Omega Owners Forum

Omega Help Area => Omega Electrical and Audio Help => Topic started by: countrywoman on 12 January 2021, 11:48:46

Title: wiring diagram clarification
Post by: countrywoman on 12 January 2021, 11:48:46
Have been getting my head around the wiring as stuck at home , cant get to my unit easy as road closed for patching and not going 10 miles extra to get there! Anyway started breaking down sections onto paper, window switches. Using rear switches for front and thats fine as colours the same , its just as not using master switch is the white  wire that goes to rear switches from safety (isolator?) switch a feed or ground .
Next is cooling blower for ECU /relay box, is that controlled by engine cooling fan switch and will I need it in my application in the Austin. I do want to fit ECU in passenger compartment but looks like the wiring will need extending , will see as not wanting to do that.
Title: Re: wiring diagram clarification
Post by: Doctor Gollum on 12 January 2021, 15:12:52
You're wasting your time with the ecu/fusebox fan. It was only fitted to the earliest of cars.

Between Haynes and the relay layout guide on here you should be able to figure out what's what as I presume you're losing the aircon.

The radiator switches ultimately override the ecu for the radiator fans. Also, the V6 Omegas were fitted with three fans for a reason.
Title: Re: wiring diagram clarification
Post by: countrywoman on 12 January 2021, 16:12:37
No air con ,its an ex plod car and only has one rad fan. More worried about the window switch, the dia of the switch does not help (the main one) as it looks like it has some diodes and a transistor so does the switch earth or feed the window motor. I suspect earth as there is a permanent live to motor .
Title: Re: wiring diagram clarification
Post by: Doctor Gollum on 12 January 2021, 16:20:00
It would have had two fans between the grill and the bumper and one between the radiator and the engine.
Title: Re: wiring diagram clarification
Post by: countrywoman on 12 January 2021, 19:09:22
Strange it only had the one behind rad.
Title: Re: wiring diagram clarification
Post by: Doctor Gollum on 12 January 2021, 19:38:41
Battle damage perhaps.
Title: Re: wiring diagram clarification
Post by: countrywoman on 12 January 2021, 21:34:52
Well it was old bill. Do you have any idea about window switch?
Title: Re: wiring diagram clarification
Post by: Doctor Gollum on 13 January 2021, 00:02:58
The driver's switch is the master, even if rears are manual.

Whether this matters on a pre/mid facelift car I couldn't say. Plod almost certainly had manual rear windows.
Title: Re: wiring diagram clarification
Post by: countrywoman on 13 January 2021, 08:57:56
No it had electric rears, using console rear switches for front. It was never a patrol car , the only clue is extra ariel fitting , calibrated speedo and chipped ECU . No sign of light bar but there were a few extra wires under headlining. Will make a dummy rig up to test motors and switch then. 
Title: Re: wiring diagram clarification
Post by: Doctor Gollum on 13 January 2021, 12:14:26
Retrofitting the rear windows was about two hours work, some parts and a fuse. Apart from the regulator rivets was completely plug and play.

And probably the most common ex plod mod along with leather interior.  ;)
Title: Re: wiring diagram clarification
Post by: countrywoman on 14 January 2021, 15:27:19
So need to ask do I need aux water pump , it will be getting a custom ali rad. Will the aux air pump set up a fault code if its removed (chucked it away ages ago)
Title: Re: wiring diagram clarification
Post by: Doctor Gollum on 14 January 2021, 16:13:45
On the radiator? Yes.

SAI will throw a code if not plugged in. Whether it is plumbed in or not is irrelevant, but the ecu expects to see it. There may be a cheat for it.
Title: Re: wiring diagram clarification
Post by: Nick W on 14 January 2021, 17:25:38
On the radiator? Yes.

SAI will throw a code if not plugged in. Whether it is plumbed in or not is irrelevant, but the ecu expects to see it. There may be a cheat for it.


There is. I can ask Ian how he did the one on his MGB.
Title: Re: wiring diagram clarification
Post by: GastronomicKleptomaniac on 14 January 2021, 18:44:34
You've piqued my interest... Tell me more about the donor car? :D
Title: Re: wiring diagram clarification
Post by: Nick W on 14 January 2021, 19:33:41
You've piqued my interest... Tell me more about the donor car? :D


manual 3.0l MV6


W plate MGB Jubilee
Title: Re: wiring diagram clarification
Post by: GastronomicKleptomaniac on 14 January 2021, 19:45:54
Yes, but I'd like to know about the ex-plod :D
Title: Re: wiring diagram clarification
Post by: countrywoman on 14 January 2021, 20:58:14
Came from a customer when I had a garage business , cam belt jumped when top roller collapsed. Got it for £50 for the wheels that I never used! ( still have the rims if anyone wants them) Kept it for 10 years before stripping all the bits I thought I would need . Its got a Vectra sump now to fit between the Austins chassis rails, yes it going in my hot rod.It will be essentially a Omega in a Austin chassis/body. Bit of a budget build due to lack of ££s. Think it might have been a CSI motor as no sign of it being a patrol car, either that or a plain /undercover job. Inside was immaculate as well in grey velour . Give aways as said , calibrated speedo, chipped ECU and extra ariel.