connections from Alt , no change.
3. No change when pulling fuses.
4. Remove first two wires of hot solenoid post (not the large one form the POS Battery post) and the drain goes away.
5. After much searching wondering if the Courtesy Light Switch is a culprit ? Interior lights all work , but will not turn on when door is opened only work at light switch when switched to on. leads me to think maybe that Courtesy Light Switch is shorted which would explain why no lights come on when the doors are opened ?
Where is that Courtesy Switch on 1974 ?
Anything else I may be missing?
Thanks all!
Thread Starter
Intermediate
Joined: Mar 2013
Posts: 25
Likes: 0
Think I found it, when the courtesy light fuse is removed, the drain is gone...
This is the courtesy switch for the 1974 , I looked all over the drivers side door and can not find this little thing! Where is located?
This is the courtesy switch for the 1974 , I looked all over the drivers side door and can not find this little thing! Where is located?
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
You might want to considering ordering one. The AIM shows the door jamb switches, lists the old original GM part numbers, shows how they were installed, and the wiring to each. If memory serves, the driver's side switch is also used for the factory theft alarm.
Thread Starter
Intermediate
Joined: Mar 2013
Posts: 25
Likes: 0
If you have that page you can share , the one that shows the location and how to access the switch , that would be very helpful!
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
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Burning Brakes
Joined: Sep 2012
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From: coon rapids mn
my battery drains over nite if I don't disconnect it .maybe I will disconnect the lite switches in the door .the lite goes out in 30 seconds .I should take a meter to the fuse box and find the battery drain.
Le Mans Master
Joined: Aug 2006
Posts: 7,426
Likes: 1,559
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
If you need that switch get it and the wire connectors from a vendor as they are Corvette only terminals.
Do your courtesy lights go on when you turn the k *** full left and do the dash lights dim buy turning that K *** with the lights on?
Are you sure the light in the rear center compartment is off with the door down?
Le Mans Master
Joined: Aug 2006
Posts: 7,426
Likes: 1,559
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Your year has a delay timmer that seems to go bad a lot and kill the battery. Have you checked that part?
Le Mans Master
Joined: Oct 2002
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From: You are here to build strength, not demonstrate it
St. Jude Donor '08
To get to the wires that connect to that switch remove the sill plate and then remove the kick panel.
If you need that switch get it and the wire connectors from a vendor as they are Corvette only terminals.
Do your courtesy lights go on when you turn the k *** full left and do the dash lights dim buy turning that K *** with the lights on?
Are you sure the light in the rear center compartment is off with the door down?
If you need that switch get it and the wire connectors from a vendor as they are Corvette only terminals.
Do your courtesy lights go on when you turn the k *** full left and do the dash lights dim buy turning that K *** with the lights on?
Are you sure the light in the rear center compartment is off with the door down?
OK, my question might fit in here.
My 71.
the dash / gauge lights and console lights never worked. (I've owned the car only about 6 months)
I was under the dash and I broke the original drivers side door switch.
The courtesy lights always worked
Ordered 2 new ones, installed them.
-how the heck do the clips or prongs on the wires stay in the switch??
I doubt they used crazy glue at the factory
headlights work fine, but still no gauge lights. fuse is fine.
where to begin looking for a short???
Le Mans Master
Joined: Aug 2006
Posts: 7,426
Likes: 1,559
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
OK, my question might fit in here.
My 71.
the dash / gauge lights and console lights never worked. (I've owned the car only about 6 months)
I was under the dash and I broke the original drivers side door switch.
The courtesy lights always worked
Ordered 2 new ones, installed them.
-how the heck do the clips or prongs on the wires stay in the switch??
I doubt they used crazy glue at the factory
headlights work fine, but still no gauge lights. fuse is fine.
where to begin looking for a short???
My 71.
the dash / gauge lights and console lights never worked. (I've owned the car only about 6 months)
I was under the dash and I broke the original drivers side door switch.
The courtesy lights always worked
Ordered 2 new ones, installed them.
-how the heck do the clips or prongs on the wires stay in the switch??
I doubt they used crazy glue at the factory
headlights work fine, but still no gauge lights. fuse is fine.
where to begin looking for a short???
http://www.zip-corvette.com/ProductD...L2-SR&CTitle=&
and zip e-413 terminal connectors
http://www.zip-corvette.com/ProductD...L2-SR&CTitle=&
For the dash and gauge lights jumper from ''courtesy light fuse" to "instrument light fuse", if the bulbs light up then the rheostat in the headlight switch is bad.