Redhand Posted August 24, 2008 Share Posted August 24, 2008 I have a 1993 Disco 200tdi, It has a factory fitted immobiliser, and there are no aftermarket alarms immobilisers etc fitted It is absolutely Bog Standard. with no additional electrical items added. It has developed a problem the symptoms are. Will only drive when the hazard lights are switched on. If left for a while it will start occasionally. But will switch itself off as soon as you start to move or touch any switches etc. Won't switch off if the hazards are on. even if you're stood outside the vehicle with the keys in your hand. I've removed the fuse for the hazards and this stops the indicators flashing but means if you drive it you've no indicators I have disconnected all the wiring to the column switch gear and it doesn't make the slightest difference to the starting of the vehicle Once it dies you have to plug the connector with the hazard wiring in before it will restart. So I'm asuming it's the immobiliser and not the switch gear. Anyone heard of this happening before and how did you cure it... It has been suggested that the crash sensor has activated/failed. and that the cure is to hold the bonnet switch down while holding the key in the preheat glowplug position. This confused me as surely this happens everytime you start the vehicle anyway (the bonnet doing the job of holding the pluger switch down) Quote Link to comment Share on other sites More sharing options...
ThreeSheds Posted August 25, 2008 Share Posted August 25, 2008 Hi Redhand, I think maybe that it would be worth you searching this forum for the word 'spider'? Here's a good one to start with: linky Rog Quote Link to comment Share on other sites More sharing options...
Redhand Posted August 25, 2008 Author Share Posted August 25, 2008 Hi Redhand,I think maybe that it would be worth you searching this forum for the word 'spider'? Here's a good one to start with: linky Rog I thought the spider problem was restricted to 300tdi's... All the posts I've read on the spiders have all been 300tdi's Quote Link to comment Share on other sites More sharing options...
BogMonster Posted August 25, 2008 Share Posted August 25, 2008 AFAIK no spider on a 200 - it was only fitted on the factory 2 button alarm from 1996 on, it is not even fitted on the 1995 300Tdis Quote Link to comment Share on other sites More sharing options...
Redhand Posted August 25, 2008 Author Share Posted August 25, 2008 AFAIK no spider on a 200 - it was only fitted on the factory 2 button alarm from 1996 on, it is not even fitted on the 1995 300Tdis Cheers that was my understanding as well.. Quote Link to comment Share on other sites More sharing options...
ThreeSheds Posted August 25, 2008 Share Posted August 25, 2008 I thought the spider problem was restricted to 300tdi's... All the posts I've read on the spiders have all been 300tdi's Sorry to have mislead Rog Quote Link to comment Share on other sites More sharing options...
Redhand Posted August 27, 2008 Author Share Posted August 27, 2008 Sorry to have mislead Rog So that's the spider ruled out. Anyone else have any ideas what it might be.. Quote Link to comment Share on other sites More sharing options...
Comical Engineer Posted August 28, 2008 Share Posted August 28, 2008 So that's the spider ruled out. Anyone else have any ideas what it might be.. I suspect that it might be a short circuit in the wiring loom somewhere and / or a loose connection. I would perhaps try removing the wire from the fuel valve solenoid and running a separate wire and switch from the battery +ve to the fuel solenoid. This will at least allow you to start the engine and stop it without resort to pulling fuses. Note that short circuits can cause electrical fires! HTH Quote Link to comment Share on other sites More sharing options...
cipx2 Posted August 28, 2008 Share Posted August 28, 2008 ......Will only drive when the hazard lights are switched on. ..... You may want to elaborate on this a bit. When you switch on the ignition do the dash lights come on? If the dash lights don't come on when you switch on the ignition, do they come on if you engage the hazards? What happens when you turn the ignition key further, to the start position? The starter engages and the engine rotates but doesn't start? Or what does it do? Given the facts so far, my suspicion would be the ignition switch or something else (connectors/wires) on the +12V line between the battery and the fuel valve solenoid. On the other hand the hazards trick that you play there raises some questions. So I would disconnect the alarm (both connectors) so I can rule it out and see what happens (providing that I ground pin 86 from the starter relay). Then disconnect the glow plug timer relay. Now I would have the most basic starter circuit and it would be very easy to trace the fault. Quote Link to comment Share on other sites More sharing options...
Redhand Posted August 28, 2008 Author Share Posted August 28, 2008 You may want to elaborate on this a bit.When you switch on the ignition do the dash lights come on? If the dash lights don't come on when you switch on the ignition, do they come on if you engage the hazards? What happens when you turn the ignition key further, to the start position? The starter engages and the engine rotates but doesn't start? Or what does it do? Given the facts so far, my suspicion would be the ignition switch or something else (connectors/wires) on the +12V line between the battery and the fuel valve solenoid. On the other hand the hazards trick that you play there raises some questions. So I would disconnect the alarm (both connectors) so I can rule it out and see what happens (providing that I ground pin 86 from the starter relay). Then disconnect the glow plug timer relay. Now I would have the most basic starter circuit and it would be very easy to trace the fault. No dash lights unless Hazards are on. Yes they come on when you engage the Hazards Nothing happens unless the Hazards are engaged. I'm assuming that the Alarm is the black box above the fuse box behind the drivers side dash? If so I have disconnected it and it made no difference. Not tried playing with the starter relay. Only relay I can see is in the engine bay near the washer bottle. I have removed all the wires going to the switch cluster and it made absolutely no difference at all. It will start normally if left alone for an hour or so. but the fault returns as soon as you attempt to drive away. Quote Link to comment Share on other sites More sharing options...
cipx2 Posted August 28, 2008 Share Posted August 28, 2008 Here's the Starting electrical Diagram for a 1993MY Discovery 200Tdi (the second pic is the same as the 1st but with some ref points so that will be easier for me to explain): First step would be for you to make sure the fuel shut off solenoid ST9 gets power (+12V) after ignition on. That is to make sure you have +12V in all red points I marked in the diagram (3 & 4 - tested with ignition on). My guess is that at least in point 4 you don't get +12V unless the hazards is on. But forget about hazards for now. Leave it off and you will deal with it later. If you disconnect the alarm ECU you shouldn't be able to start the engine (but the dash should get illuminated and the cut off solenoid should get energized). Starter relay ST6 won't be grounded at pin 86 (left "on air" if Alarm ECU is missing) so no current through the coil when you will switch the ignition key to the START position => starter motor won't be engaged. So if you want to rule out the alarm, you need to ground pin 86 of the starter relay. But leave it in place for the moment. Yes, the alarm ECU is under the dash on the right side, it has 2 connectors (one of them with 6 pins in line and the other with 16 pins - 2 rows x 8 pins each row) and it looks about like this: It seems that it gets power through the hazards, possibly a short circuit of some kind, but the current isn't strong enough. You should attempt to do the tests when you can't start the vehicle normally and with hazards off. In case you do the test with a multimeter and nothing shows up (that is if you get +12V in all four points with ignition on), you may want to do the tests with a test lamp or something else that needs more than 3A to work (a headlight bulb, for example). Quote Link to comment Share on other sites More sharing options...
Redhand Posted September 1, 2008 Author Share Posted September 1, 2008 Cheers for that just going to go out and test it. I'll let you know how I get on.. Quote Link to comment Share on other sites More sharing options...
Redhand Posted September 1, 2008 Author Share Posted September 1, 2008 Solved the problem. Changed the left hand stalk/hazard switch, with one a friend gave to me to test it. Problem solved. If only everything in life was so simple. Quote Link to comment Share on other sites More sharing options...
Redhand Posted September 1, 2008 Author Share Posted September 1, 2008 Update that didn't last long. Now there's nothing at all even with the Hazards on?????? Back to the drawing board. Tried all the tests above ^^^ nothing no voltage at any of the points marked regardless of whether the immobiliser was unplugged or not. Got a live supply to the ignition switch but that goes as soon as you turn the key. Refitted old switch and it's back to the way it was before. Will work but only with Hazards on. I'm going to try and source another switch and see if that helps. If not I'm resorting to petrol and a matches.. Quote Link to comment Share on other sites More sharing options...
Smithers150 Posted March 21, 2022 Share Posted March 21, 2022 Hi, sorry for picking up an old thread but wondered if you managed to get this sorted? I have a similar issue with my 1993 Disco 3.5v8. bog standard, was working when last parked up but now won't start. No power after the ignition at all, no dash lights, only sides, hazards and interior lights. 12v at the ignition switch but when turned, it doesnt get any further... Have tested the ignition switch and it's fine. Feels.like it could be an earth fault but all the ones I have found seem to be ok! Quote Link to comment Share on other sites More sharing options...
Nonimouse Posted March 22, 2022 Share Posted March 22, 2022 In the drivers footwell are a number of nice big relays. one of these is the starting relay. The position varies and can sometimes be in the passenger footwell. Start there Quote Link to comment Share on other sites More sharing options...
Smithers150 Posted March 22, 2022 Share Posted March 22, 2022 Hi nonimouse, have tried the starter relay and it was fine, I actually had a spare new LR one and swapped it out just to be sure and still nothing. Have previously changed the fusible links for a 300 fuse box. Do the W and WO wires go into a connector after the ignition switch do you know? I have tried to trace them back but they just go into a tight bundle of pretty inaccessible cables under the dash... Quote Link to comment Share on other sites More sharing options...
Nonimouse Posted March 22, 2022 Share Posted March 22, 2022 3 hours ago, Smithers150 said: Do the W and WO wires go into a connector after the ignition switch do you know? I have tried to trace them back but they just go into a tight bundle of pretty inaccessible cables under the dash... Now there's a question I can't answer. Try the Project J facebook page - it's a very useful site. Ask Alan Young Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted March 22, 2022 Share Posted March 22, 2022 Disco 200TDI ignition switch and wiring loom: Ebay is your friend for things like that.... Quote Link to comment Share on other sites More sharing options...
Smithers150 Posted March 22, 2022 Share Posted March 22, 2022 Thanks Nonimouse Bowie69, tested ignition switch and it's fine. Unplugged it at the connector, put a jump wire between the brown on the loom and switch connector and tested the W and WO wire. Got battery voltage going back the way via both W and WO at the connector block, so the issue is downstream of the ignition connector block. It should he so easy but it so blooming frustrating 🤦 Quote Link to comment Share on other sites More sharing options...
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