1955 Draining battery with ignition off

[David Levitt]

My 1955 Tbird has recently started draining the battery when the ignition is off. I disconnected the clock many years ago. With ignition off there is a steady 0.13 amp current.
Is there anything else besides the clock that can be connected when ignition is off? Otherwise, I assume it must be a problem with the ignition switch.
Any help or advice would be greatly appreciated.

 

[cokefirst]

There should be no draw. The correct way of fixing this is to isolate each circuit in the car until the culprit is found. The easy way to solve the problem is to put a disconnect switch on it OR use a battery tender whenever you are storing the car for any length of time. These unknown current draws can be time consuming to locate.

 

[Ward 57]

I would start at your ignition switch. Disconnect it from the dash and just let it hang and then you can get to the contacts and test each circuit to find which is causing the draw.

 

[David Levitt]

Thanks. Is it hard to disconnect? Maybe you or someone could give me directions?

 

[Ward 57]

Thanks. Is it hard to disconnect? Maybe you or someone could give me directions?

It's pretty easy The bezel is held on with a chrome slotted bezel nut. There is a tool that fits the groves but you can always use some needle nose pliers to unscrew it if you are careful to not scratch it. once unscrewed the switch should just pull out from the dash and hang so you can get to the connections.

 

[jimntempe]

I think the Brake light circuit and horn relay both have power to them when ign is off. You can pull the wires off the brake light switch and see if that gets rid of the draw. Ditto for the power wire to the horn relay. If nothing shows up there there are a few fuses relatively easy to get to under the dash.. the radio (might be two, one for the light and one for the radio itself), heater blower, I think one for the clock. Don't think there is one for the cig lighter. Basically disconnect the easy stuff to get to either it's fuse or it's connector and see if the draw stops. Are your brake lights stuck on? Dash light stuck on? Courtesy light stuck on?

 

[swatson999]

Don't think there is one for the cig lighter.

If it's as originally installed, there is. It's a circuit breaker that threads onto the back of the cigarette lighter receptable, and then wire connects to that. It can be reset by pushing a paper clip into a small hole on the back of it. Unusual design, but you should *never* have a hot wire without circuit protection, so if it's missing, add it or put an in-line fuse in. If there's no protection and the lighter shorts out, it's a fire hazard.

 

[David Levitt]

If it's as originally installed, there is. It's a circuit breaker that threads onto the back of the cigarette lighter receptable, and then wire connects to that. It can be reset by pushing a paper clip into a small hole on the back of it. Unusual design, but you should *never* have a hot wire without circuit protection, so if it's missing, add it or put an in-line fuse in. If there's no protection and the lighter shorts out, it's a fire hazard.

 

[David Levitt]

Thanks for advice. If I can get my 80 yo body under dash, I will try to see if there are any current leaks at those sites. However, as I remember, only the head and tail lights were not turned off by ignition switch. I know the radio and heater blower was turned off, and I think the break lights also were. Anyone else with a '55 that can confirm what accessories are not turned off by ignition?

 

[doug7740]

The following are the items that are still operational when the ignition switch is turned off:

Clock
Interior light
Parking lights
Headlights (both high and low beams)
Instrument panel lights (only if the headlight switch is in the park or headlight position)
Brake lights
Horn
Cigarette lighter

doug7740
1955 Thunderbird Blue