oil pressure sending unit

[Huw Powell]

> Sorry to disagree with you Huw but BTDT just recently on an 89 200tq:

Strange, although my original message is gone, what you say below agrees 
exactly with whatever I would have said.  This is how every Audi I have 
owned is set up (prior to autocheck, there was a standalone oil pressure 
warning relay driving a warning light).

Any car without the oil pressure gauge has the "simpler" two separate 
switch setup.

> The 89 and up type 44 chassis has a different dashboard with some extra 
> gauges including oil pressure but the block still has only two oil 
> pressure ports. These two ports were previously occupied by a low 
> pressure switch (closes below 0.3 bar) and a high pressure switch 
> (closes above 1.8 bar). Both feed into the auto check computer along 
> with rpm. If the auto check computer doesn't see the correct switch 
> opened/closed at the correct rpm you get the oil pressure warning 
> symbol. When the oil pressure gauge was added VDO invented a combined 
> the sender for the gauge and the 0.3 bar low pressure switch in one 
> housing so as to maintain the auto check functionality while providing 
> the signal to run the gauge separately. The two contacts on the oil 
> pressure sender/switch are labeled accordingly as G for gauge and S for 
> switch. The high pressure switch (white body) stays unchanged.

-- 
Huw Powell

http://www.humanspeakers.com/audi

http://www.humanthoughts.org/