Buzzer of doom

[molar38]

Help and advice please,
I have a 1.9 petrol engine which is water cooled, it has done 55000 miles from new and has been totally trouble free up til now. I use it almost daily and started her up as usual on our first real frosty morning this week. Having driven 20 yds the buzzer of doom sounded so i decided to use my other car as a precaution. Later on i checked the oil and topped it up (i am using correct oil as per the advice in Wikki) , when the van was running exactly the same happened again. I tried again today and left it on tick over to thoroughly warm it up, as soon as the revs increased it sounded again. The oil pressure was checked about 3 months ago and was fine. My questions are, do you think this is just an electrical issue or something more sinister,the garage i use is about 30 miles away, if problem is more severe am i ok to drive there ? I know there is no definitive answers but collective wisdom always helps. Does any one have experience of fitting oil pressure gauge which would bypass this poor warning system that seems to be full of inconsistencies. Any help and advice gratefully received.

[Aidan]

simple enough to check the basic wiring - disconnect the spade terminal from the high pressure switch in the block down by the pulley - can be difficult to do as it should be cable tied to the switch and the cable tie requires cutting, you can then open the plastic cover of the terminal (it's a flag type) and examine the spade terminal to check for obvious corrosion into the wire or break or poor connection, then connect the terminal to a good body or engine earth and then run the engine up to revs and if the buzzer sounds then it's a wiring issue, if it doesn't sound then it's either a poor physical connection to the switch, or the switch has failed, or you have insufficient oil pressure at 2000rpm; chances are it's a wiring issue. If it is you will have to work back through the wiring - check especially the 14 pin connection at the dash is solid, if still faulty then continuity check the wiring to the 14 pin connector and if this doesn't test good then check each section of wiring, so switch to 2 pin plug, 2 pin plug to 7 pin connector (iirc, it may not go through one of the 7 pin connectors, I don't have wiring diagram to hand) , 7 pin connector to fuse board, fuse board to 14 pin connector, 14 pin edge connector to bod circuit
wiring diagrams are online if you haven't got Bentley manual or Haynes, Syncrosport website is a good resource, they may even be in the tech info on the forum

[silverbullet]

Bad earth, either at the engine or gearbox braid and/or earth crowns under the lh end of the dash.
Poor connection at the dash pod ribbon connector is worth a look too.

[molar38]

Thanks guys, will check that out today, watch this space!

[itchyfeet]

I had a broken wire from loom to the switch, it measured ok with a multimeter so must have been an intermittant break when driving, new piece of wire fixed it.

buzzer only goes off over 2000rpm so it its happening cold when pressure is very high ( maybe 4 bar ) it will most likely be wiring or switch.
Where in soton are you?

[lodgey62]

Had exactly the same problem with mine,it was a broken wire on the spade connecter to the pressure switch behind the water pump,boy was I relieved to find that!hope yours turns out as easy.

[molar38]

Thanks, I am in Woolston not far from the toll bridge, not sure i will have time to look at it today but will certainly check out wiring and earths