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I finally got my car going - How did you go Simon. What transpired is as follows - hopefully this might help someone else. Finally got the car going - the amplitude of the crank signal was low and the loom was slightly damaged - although not corroded at all. There must be a threshold at which the ECU rejects the crank signal. Cant find this in any LR documents. Fitted a new crank sensor and after a few revolutions the ECU recalculated piston position and fired up. Regarding the anomally in the relay illustration - it appears that the electrical troubleshooting manual was updated in 11/2000. RL 2 took the place of the previous RL23. The engine managemnt section still shows RL23 feeding the coils - footer date 11/99. The power supply section displays RL2 as feeding the coils - footer date 11/2000. So they updated one section and not the other. The key to this fault was no spark yet the 5V reference circuit from the ECU was active - it was active but needed a good valid crank signal to initiate firing of the coils. This is highlighted by the continual illumination of the amber check engine symbol on the message centre whilst cranking. Thanks to the quality and extensive abilities of the MSV I was able to diagnose the security system and confirm that indeed it was not the culprit. The strange thing was that the car ran beautifully for the 100km drive to my work carpark. When I returned 3 days later I was faced with this problem and no codes to even hint at a CKP issue. I am yet to repair the nick in the loomthe loom - it may be partly responsible if it have some unwanted resistance.

You should havetwo large access ports in the bell housing - you access the flex plate bolts from here. Firstly check these bolts are secure and torqued correctly. Its easy to rotate the engine via the crank pully bolt - especially if you remove a couple of the spark plugs. Then get a cheap USB endoscope via ebay and check the gap between the tip of the sensor and the flywheel. When I refit mine Ill try and get a photo to post. It should be very close without touching. If it is not close enough then the waveform on crank will be poor without enough amplitude to be accepted as a valid sigmal by the ECU - my interpretation. However before you do all this you need to confirm the integrity of the wiring loom for the sensor - is it rubbed/ stretched anywhere. Normally on an engine removal the mechanics stretch this wiring and damage it because it is hidden behind the engine and they dont know its there. It is not until they have stretched the wiring quite a bit do they realise there is still something connected back there. This can be done by checking the resistance at the correct pins of the ECU where the crank sensor feed and earth reside. Im away from my books - cant check the pinouts. The resistance should be about 950 ohm - howver the only real way to check the CKP is via oscilloscope and check the cranking waveform against a good known one - this will also confirm the gap is correct. Good luck

Have you got access to the electrical troubleshooting manual - don't give up yet. You have a cranking engine but no firing - that's better than no crank. Have you read the fuel pressure. There are two 3 pin plugs on each coil pack - ensure that battery voltage exists at pin 2 of connector 52 and 156 - the BeCM grants this via grounding relay 23. BTW your fuse box lid may not show a relay 23 - maybe someone else can explain which is the correct relay - anyhow the important point is getting power at the pins of the coil packs Insert an inline spark tester - check the quality of the spark. Its is very strong and will jump at large gap. Carefully inspect all of you wiring loom - looking for rubbed insulation. Any rubber insulation with corrosion will have a large impact on sensor input waveform Lastly remove the crank position sensor - check it is not damaged at the tip and that it is about 940 ohms between pins 1 and 2. Aftermarket ones are pretty cheap - buy a replacement and fit it. Be careful and check if there is a spacer or not. Don't worry you will get there eventually. Ignition coils relay.pdf

Hi SImon, In the same situation - car stuck in a carpark 80km away. If you have the Motronic P38 then the coil packs do not need to be bolted down for an earth - earth path to collapse the primary is via ECU. Which model do you have and what have you done so far - we can compare notes. Peter - Australia