I've Also had a combination of these sort of problems...
After loads of work looking at the mess of wires under the dash, I solved the
indicators by wiring in a seperate ground to the chassis as Richard said. (It
was
strange how they ever worked actually, as they were grounded to the fibreglass
quarter valences by the DPO!). A whole lot of other wierd stuff was solved by
tightening the earth connection on the diagonal brace by the battery and the
earth
onto the back of the speedo.
Cheers
Tim
Richard B Gosling wrote:
> Chip,
>
> Ooh, you have got a lot of fun with that car! I hate electrical problems, and
> at least my car has almost all original wiring, apart from a couple of minor
> mods I made (cigar lighter wire used as live source for radio and clock,
> extension to light switch wiring to enable switch relocation, so clock could
> go where light switch was). Wiring circuits should be reasonably logical,
>and
> you should be able to fix anything with a wiring diagram an patience, so any
> 'bodges' introduced by the PO are almost bound to be bad repairs to fix a
> fundamantal problem that, in all likelihood, still remains as no-one has ever
> tried to fix it properly.
>
> >From the start -
>
> Your lift indicator flashing while the dashlight stays on is very bizarre.
>One
> relay controls all the indicators - there should be a live to the relay, then
> the other side of the relay goes to the switch, which will connect to either
> the left or right lights, plus the dash light (this is from memory, I don't
> have the diagram in front of me, so I MIGHT be wrong - check the diagram).
> BTW, if you have the original drivers handbook from the car, the wiring
> diagram in there is easier to follow than the one in the Haynes Manual. In
> any case, the supply to the switch is already on/off, so how a permanent live
> can reach the lamp I have no idea - you will just have to take the lamp and
> follow the wire lighting it, and see where it goes.
>
> The left indicator not working when the headlights are on may be easier to
> solve. My guess is that the indicator is not properly earthed, and somehow
>is
> earthing via the headlights (maybe through the side-lights and/or brake
> lights). Thus, when the lights are on, the earth route is suddenly live, so
> there is nowhere for the electricity to go. Check the continuity from the
> front and rear bulbs to earth, and clean up the connections. You could
> install an extra earth wire connecting the lamp cluster casing to the car
>body
> just to be sure.
>
> Earthing problems can cause all sorts of problems that are hard to track down.
> Often the symptom bears very little connection to the cause (e.g. poor
> indicators caused by inadequatley earthed brake lights). You just have to
> check and clean all the connections. A useful method is to go round checking
> everything vaguely related to the circuit you are testing with a voltmeter
>(or
> one of those screwdriver-looking things with a light in the handle that just
> tell you if something is live), you will often bump into a wire that is live
> when you would not expect it to be, or vice versa.
>
> How the ignition light is connected should be clear from the wiring diagram.
> Off the top of my head, it should go between the live terminal of the
>ignition
> coil (or anything directly connected to that, including the ignition switch
> terminal, which would be easier), and the live terminal of the alternator.
> Thus, if the alternator is not generating anything, you have battery voltage
> one side, 0V on the other, bulb lights. When the alternator is charging you
> have full voltage both sides of the lamp, so no voltage drop across the bulb,
> so bulb stays off.
>
> I cannot see what the oil pressure warning light would have to do with the
> anti-run-on valve, or why they should be connected in any way. I cannot
>check
> right now on a wiring diagram, but I would expect that a live would feed to
> the bulb, which would then be connected to the switch. With no oil pressure,
> the switch would close the connection to earth (via cylinder block), bulb
> would light, with oil pressure the switch opens and the bulb does not light.
> I repeat, this would be my expectation, without ever having got involved with
> this circuit or looked at the diagram myself!
>
> Are you saying that your switch has a total of 3 connectors on it? Aah, I've
> had a thought about the anti-run-on valve - this may be an automatic cut-off
> device to protect you from your own incompetance - if the oil pressure drops,
> the anti-run-on valve would be activated, and that would kill the engine
> before any damage is done. The anti-run-on valve would probably just be a
> valve in the inlet manifold which would open to allow extra air in, to
>prevent
> the car running by weakening the mixture. This would normally operate when
> the engine is switched off to prevent that diesel-sounding rattley running
> that can continue for a few seconds after the ignition is off, particularly
> in a hot engine, or one with a lot of carbon build-up in the head. If you
> don't have a valve, don't connect the connector, everthing else will still
>run
> fine.
>
> As you might have gathered I am not a total expert in the field, but no-one
> else has replied yet, so I thought you might appreciate the benefit of my
> limited experience!
>
> Richard and Daffy (electrical gremlins were eventually tamed after 3 months of
> ownership, all fine since, touch wood(en dashboard))
--
Tim Dafforn
University of Cambridge
Structural Medicine Unit
Cambridge Institute for Medical Research
Wellcome Trust Centre for Molecular Mechanisms of Disease
Hills Rd, Cambridge CB2 2XY.
UK
Tel. (01223) 336829
Fax. (01223) 336827
http://smokeroom.cimr.cam.ac.uk/
|