H4 Relay's - Post Installation Question
 

I wired up the relays for the H4's on my car per many threads here. After the installation, the battery will go dead if the car sits for a week. It did not do this before. I connected a test light between the ground wire and battery and I know I have a power draw. If I remove power from the relays, the power draw is gone. So, I either have the relays wires wrong, or maybe, there is a problem with them. I have the relay's wired as follows:

Pin 85 - Ground
Pin 86 - Trigger from the light switch
Pin 87 - Power to the lights
Pin 30 - Power from battery (always on, this is the source of the power draw)

I am using two relays, one dedicated to low beam and one dedicated to high beam. Does anyone see a problem with the relays being wired as I outlined here?

It is not a big issue because I disconnect the battery if the car sits for a while, however, I know this should not happen. And yes I know the obvious answer - drive the car every day. :D

Thanks

I'm not sure if it is the same relay you have used, but from what I see you might have pins 85 & 86 swapped. Check out the following, and see if it is the same relay and clears anything up for you.

http://www.classictruckshop.com/clubs/earlyburbs/projects/bosch/relay.htm

Tom

Wait a minute, I might have steered you wrong in the last post. Here is another relay installation diagram I found, which appears to be the way you already have it wired.

Tom

Here's the diagram.

http://forums.pelicanparts.com/uploa...1063822015.jpg

Tom

Thanks for the info. Based upon what I see, I have it wired correctly. I am going to try isolating one relay at a time (I disconnedted both when checking the power draw) and see if one is bad.

Keith,

From your description it doesn't sound like there is any problem with your relay wiring or installation.

However, there may be a problem with your light switch or control stalk switch that is feeding current to the #86 terminal of your relay ... causing a drain on the battery, even if the current isn't enough to operate the relay! The DIN 'icecube' relays have coils with a resistance in the 70 - 100 Ohm range, and that represents enough current from ~12 Volts to drain a battery in one or two weeks.

I suggest checking terminal #86 at both relay sockets for Voltage presence with a digital multimeter while the relay is pulled and the ignition switch is off with the key out.

Warren,

Excellent idea, I never thought of that. I will look into that tonight and post my findings. Thanks!