Discovery 2 Crank no start, only 6c permanent voltage supply dtc

[jassoyer]

Hello, hoping someone can assist me in the right direction please, mechanic also lost the original crank sensor, does it use a spacer on the manual v8 4.0?

ALso on the crank sensor wiring I have a ground and both other wires supply 2.4 vault, should the one not supply 12v 0r 5 and the other a signal wire?

Thank you in advance.

[Tins]

Simple things first. Have you checked the crash switch? Inertia switch on the firewall, might need resetting.

[jassoyer]

Hello and thank you for the prompt reply and yes i have pressed it multiple times lol.

[sierrafery]

Hello, hoping someone can assist me in the right direction please, mechanic also lost the original crank sensor, does it use a spacer on the manual v8 4.0?

ALso on the crank sensor wiring I have a ground and both other wires supply 2.4 vault, should the one not supply 12v 0r 5 and the other a signal wire?

Thank you in advance.
Hi there is not supposed to be any supply for the crank sensor, that 2.4V might be capacitive if it's not an ECU fault, i attach you the description rather than explaining myself but you need a compatible scantool to diagnose this and watch rpm which must be above 250 while cranking for te engine to start and if it was the sensor a specific fault code should be present

[jassoyer]

Thank you very much, that is the part confusing me.... only have a single fault code -6c permanent volage.... drive cycle A. REason I am investigating the crank sensor and voltages/signal to each wire on the cps is to establish if the cps is working as I see no rpm on tacho or Autel elite or Launch x431 V+.

[sierrafery]

only have a single fault code -6c permanent volage..... Which P code is associated to that?

[jassoyer]

Will get oem tool to test and confirm as I can only get the 6c code with my two high end tools.

[jassoyer]

Greetings, sorry for the delay, error code is p109, changed the crank sensor as a new replacement arrived, still now no injector pulse or spark, but zero fault codes now to work off..... No rpm still.

Get a landie they said.... lol :) gonna be something sillyI feel, not clued up enough yet with landies to be honest... Any further suggestions would be appreciated?

[sierrafery]

The OBD code should have 4 digits after the P so that 109 is not clear enough, if it was 0109 it was about MAP. As long as no rpm reading the sparks and injectors are inhibited by the ECU... swap the two big relays at the bottom of the interior fusebox(R3-R4) see if it helps and if not remove the lower one R4, bridge the perpendicular cavities(where the contact goes) with a wire and see if you get spark then...if not measure if you get 12V across the parallel cavities(where the coil goes) when you turn ignition on...allso check fuse F14

if no joy with the above check fuse F13 engine ebay and swap relays R9(main) with R8 there

[jassoyer]

Hello again, got a chance again to have a look at her, checked all relays and fuses and they appear okay, tested with power probe, putt he wire bridge to relay 4 like you suggested |-- ports of the relay, still no spark, not sure of which = ones you refer to as I o not get 12v on the two on the same relay 4. Just checking I am understanding your info correctly? Thank you again, really appreciate your help.

[sierrafery]

for me 30 - 87 are perpendicular(contact) and 85 - 86 parallel(coil) if on R4 INTERIOR FUSEBOX you dont have power across 85 - 86 while you crank it that's the reason to not have sparks as that relay feeds the ignition coils and this relay is completely managed by the ECU which if misses the crank signal(no rpm reading) it inhibits the sparks and injectors... a complex electrical trouboeshooing is needed done by somebody know how it works and can follow the diagram to see if the signal doesnt leave the ECU or it does but not reaching the relay and why the rpm is not shown, i can't help more from distance with this fault sorry... the ECU is quite suspect at this point but nanocom or similar is needed to rule it out

in a nutshell, you must get about 250 rpm reading with scanner while cranking otherwise it will never start but i can't tell how to achieve that without being there myself

[jassoyer]

Good morning and thank you very much for all the guidance Sieraferry, I opened the ecu to have a closer look and it has zero signs of water damage, dry joints etc, next thing I am going to look at is the connectors on the loom, are a couple that get water ingress. And what appears to be the main culprit the fuse box(cabin) with the internal relays. Also if i may ask, there are two orange coloured 4 pin connectors on each side of the head close to the firewall, do these go anywhere?

[sierrafery]

G'day... i can't help with those connectors but if you have a compatible scanner as we know you get no rpm reading watch all the other general inputs (battery voltage, coolant temp, air temp, manifold pressure, air flow, etc) which should be as for a cold start then watch the battery voltage while cranking...if it drops below 10V the ECU can't do it's job.... the engine can crank well even if the voltage drops to 6V while the ECU needs good power to work.

BTW if you don't get power across the ignition relay(R4) coil you shoud replace the fusebox with known good one to rule it out before chasing other issues

[jassoyer]

Just to repeat, I really appreciate all your time effort assisting me, and I am not getting power across R4 relay. :)

[sierrafery]

Just to repeat, I really appreciate all your time effort assisting me, and I am not getting power across R4 relay. :)
Then better rule out the fusebox before you go further

[jassoyer]

Hello, sorry for the long delay, took a while to get hold of an interior fusebox and then another... As my problem remains, are there any additional connectors maybe that I should look for to try resolve this, really dont want to send her to the breakers but its starting to really frustrate me now :(

[sierrafery]

I feel for you...after the fusebox swap do you get voltage on the ignition relay? or the main issue persist as still no spark?

[jassoyer]

Thank you for responding yet again :) Yes I now how power across relay R4 (Ignition). I can see on the scope I have AC signal when cranking on the crank sensor directly. No sure what to look at next... TAcho and diagnostic still show rpm and no fault codes.... Any more smart directions of attacking the problem are appreciated Sierra? So still the primary issue with no spark.

[sierrafery]

I'm running out of ideas as i'm not the best when it comes to petrol engine behaviour once the suspected electrics were ruled out...as long as it gets fuel alnd spark it should fire IMO but i know that the V8's can be hard to start if the MAF sensor is dead, can you see it's live input?... start it with spray maybe once started it'll keep running then you can watch all the live inputs or once it's running the ECU might identify some issue and throw a fault code

[jassoyer]

Problem is that it receives zero spark, have power going o the coils, but get zero rpm on the tacho. Which I believe is the cause of my issue.

[shack]

Problem is that it receives zero spark, have power going o the coils, but get zero rpm on the tacho. Which I believe is the cause of my issue.So no RPM reported on scan tool?

So what things ARE reporting correctly? There should be lots of things.

[Tins]

Smarter folk than me are commenting here, but it seems to me that if the oily bits are going round and round like they should and you have power to the rest then you're left with the CPS. Sure, you've changed it but.... Just because it's new doesn't mean it's good. Also, there's the reluctor ring, but I dunno the failure rate of those.

[jassoyer]

Thank you for you reply, heaps of things... I am using an Autel Elite and Launch x-431 V+ even used a friends hawkeye,... Zero display on the Tacho or engine speed via Diagnostics. Not sure what to look at next.... about 600km from the nearest landie specializing workshop and not too inspired after chatting to some....
Also it has a Unichip fitted, which I neglected to mention before.

[jassoyer]

Thank you for the assist Tins, I have bought a second new CPS and my issue remains, any way to simulate the reluctor ring?

[AK83]

I can think of 3 things so far not commented on that could be easy checkups for you.

Weird that you get no spark, so (according to RAVE .. manual) there are spacers of the CKP(crank sensor), smaller for manual, larger for auto boxes. It also says there are two spacers, in the repairs section.
I haven't pulled a V8 apart(much) and have zero experience back there, but if any part of these spacers are not fitted, just in case some other mechanic has tried to repair the vehicle before.

So, important question is, what do you know of the history? have you just got it and want to get it going, have you had it all it's life and it suddenly died. Important info so that you know, someone else hasn't botched up a repair and used wrong parts .. or something. Seen this so many times, its the most frustrating part of getting an old landrover.

Anyhow, second possibility, I didn't see any mention of immobilisation. Immobilised, no way you will start engine. red light on dash can be configured to not flash, so don't just rely on this telltale sign. Again, this comes back to knowing history of the vehicle. I haven't connected my Autel to the V8 to see how accurate it's OBD data is compared to the nanocom, but I did used to use an obd dongle and Torque app, and generic obd can give 'different' codes compared to nanocom in some situations.
Autel could be better than a $10 generic dongle ... I don't know. But nanocom will tell you if vehicle is immobilised. If you're lucky enough to have the EKA code still with the vehicle, this could be an option to try just to be sure.

Anyhow, #3 possible issue not commented on is the cam position sensor. the reason for this possibility would be that, it won't show any code if it's a problem, as it only shows code if engine revs above 500rpm .. so you won't know if it's short or open until engine starts.
cam sensor less likely problem as if it's dead, the ECU just uses default values .. I guess maybe just rough running or something ... again, no experience just guess. But it can't hurt to check for voltage there too.

SF has already mentioned fuse 14 in the passenger fuse box, we assume you checked and double checked so power to coils. but have you tested coils and or leads too? Can you access spares to try out?

my feeling is most likely immobilised tho. if you can get friends Hawkeye again, and it can check this situation, would save you a lot of grief.

[jassoyer]

Good Morning Arthur,

Apologies for the very late reply, Big thank you for your insightful reply, there are no immo issues with the hawk eye tool either, or Autel/launch. All three units only detect missing rpm on cranking, going to check compression as I read it is maybe a timing chain issue as she swings very easily. I have zero fault codes, everything works, security light goes off, fob works, alarm works, can manual test inertia switch, though both back doors wont open- think a mechanical issue there.

I received only two spacers with my crank sensors, a big one that takes almost the full front on the CPS with I understand is for the Auto's. The smaller spacers only covers half of the protruding part of the CPS sensor.

I own a workshop in a small town about 450 km nearest a LR hopefully professional. And have worked on a couple landies, but more the diesels for small things and services etc. This vehicle was at 4 or 5 workshops before coming to me... Owner gave up on it and I assisted him with a mk3 Audi TT engine etc to assist him, as i truly felt sorry for the man... He replaced the complete lockset also(Ecu Bcm and key).

I had always wanted a landie D2 to be precise, just love the look from when I was a young boy lol.... And the sound of that v8.... Music even though slow. So yes looking like a lemon... But it is in such good condition still, dont really want to give up on it, have gotten 2 new CPS and 2 internal fuseboxes. The original ecm has a unichip fittted, I sold the original lockset on the previous owners behalf has the Mechanics had raped him to the tune of 42k and his vehicle was still unable to start, did not see any fault with this side, suspected the IDM (interior fuse box). The crank sensor was missing when it came to me with no spacers to be found. Have seen there is a another spacer online which is basically half that of the half spacer. Do i need to try get that half spacer?

Regards,
Jasson