Engine bay black box electrics

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Cataldoodledoo
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Engine bay black box electrics

Post by Cataldoodledoo »

Hi, I have an early 1985 VW T25 1.9l water cooled. The black box that houses the electrics in the engine bay, does anyone have a wiring diagram or is there another thread that explains all? Mines a mess and I have no idea where to start. Thanks.

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Re: Engine bay black box electrics

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Mocki
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Re: Engine bay black box electrics

Post by Mocki »

Is this any help?Lighting connector is as follows.
 T7/1 = Black / White for left indicator
 T7/2 = Black / Green for right indicator
 T7/3 = Black / Red for both brake lights
 T7/4 = Grey / White for the rear fog light
 T7/5 = Grey / Black for left tail light
 T7/6 = Grey / Red for right tail light
 T7/7 = Brown for chassis / earth for both rear clusters.
  
 Note that the reverse lights and rear number plate lights do not go from the seven pin plug.
 These are separate wires as follows.
  
 Reverse light wires are Blue / Black, to reverse switch and then to rear light cluster(s).
 And rear number plate wires are Grey / Green.
  
  
 The other 7 pin connector is as follows.
 T7a/1 = Blue / Black 0.3 bar oil pressure switch
 T7a/2 = Yellow / Red coolant gauge sender
 T7a/3 = Blue / Green low coolant level switch
 T7a/4 = Brown Sender unit common grounds
 T7a/5 = Green rpm / tacho signal
 T7a/6 = Red / Black terminal 50 supply
 T7a/7 = Yellow 0.9 bar or 1.8 bar oil pressure switch.
 (Dependent upon model, with dynamic oil pressure system - DOPS / buzzer of doom).
  
  
  
 Compiled by Robsey
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Cataldoodledoo
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Re: Engine bay black box electrics

Post by Cataldoodledoo »

Thank you!

Mocki wrote: 05 Apr 2021, 19:26 Is this any help?Lighting connector is as follows.
 T7/1 = Black / White for left indicator
 T7/2 = Black / Green for right indicator
 T7/3 = Black / Red for both brake lights
 T7/4 = Grey / White for the rear fog light
 T7/5 = Grey / Black for left tail light
 T7/6 = Grey / Red for right tail light
 T7/7 = Brown for chassis / earth for both rear clusters.
  
 Note that the reverse lights and rear number plate lights do not go from the seven pin plug.
 These are separate wires as follows.
  
 Reverse light wires are Blue / Black, to reverse switch and then to rear light cluster(s).
 And rear number plate wires are Grey / Green.
  
  
 The other 7 pin connector is as follows.
 T7a/1 = Blue / Black 0.3 bar oil pressure switch
 T7a/2 = Yellow / Red coolant gauge sender
 T7a/3 = Blue / Green low coolant level switch
 T7a/4 = Brown Sender unit common grounds
 T7a/5 = Green rpm / tacho signal
 T7a/6 = Red / Black terminal 50 supply
 T7a/7 = Yellow 0.9 bar or 1.8 bar oil pressure switch.
 (Dependent upon model, with dynamic oil pressure system - DOPS / buzzer of doom).
  
  
  
 Compiled by Robsey

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Re: Engine bay black box electrics

Post by Robsey »

That top grey / green looks a bit dodgy.
Should be your number plate light feed.

And it looks like someone spliced the wires for both oil pressure sensors together with a scotch-lock.
Blue/black and yellow wires.

I can see why you want to check out what each wire is for.
1983 Tin Top with a poorly DF and 4 speed DT box.
Soon to have a whizzy 1987 DJ.

Cataldoodledoo
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Re: Engine bay black box electrics

Post by Cataldoodledoo »

Robsey wrote:That top grey / green looks a bit dodgy.
Should be your number plate light feed.

And it looks like someone spliced the wires for both oil pressure sensors together with a scotch-lock.
Blue/black and yellow wires.

I can see why you want to check out what each wire is for.
Cheers! Will look at it all. I’m just no electrician, so hopefully not too hard.

And the oil pressure cables may explain why my sensor light doesn’t work in the dash!


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Robsey
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Re: Engine bay black box electrics

Post by Robsey »

A small correction...
The reverse light wire is black / blue...
Not blue/black....

Blue/black is the oil pressure wire.

Apologies if it caused any confusion.
1983 Tin Top with a poorly DF and 4 speed DT box.
Soon to have a whizzy 1987 DJ.

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Re: Engine bay black box electrics

Post by Cataldoodledoo »

So the red wire seems to go in the place of the black/white. Does that make sense?

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Re: Engine bay black box electrics

Post by Robsey »

It doesn't make much sense to me...
Unless the original black/white wire was faulty or not working properly.

That is for the indicator bulb on the left side.
1983 Tin Top with a poorly DF and 4 speed DT box.
Soon to have a whizzy 1987 DJ.

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