I have a 2002 model TD5 which has always started first time a piston compresses. This morning when I went to start after waiting for the lights, including the glow plug light to go out it did not leap into life. I went to heat again but there was no glow plug light. I tried to start it but it just wound but never attempted to fire. I noticed there was a small glow from the cruise control dashboard switch light. Also the rear screen heater light was not working which it had been the evening before. I checked all fuses and obvious wiring but found nothing. When I then put the ignition on the small glow had vanished in the cruise control switch and my glow plug light came on. The car then started fine. After 3 or 4 starts with no problem I left the car for an hour. When I went back the glow was back on the cruise control, the glow plug light did not come on and the car would not start again. I checked everything again including pulling the cruise control fuse but with no result. Even with the fuse pulled the small glow continued. Has any one any idea where there might be a connection between the cruise control, the heated rear window, the heater plug light and the firing of the engine. Any one with any ideas of any sort please HELP.
Wiered electrical starting fault
- Thread starter Dozy Land
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Bromsgrove Defender
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I don't have a Disco TD5 wiring diagram.
I suggest you download one and start hunting with a multimeter, it's either going to be a poor earth but more likely a short somewhere between said items.
First point of call would be a point of commonality ie a header joint, a place where the loom goes through a bulkhead or other potential chaffing point.
If that throws up nothing obvious you'll have to follow each wire from the battery to each suspect item.
Happy hunting
I suggest you download one and start hunting with a multimeter, it's either going to be a poor earth but more likely a short somewhere between said items.
First point of call would be a point of commonality ie a header joint, a place where the loom goes through a bulkhead or other potential chaffing point.
If that throws up nothing obvious you'll have to follow each wire from the battery to each suspect item.
Happy hunting
Bromsgrove Defender
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Where do you wanna start lol
Ok start at the battery
Ignition,
Starter motor,
Fuel pump relay,
fuel pump,
main relay,
ECU,
immobiliser
No power to any one of the above and you int going nowhere
never mind the various sensors
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sierrafery
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connection between the glowplug light and the cruise controll light is in the the ECM(engine ECU) and the wires are in the black plug... the engine harness used to get damaged especially the wires which are going into the black plug. The HRWindow has no connection with these.... So or it's a wiring issue or its a fault inside the ECM. Many measurements are required with the diagram in front so if you are not good with electrics it's quite hard... what you can do is to unplug the ECM black plug and give it a contact spray... you can check for oil in the red plug too meanwhile... if you find much oil there's the possibility that it got into the ECM and made some damage
Mr Noisy
Coming in your ears.
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I wrote this and then saw that it could be the ECU not the BCM!
*****
More likely a BCM fault tbh, if anything.
Actual wiring loom faults are rare.
Remove the BCU from under the drivers seat IIRC and open it up, look carefully for any evidence of water damage and check the connectors for it too.
We must try not to get ahead of ourselves though, sometimes as these problems are simpler than we expect.
Plus, d2 can do odd things, putting the transmission warning light on I think when you have a brake light out.
The faint glow doesn't sound healthy though but I wouldn't suspect the loom personally, not when there's electronics involved...
Cheers
*****
More likely a BCM fault tbh, if anything.
Actual wiring loom faults are rare.
Remove the BCU from under the drivers seat IIRC and open it up, look carefully for any evidence of water damage and check the connectors for it too.
We must try not to get ahead of ourselves though, sometimes as these problems are simpler than we expect.
Plus, d2 can do odd things, putting the transmission warning light on I think when you have a brake light out.
The faint glow doesn't sound healthy though but I wouldn't suspect the loom personally, not when there's electronics involved...
Cheers
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Bromsgrove Defender
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Good call
I think the fact that these faults occured at the same time says electrical fault to me. Just the not starting then yeah maybe the ECM.
As for the oil in the red plug. Yes get it sorted but I'd be very surprised if that was the reason behind these faults
Bromsgrove Defender
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I wrote this and then saw that it could be the ECU not the BCM!
*****
More likely a BCM fault tbh, if anything.
Actual wiring loom faults are rare.
Remove the BCU from under the drivers seat IIRC and open it up, look carefully for any evidence of water damage and check the connectors for it too.
We must try not to get ahead of ourselves though, sometimes as these problems are simpler than we expect.
Plus, d2 can do odd things, putting the transmission warning light on I think when you have a brake light out.
The faint glow doesn't sound healthy though but I wouldn't suspect the loom personally, not when there's electronics involved...
Cheers
I beg to differ
The BCM, EMU, ECU, ECM call it what ya like it dont control the rear screen heater light
Mr Noisy
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The ENGINE control unit controls the rear screen?!
Will land rover never learn?!?!?
Will land rover never learn?!?!?
Ok. I get the message about shorts. I take it the ECM is the one behind the battery box sierafery. I don't have anything under me drivers seat except the CD autoexchange Mr. Noisy. I will pull the ECM out tomrrow and check for oil. I am not too bad with electrics if I have a diagram in front of me so where do I get a wiring diagram for a 2002 Discovery TD5?
sierrafery
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The ENGINE control unit controls the rear screen?!
Will land rover never learn?!?!?
i wrote there that the ECM(engine ECU named by LR Engine Control Module) has nothing to do with the HRW(heated rear window) .... nor has the BCU(Body Control Unit) with the glowplug lights or Cruise controll...these are managed directly by the ECM...if you dont believe me check the diagram
sierrafery
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Yes
Mr Noisy
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Just have got our wires crossed Bromsgrove!
Tee hee, no pun intended
Tee hee, no pun intended
sierrafery
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Download a RAVE from here and you'll have everything land rover rave technical system
Bromsgrove Defender
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Just have got our wires crossed Bromsgrove!
Tee hee, no pun intended
:hysterically_laughi
Oiliked that! I is easily amused I know
No good avin a short fuse on here Ok guys. I took the ECM or whatever you call it out from behind the battery box and disconnected the black and red terminals. There was some oil on the bottom half of the red terminal which got well cleaned, air pressured and sprayed. The black terminal was clean but got the same any way. All wires anywhere near got cleasned and sprayed and anywhere that looked as though it might be starting to chaff got rubber protections although to be honest nothing appeared to be really chaffing and certainly no wires bared. Anyway the result was engine started first time, glowplug light works again, cruise control switch glow has disappeared, rear screen heater works again and one other thing which I forgot to mention earlier, the temperature overheating warning light has gone out. Everything back to normal. THANKS A LOT TO ALL OF YOU. It's not for me to ask why so I will leave it up to you lot to discuss who was righter than the other as to where the common point for all these things is. Bye bye:bounce:
:bounce:
sierrafery
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there is an earth "rail" with 3 connections near the battery toward the wheelarch which you see it if you remove the cover...make sure all the nuts are well tightened there and give them a spray too and one goes to the BCU, cos maybe you touched it or something jiggling around cos the rear window heater has deffinately nothing to do with the ECM...or there was a "stuck" electronic circuit within the BCU which got reset when you disconnected the battery.
and by the way...if there was oil in the red plug replace the injector loom ASAP or you'll have more trouble
and by the way...if there was oil in the red plug replace the injector loom ASAP or you'll have more trouble
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I think you are dead right sierrafery. All three of those earth wires were slightly loose so they got sprayed and tightened. I replaced the injector loom about 2 years ago when I wa getting a miss fire but will get another one in as a stand by just in case as they are not expencive. Thanks again.
Mr Noisy
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Sweet result
