Ignition/Stop oil & water lights comes on after warming

johnpaul2847 · Post by **johnpaul2847** » Tue Nov 02, 2010 12:26 pm

I have not removed the sensor / switch that appears to be causing the issue.

I have had to leave the car for a few days while I paint a friends house but due to go back to me dads and work on the car in the next few days.

Removing this wire from the sensor turns off all lights..

The glow plug light has stopped working in the passed and may not be connected to the current issue.

Thanks

electrokid · Post by **electrokid** » Tue Nov 02, 2010 6:53 pm

If the oil pressure goes low enough to bring the oil light on when the engine is on tickover then raising the rpm should raise the oil pressure enough to put the light out - so that's a test you can do.

The sensor switch is pretty cheap on ebay - this isn't the cheapest but the illustration looks right...

http://cgi.ebay.co.uk/50870-Oil-Pressur ... 483d5ca143

johnpaul2847 · Post by **johnpaul2847** » Tue Nov 02, 2010 8:38 pm

When these lights come on they do not go out by revving the engine once they come on they stay on until engine has been stopped but sometimes they do flicker while they are on... If they engine is restarted they are still on... when we had air pressure in the cooling system the rad light used to come on, if revved it would go out....

electrokid · Post by **electrokid** » Tue Nov 02, 2010 9:49 pm

Does the oil need changing because it's 8000 miles since it was last done - or does it need doing because no-one has thought about it before

Here's what I'm thinking - if the switch is after the filter in the oil circuit - and if the filter is getting blocked because the oil is mucky then that would be a reason for you to be losing oil pressure.

I'd be inclined to fit a new sensor because it's cheap - and change the oil and the oil filter because it needs doing anyway and if the filter is getting blocked and if the sensor comes after the filter in the oil flow then that might be the problem as well. And those are together cheaper than getting the water pump fitted.

Also the work on the HG might have left muck in the oilways which could possibly block the filter.

Post by **mat_fenwick** » Tue Nov 02, 2010 11:20 pm

Just had a rummage in my garage - I have a spare pressure switch. PM sent...

johnpaul2847 · Post by **johnpaul2847** » Wed Nov 03, 2010 9:33 am

Electokid I'm totally in agreement with that, oil filter blockage there is a new filter and oil to hand. There was a lot of cleaning involved to the block face as head gasket was changed twice in the end.. I'm going to do this when ?I get back to the car and the local parts shop has the sensor in stock for about £7 if I do need this after oil/filter change.

Since chatting to you in these forums, spoke to me dad and now the cars not starting up at all think the glow plugs might be a issue now, the light stopped working as I said now apparently needs a direct live to them to start it up, but when I was there it started fine my mind boggles with this BX

I will keep the forum posted

johnpaul2847 · Post by **johnpaul2847** » Wed Nov 03, 2010 9:36 am

Mat thanks for the kind offer on the switch ill reply to your PM about some other possible spares

johnpaul2847 · Post by **johnpaul2847** » Fri Nov 05, 2010 11:58 am

I am changing the oil/filter and the pressure switch today fingers crossed it solves the problems

johnpaul2847 · Post by **johnpaul2847** » Fri Nov 05, 2010 4:54 pm

is pleased to announce that after a 15 mile road test the Citroen BX is fixed at last

thanks for all your help the oil/filter and oil pressure senor has fixed the problem so far so good

the new issue with the glow plugs not working I have narrowed it down to the blue relay type thing under the bonnet bolted onto the N/S wing

tried local parts and can't be sourced atm... If anyone has a working spare please let me know

thanks again for your help with this problem

electrokid · Post by **electrokid** » Fri Nov 05, 2010 5:48 pm

well done $\:D/$

Now for the glowplugs...

You've found the blue thingy - good

Do you have a multimeter ?

Failing that find a car bulbholder for a small car bulb such as a sidelight bulb and attach a couple of wires to it so that when you put one wire to chassis and the other wire to the battery - the bulb lights - hey presto - you have a test lead.

There's a fat wire that joins all the tops of the glowplugs - you need to check to see if there is voltage getting to that wire when you turn the ignition on.

More later when you've got that far.

johnpaul2847 · Post by **johnpaul2847** » Fri Nov 05, 2010 6:23 pm

OK yer great stuff yer I have found the blue box following the lead back.. I do have a test light and there was now live at the glow plugs.. I used a jump lead and a screw driver from the battery and it started meaning no live.

I have tested both the black wires going into the blue box... There is a live going in but not one coming out wen the ignition is on.... I bridged the terminals to start it and the test light comes on along with the dashboard glow light.... So I believe this box has failed although I am going to try and clean the connectors up 2m when I replace the antifreeze ...

electrokid · Post by **electrokid** » Sat Nov 06, 2010 12:35 am

Yeah sounds like the blue box or a connection to it. Not had one of these fail but if I did I guess I'd be looking at fuse / connections / dry joints on the PCB and relay contacts.

johnpaul2847 · Post by **johnpaul2847** » Sat Nov 06, 2010 9:39 am

OK ill have a good look today and see what I can do.... In the meantime ill make up a piece of wire with two croc clips and it can be started first thing in the morning from the batt till I get the part

Thanks

johnpaul2847 · Post by **johnpaul2847** » Tue Nov 09, 2010 1:51 pm

I have cleaned up all the connectors on the blue box thingy with no results the blue box from Citroen is £140 so tried to get another from parts shop and it was the wrong type...so got one from the breakers from a Pug 406 is the same blue box with same connectors, but this is not working too only cost £10 so no issues there, so I'm assuming now there is a brake somewhere between ignition switch and this blue box..

There are two black wires one is a direct live all the time the other goes to the glow plugs and there is also a multi plug like a relay type connector I'm assuming its one of these smaller wires that must send a live signal to the blue box from ignition switch.

In the meantime we are using a length of wire with two crock clips direct to battery to heat up the plugs in the mornings

electrokid · Post by **electrokid** » Tue Nov 09, 2010 6:48 pm

Since you are not using either of your 2 blue boxes do you want to send them to me - I'll see if I can fix ?