Technical Wiring diagrams. Help

[Marc Lewis]

Hi all. Can anyone help me with wiring diagrams please? I'm trying to trace the circuit for the oil pressure switch and oil pressure warning light. The diagram in the Haynes manual is pretty poor!


Any help will be much appreciated. Thanks


Marc Lewis

 

[flisko]

are you sure its called oil pressure switch? as i cant find anything in autodata only thing it shows is oil level switch

1.2 8v?

 

[Ziggy122]

are you sure its called oil pressure switch? as i cant find anything in autodata only thing it shows is oil level switch

1.2 8v?

There is only 1 wire to the switch

Its got a positive feed to it - when oil pressure is too low - it earths out = Full circuit

IF the oil pressure is high enough - it open circuits = light out

All autodata says is oil level switch - which i think the incorrect name
I think its meant to say oil pressure switch

Going from ECU pin 23 connector A

The Canbus system will most likely then control the dash board

Ziggy

 

[flisko]

this

 

[Ziggy122]

yea - mine says same flisko

I've never seen a punto with an Oil level switch/sensor

An Oil pressure sensor yes - it stick oppersite side to the oil filter

Ziggy

 

[Marc Lewis]

Thanks guys. It's a 1.2 16v. Defiantly an oil pressure switch, not oil level.
So I am right in thinking that the warning light is controlled by the ECU?

 

[flisko]

Thanks guys. It's a 1.2 16v. Defiantly an oil pressure switch, not oil level.
So I am right in thinking that the warning light is controlled by the ECU?

yea 1.2 16v got oil pressure switch, we were assuming you got 8v

 

[AndyRKett]

It's a modern canbus car so the switch is connected to the engine Ecu which is then digitally connected to the rest of the canbus system. When the oil pressure drops the engine Ecu will put that information on the canbus network digitally and any modules such as the dashboard which uses that information will pick it up and translate it into something you'll understand like putting a warning light on.

Basically it's not a simple single wire connection between a switch and a light anymore and the best way to fault find is with a copy of MES And a laptop plugged in to directly see what the oil pressure switch is doing.

 

[Ziggy122]

It's a modern canbus car so the switch is connected to the engine Ecu which is then digitally connected to the rest of the canbus system. When the oil pressure drops the engine Ecu will put that information on the canbus network digitally and any modules such as the dashboard which uses that information will pick it up and translate it into something you'll understand like putting a warning light on.

Basically it's not a simple single wire connection between a switch and a light anymore and the best way to fault find is with a copy of MES And a laptop plugged in to directly see what the oil pressure switch is doing.

i meant for how it works where it power comes from (ecu) and earths

But yes dash is canbus'd

Ziggy

 

[Marc Lewis]

Ok. So my Dad had an OBD2 scanner, so I plugged it in and managed to switch the oil pressure light off. I guess that the switch had failed and in turn made the light come on. Even after fitting a new switch, the light was still on. That is what threw me off and confused me, didn't realise that the switch/light is controlled by ECU and needed to be turned off.


Anyway, problem solved and all is good. Thanks for your help everyone. Appreciated.


Marc Lewis