I have a 1987 3 Door Sierra Cosworth.
The interior lights, stereo and cigarette lighter currently don't work.
I know they are all linked and the fault will be common.
Checked all fuses, renewed/cleaned all battery wiring connections.
Now with my limited knowledge I am stuck on the cause.
Any suggestions I could try to remedy?

 

If like the MK2, everything you mention (along with central locking) is protected by the same (20 A) fuse.

I would advise you use this as a starting place to see if power is present.

Martin

 

Thanks Martin.
Checked fuse and power is present.
Also central locking works fine still.
I am still stuck tho

 

Ok, so on the premise that the central locking IS from the same supply (you need to check, MK2 certainly is) then we need to work further forward, there may be a wiring break.

Does the interior light have power?

Kind regards,

Martin

 

Hi Martin
I will check tomorrow and see , thank you
Jas

 

Ive tested the interior light, cigar lighter etc and it shows there is a very low current getting through, I think it could be a dodgy earth. Where is the earth to cover these items?

 

I assume you mean current, not voltage?

Neither of these will draw much current and don't share a common earth.

The earth for the interior light is the door switches, which actually trips a timer relay in this case (courtesy lighting).

I don't believe this to be the issue, but you could always run a test earth if you wanted to.

Martin

 

Still no joy, any other suggestions I could check?

 

The last update you stated low current, you surely mean voltage.

You haven't provided any further information, such as the voltage you measured?

Martin

 

Not really 100% with testing everything tbh, ok fixing things but finding them is another issue

 

No worries, so you state you measured voltage at the light, what is the reading you got and how did you measure it?

Martin