Blower & Wiper Problem

[tmossa]

Help. I have a 1993 Escort and the wipers work and the fan runs with the ignition switch shut off and key out. This drains the battery dead. I have disconnected the wires to the ignition switch to see if the switch was bad and still have the same problem. Any ideas?

[AzTumbleweed]

Heater fan or engine cooling fan?

[tmossa]

Originally Posted by AzTumbleweed

Heater fan or engine cooling fan?

It's the heater blower.

[tmossa]

Where can I get a wiring diagram?

[AzTumbleweed]

I'm still trying to follow you. Do you mean the heater motor and wipers run even with their switches turned off? Or do they run with the ignition off IF their switches are on? I'm looking at my Haynes manual. Not much of a schematic but it's something. The only thing I know of that would do this is a froze relay. Maybe an ignition relay? But the manual isn't too clear. As far as I know the only way these two items can get power with the key off is from a stuck relay.

[tmossa]

The switches work fine. I can turn on the heater blower and the wipers with the key switch turned off. This is draining the battery when it is parked. Does it say where these relays are located? I did unplug the wiring from the ignition switch but they still turn on so the relay is probably my problem.

[AzTumbleweed]

Originally Posted by tmossa

The switches work fine. I can turn on the heater blower and the wipers with the key switch turned off. This is draining the battery when it is parked. Does it say where these relays are located? I did unplug the wiring from the ignition switch but they still turn on so the relay is probably my problem.

If the wiper switch is off and the heater switch is off then there would be no reason for these two items to drain the battery since they would be drawing no power. My point is, there is power going to other places too. That's what's killing the battery. I'm mean something like the fuel pump, ignition system, etc. I think if we find the mystery relay then it will resolve your problem. I think there is an "IGNITION' relay under the hood in the fuse box. Unhook that and see if it kills the power to your wipers/heater.

[tmossa]

Here's the latest. The only relay in the power distrubution box under the hood is a cooling fan relay. I turned the fan on with the key off and began unplugging all the relays I could find. Found two on passenger side fire wall, two behind consol on passenger side floor and four up above the fuse box on drivers floor. None of these shut the the fan off. When I pulled the 10amp fuse for the rear wiper, the fan shut off but the rear wiper still runs with key off. When I turn the key on the heater blower and front wipers work properly. With key off and rear wiper fuse out I no longer am drawing power from the battery but the rear wipers still run with key off. Any more Ideas?

[AzTumbleweed]

The rear wiper will run with the fuse removed

This is a challenging one. My car is a wagon and I guess hatchbacks are the same but there is an electrical cable that goes from the car to the hatch. On my wagon it's to the upper right as you are standing behind the car. The wiring harness was messed up on mine. Broken wires and missing insulation from age. Maybe there is a problem there. Some wires are touching each other that shouldn't be. This is an interesting problem. Keep letting me know what happens. Really curious!

[AzTumbleweed]

I've been looking at my Haynes Manual and scratching my head. It does show a wire going from the rear wiper fuse to the heater control. Go figure that one out! Looks like it may have something to do with A/C. Not sure. But all of these wires are supposed to be dead with the key off. Including the rear wiper.

I found an 'ignition relay' but it looks like it's only purpose is to turn off the engine cooling fan when the engine is off. They love to confuse us!

All I can say is there are a group of wires (minus some insulation) that are touching somewhere. At least one of the wires is HOT with the key off.

There are several wires coming out from under the engine compartment fuse box. Some of them go between the battery and wheel well. See if battery acid has gotten on them. The resulting loss of insulation might be the problem.

Also look at the hatch door like I posted earlier. The wire for the hatch's interior light is hot all the time. If it came in contact with the wire for the wiper motor then it would make it run. That's why the wiper motor can run without a fuse. It's being powered by the lighting circuit. The fan cuts off when you remove the wiper fuse because it's being powered by that circuit. It's 'backfeeding' I think is the word. I think my cable was messed up right there where it bends everytime you open the hatch.

Another thing to try is remove the fuse for the interior lights and see if that kills the rear wiper. If so then my theory is correct. This should be the fuse on the bottom center of panel Labeled "ROOM".

[tmossa]

Yes, pulling the Room fuse did stop all the things (blower and wiper) from running with the key off. I am now looking at the wiring going to the hatch. Thanks for getting me this far. I'll let you know what I find!

[tmossa]

I checked all the wiring going from the body to the hatchback, Looks like that has been a problem before and has been repaired but I see no wires touching. I checked all wires with a meter and I'm showing 12 volts on all three blue wires. One has a green trace on blue, one has a red trace on blue and the other is black trace on blue. None of the other wires have voltage. This is checked with the 10 amp room fuse back in the fuse box and wiper and blower running with key off. Should all three of these wires have 12 volts?

[AzTumbleweed]

I'll look at a schematic after I have another gallon of coffee this morning but I would think only the wire for the interior light would have power with key off. It does appear that the interior lighting circuit is powering the other stuff. I think we're getting warm.

[AzTumbleweed]

Here's what I have gathered from my Haynes manual:

Black/Dark Blue----------Rear Window Defrost
Dark Blue/Dark Green-----Rear Wiper Motor
Dark Blue/ Red-----------Interior Light
Red/Black----------------License Plate Light
Dark Green---------------Hi Mount Brake Light
Black--------------------Ground
Red/Yellow---------------Turns on "Lift Gate Ajar" Light

Does your interior light work on the hatch? Mine didn't used to. Found a broken switch inside the hatch by the latch. I just by-passed it. So now I turn the light on and off with the little rocker switch by the light.

[tmossa]

Does the room fuse control anything important or just the dome and hatch light? Can I just leave the room fuse out? Also where is the ignition relay located? This is really giving me a headach!