Electrical problem

[Ford_V6]

I have a electrical problem on my 1982 Ford Transit 2.4 diesel pick-up.

It fires right away, but when I turn on the lights it takes quite some time before they start to just glow. Like a MagLite with very bad batteries.

But if I disconnect a grey or white wire on a relay in the engine compartment, the lights is fine. This wire goes from one relay to another relay. These 2 relays is mounted below my right hand battery. They have the same shape as the light relay in my MK4 Cortina.

But when this wire is disconnected, the glowing system isn't working.

Put the wire back in, the glowing system works fine, but the lights are bad again.

Is this just a case of bad earth, or is it more likely that one of the relays needs replacement?


Any help is greatly appreciated!

[Gunslinger]

glowing system .... huh


sorry you lost me here, but it sounds like something is draining power (current) from your lighting circuit, causing the lights to behave like they are connected to a 1950's generator

[Ford_V6]

My transit has glowplugs because it has the York engine.
I don't know any other way to desribe this in english, so I call it the glowing system.

So its most likely to be the light relay then?
Or the relay for the glowplugs?

[Gunslinger]

ok now i understand a little better, it sounds like one of the relays might have a problem, and is supplying power to the glow plugs, these draw a lot of current, and will cause the problems you are describing with the lights, also not to mention likely to wear out the glow plugs earlier than normal.

ok now as for your problem, if the glow plugs are getting power to them all the time, then either the relay or relays are knackered, or the system that tells the relays to switch has a problem.

unfortunately thats about as far as my knowledge off the top of my head goes

[Ford_V6]

ok now i understand a little better, it sounds like one of the relays might have a problem, and is supplying power to the glow plugs, these draw a lot of current, and will cause the problems you are causing with the lights, also not to mention likely to wear out the glow plugs earlier than normal.

ok now as for your problem, if the glow plugs are getting power to them all the time, then either the relay or relays are knackered, or the system that tells the relays to switch has a problem.

unfortunately thats about as far as my knowledge off the top of my head goes

Never thought about that though...

Maybe the best thing to do, is to change both relays anyway, just in case.
After all they have probably never been changed.

Thanks for the help!

[Gunslinger]

yeah they are cheap enough and will eliminate one thing from the list of stuff to check.

EDIT! its unlikely to be the light relay thats at fault. I dont know what triggers the relay for the glow plugs, hopefully someone else will hopefully be able to tell you that

[Caulky]

Hi,
Just had a quick look at the glowplug circuit. I used to have all of this stuff, but now have a 2.5di engine.

The glowplug timer relay is fed from the starter relay. The glowplug timer relay (grey wire) is also connected to the glowplug inhibitor thermoswitch.
It appears that the glowplugs are disconnected, when this switch kicks-in. (When the engine starts).

By the way you have described the problem, it looks as if the glowplug inhibitor switch is duff, not switching the glowplugs off. Taking the grey wire off when the motor is running, simulates the switch. I would say that the glowplug inhibitor thermoswitch, is permanently on. This means the glowplugs are also permanently on.
This switch screws into the block and needs replacing.

[Ford_V6]

Hi,
Just had a quick look at the glowplug circuit. I used to have all of this stuff, but now have a 2.5di engine.

The glowplug timer relay is fed from the starter relay. The glowplug timer relay (grey wire) is also connected to the glowplug inhibitor thermoswitch.
It appears that the glowplugs are disconnected, when this switch kicks-in. (When the engine starts).

By the way you have described the problem, it looks as if the glowplug inhibitor switch is duff, not switching the glowplugs off. Taking the grey wire off when the motor is running, simulates the switch. I would say that the glowplug inhibitor thermoswitch, is permanently on. This means the glowplugs are also permanently on.
This switch screws into the block and needs replacing.

I'll check it out.

By the way, where is this thermoswitch?

[Caulky]

Hi Ford_V6,

There are two thermo-switches screwed into the block. One is for switching the glow-plugs off, should have two grey wires attached.

The other one is the excess fuel switch (like a choke) for starting (2 black/Lt Green wires).

There are no pictures in my book, and as I said my engine no longer has glowplugs, cant help with the location.

Incidently, the glow-plug timer relay should only be active for about 30 seconds!

[Ford_V6]

Hi Ford_V6,

There are two thermo-switches screwed into the block. One is for switching the glow-plugs off, should have two grey wires attached.

The other one is the excess fuel switch (like a choke) for starting (2 black/Lt Green wires).

There are no pictures in my book, and as I said my engine no longer has glowplugs, cant help with the location.

Incidently, the glow-plug timer relay should only be active for about 30 seconds!

I'll see if I can find the wires first and then follow them to the block.
That's the easiest way I think.

Thanks a lot, Caulky!