Relay layout

[Chase]

Antone have a layout for the relays on the car. I need to find the one that controls the key on items. I believe it's the body control relay.

 

[mikus]

The central locking control unit (body control unit, same thing?) is under the driver side dash, and is fed IIRC off the ALT fuse on main block.

Most interior lighting is off fuse #19 inside car, that fuse also sends switched power to ECU103

Switched power circuit to most of the engine bay follows > battery > sub fuse 20amp I forget position, it's marked > #10 on MPI > #4/5 MPI > ECU102 & 107 > all sorts of engine bay stuff

If you tell us a bit more about the specific problem maybe we can help better? If you have a battery drain it'd be ideal to know how large in mA and what fuse. Shoot me a line if you want to talk about how to determine this

 

[Chase]

Ok heres whats happening. Anything that works only when the key is in the on position stays on at all time whether the key is on or not even in the ignition. So all items such as the radio, dash clock, all the gauges since they are wired through radio power and ground wires and also things like the headlights and windshield wipers can be turned on with no key in the ignition. I have to use my battery shut off switch every time I get out of the car since it all stays on. So my assumption is that there's a relay stuck on somewhere or maybe I'm wrong but thats what I was told. I need to know which relay controls all those items that activate through the key in the on position so I can locate and replace it.

 

[mikus]

There's no single relay controlling all those items - power goes from the battery to the main fusible link (the 4-fuse jobbie on the battery) to the ignition switch in the dash, to... all over the place

Open this, actually save it down you'll use it. Go to 8-50, that's your ignition switch. Here you'll see:
- white +12V (3-W) coming in
- 4 lines coming out. If you look at where the lines originate in the top box, you'll see the key position. If you follow the line you'll see where power goes. That box at the bottom is the interior fusebox.

Pull ALL the fuses on interior fusebox. Now, with key=off, test for power at any fuse socket.
- If you have power the problem is before box (ignition switching issue likely)
- If you do not have power, likely someone has tied together a battery and switched +12V wire somewhere after the fusebox, introducing battery +12 to a circuit that should only have switched. Incorrect radio install is likely. You can selectively add fuses and test again to check each circuit, Eg. start by adding #19 (radio/interior light) and testing a socket.

EDIT: disclaimer I'm only so good at reading circuit diagrams so if anyone disagrees please speak up! This will only take a few minutes to test either way

 

[Chase]

Ok so the stuff will turn off when pulling fuses 4 and 8 on the interior. Those are the remote controlled mirror switch/cigarette lighter and the headlight relay/horn. So that really doesn't make sense to me considering 17 which is the MPI control unit is the one that is supposed to control all of the key on hot stuff. I'd just pull the fuse and see if it's fine but i have no idea if my battery will still drain.

 

[mikus]

Here's a link to the interior fusebox, first off my bad as quite a bit of this is battery power so original input was not right. Sorry, dumb mistake in retrospect. Mine's in storage so no chance to "field test" input.

To be clear, you're experiencing constant power to:
radio, dash clock, aftermarket gauges, headlights and windshield wipers

And when you remove, on the FSM image above, fuses 4 and 8, none of those items are powered with key off anymore?

First do we know where your radio/gauges take power from? Did you put it in?

Second didn't you have a headlight power issue previously on this car? What was the resolution, and do you believe wires have been 'messed with' in the headlight circuit? Specifically could the source of power to the headlights have changed?

Hunch right now is radio/gauge power source wiring is at least part of the problem.

 

[StyleFresh125]

i wanted to know wat happen with the headlight, im having headlight problems now

 

[Chase]

I dont know with the headlight. I wired it to the good side.