Battery killing relay????
Thread Starter
8th Gear
Joined: May 2006
Posts: 8
Likes: 0
Battery killing relay????
Found the cause of my battery dieing after let the car sit fo a day or so. Found this relay thats mounted up under the dash on the passenger side...
{Shown with the plug inpluged}
Its draws about 1/3 of a amp when all the time. Even with no keys in the car. Thats what killing my battery. Everything works OK with it unplugged.
What is it for????
{Shown with the plug inpluged}
Its draws about 1/3 of a amp when all the time. Even with no keys in the car. Thats what killing my battery. Everything works OK with it unplugged.
What is it for????
Instructor
Joined: Dec 2002
Posts: 242
Likes: 0
From: Port Orchard Washington
That is a blocking/anti-dieseling relay. It is designed to place a load on the engine when turning it off to prevent run-on due to emissions/timing requirements of 1971. In non-AC cars it energizes the blower in high for five seconds, and in AC cars it energizes the AC clutch for five seconds, both cases when the key is placed to OFF.
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
sounds like the timer for that relay has died. The relay only gets power from the timer for a short time when you turn off the key. I saw a post in here somewhere just the other day on this circuit(I think)
Burning Brakes
Joined: May 2006
Posts: 763
Likes: 0
From: FBO Florida
Originally Posted by 71Vettehead
Found the cause of my battery dieing after let the car sit fo a day or so. Found this relay thats mounted up under the dash on the passenger side...
{Shown with the plug inpluged}
Its draws about 1/3 of a amp when all the time. Even with no keys in the car. Thats what killing my battery. Everything works OK with it unplugged.
What is it for????
{Shown with the plug inpluged}
Its draws about 1/3 of a amp when all the time. Even with no keys in the car. Thats what killing my battery. Everything works OK with it unplugged.
What is it for????
Thread Starter
8th Gear
Joined: May 2006
Posts: 8
Likes: 0
Originally Posted by 68AIR
Good job finding the problem and also with the difficult reverse angle kick panel photo. After you disconnected did your car quit after de-energizing the ign switch like before? Your underdash looks pretty original with what looks like an original 224 Tung Sol turn signal flasher.
in the "amp" mode! Put in line with the battery. Pulled fuses one by one with no luck. But it was the sound of the relay when I applied 12v to the system. The motor stopped fine.
Safety Car
Joined: Sep 1999
Posts: 4,930
Likes: 11
From: AnyTown NJ
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
If you don't have one get a Chassis Service Manual for 1971. Section 6T "Emission Control Systems" gives a good description of this somewhat complicated system.
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Thread Starter
8th Gear
Joined: May 2006
Posts: 8
Likes: 0
Originally Posted by Missileman
Note to all:
I still have electronic copies of the factory Emissions Control Troubleshooting manual for the 71 only system. Free to anyone that sends me a disk (too big to email).
I still have electronic copies of the factory Emissions Control Troubleshooting manual for the 71 only system. Free to anyone that sends me a disk (too big to email).
