Contour Enthusiasts Group Archives Forums General Troubleshooting Current Drain

Found a-n-o-t-h-e-r problem with this non-running '95 Contour SE, 2.5L w/atx.

Battery doesn't seem to hold its charge, so I ran a current drain test. With the courtesy lamp fuse pulled there is a 151 milliAmp current drain. (Shop manual says it should have no more than .05 amp - max!)

I started at the main fuse box (under the dash) and pulled each fuse one at a time and checked the current drain. No change! Then I proceeded to check the relays in the main fuse box. Bingo! When I remove the Courtesy Lamp Relay, (which was warm to the touch), the current drain drops to 3.6 milliAmps!

Testing this relay with a DVOM, it shows 76 ohms on the coil side and open on the switch side, which seems good to me.

After getting crosseyed trying to follow the wiring diagram, it looks like this relay is pulled in by the Central Timer Module, and at that point it provides the ground for the various courtesy lamps.

Since the CTM plugs into the back of the Main Fuse Panel, and the Courtesy Lamp Relay plugs into the top of the Main Fuse Panel, it doesn't seem that a stray hot wire could be energizing the relay.

(And I'm assuming the coil side of the relay is causing the current drain, as (V/R=I) 11.8 V/76 ohm = ~155 milliAmps, which is pretty close to what I was reading. Any thoughts on this?)

My questions are:

Does the Courtesy Lamp Relay appear to be good?
(Don't wanna change parts if nothing is wrong with 'em.)

Is there a way to determine if the CTM is functioning properly?
(Maybe the CTM is toast and is holding the relay in all the time.)

Is there something that I'm completely overlooking?

Welcome to CEG!

Pull the bulb in the trunk out and re-check.

Courtesy lamp relay will draw current when any door jam switch is in uncompressed(i.e. door open) state, even if Fuse 23 (courtesy lamps) pulled, since its coil receives feed from main 60 amp fuse.

Perhaps driver's door was open during your battery current check.

Remember now guys, I was measuring the current drain while the Courtesy Lamp fuse was pulled. That (at least according to my wiring diagram) shuts down the interior lights, the trunk, glove box, and underhood lights. That way I was able to work with the door open (how else ya gonna pull the fuses) and the hood up (to read the drain at the battery).

Now maybe the fact that the door was open, (even though the fuse was pulled), that may have told the CTM that the lights should be turned on, so the CTM pulled the Courtesy Lamp Relay in.

So tomorrow, with the Courtesy Lamp fuse pulled and the CL relay installed, I'll measure the current drain with the door opened, and with the door closed. (And for good measure, I do it with the trunk light installed, and with it disconnected.) Thanks for the ideas. . . . .

So my questions still are:

Does the Courtesy Lamp Relay appear to be good? Should the relay get warm just holding the coil in, even though it's not providing any current for the Courtesy Lamps? (Don't wanna change parts if nothing is wrong with 'em.)

Is there a way to determine if the CTM is functioning properly? (Maybe the CTM is toast and is holding the relay in all the time.)

Yes, yes. Coil has resistance therefore produces heat by-product, contact has theoretically no resistance therefore no heat by-product.

Yes (doubtful). Check my post here CTM self-test .

I don't know if these cars have one, but I assume they do: a ground strap/wire between the engine/alternator to the chassis.

Check the ground resistance between the engine/alternator to the chassis. It should be close to zero. If not, connect a wire or cable (even a jumper cable will work) between the alternator's ground (housing?) and the chassis.

If your amps draw decreases, there's a problem with the ground between the alternator and the chassis. In most cars (I don't know about these--I haven't studied the diagrams), the negative post of the battery is connected to the chassis; therefore, if the connection between the alternator and the chassis is bad, the alternator will not be able to keep the battery fully charged. As the engine and the rest of the car draw on the battery for power and the alternator is unable to keep up, the battery eventually gets drained.