FZJ80 won't start - help! (2 Viewers)

[Paul D63]

Sorry guys - real nice of you all to carry on without me, thanks for all the responses so far.

I really thought I was onto something today, but hopes have been dashed I'm afraid and I'm now getting ready to start pulling my hair out! But I really need you guys to stick with me in my hour of need if at all possible.

I was lying awake last night thinking about all the things we'd discussed, and I had an inspiration (or at least, it seemed like one at the time): I thought that, what if I had a new key made to the same mechanical spec as mine, but without a chip in it, but it would operate the ignition lock mechanically? My logic was that this wouldn't be expensive, and if I could produce the same symptoms of starting and cutting out with a key that's known to have no chip, then that proves that the immobiliser will indeed allow the engine to run for a few seconds. If, on the other hand, I couldn't make it run at all with the chipless key, then maybe this debunks the faulty key theory.

So, today, I went back to the local locksmith to see if he had suitable non-chip key blanks. He did, and I got him to make me a key. Came back, tried it in the ignition, and got exactly the result I was expecting - the truck behaved exactly as before - start, run & cut out after a few seconds. Aha! I thought - this, combined with the other evidence (the code 99, the fact that no one has been able to find any discernible signal from my original key) proves that it is indeed simply down to the fact that my original key has died. There was another guy working in the locksmith's today, and he sounded fairly knowledgeable, and told me that if I took him my immobiliser ECU, he would be able to read the chip and program a new transponder key to work in conjunction with it and end my woes.

So, after finding the immobiliser ECU, just where Dave 2000 said it would be - only, for me, that's the driver's side (RHD, but I hadn't seen Dave's post at that time, so was lucky to find it), I duly removed it and took it to the locksmith. Wasn't expecting to get a call from them until at least Monday, but was surprised to get a call a couple of hours ago saying it was done and I could pick it up along with a new transponder key programmed to suit.

Great news I thought to myself... but you all know where this is going don't you? Yep, sure enough - plugged everything back together, connected the battery, put my shiny new transponder key in, turned it, and... exactly the same as before! Starts, runs for a few seconds, cuts. Tried a few times, same result each time. To say I'm p*ssed off would be an understatement. £70 spent, no closer to a solution. But it's not the money, it's just the sheer disappointment of having that expectation that it was going to burst into life, only to hear it cut out just as before.

So I'm back to square one. Where the hell do I go from here?

To clarify a few points raised since my last post: Dave 2000 - contacts on the immobiliser ECU are squeaky clean, no signs of anything that would cause a problem. The locksmith said the ECU checks out as far as he can tell, but I don't know his level of expertise. Yes, it does behave inconsistently - doesn't start every time, but when it does, it's the same thing each time. For example, there was a whole day earlier in the week where it barely started at all, despite many attempts. But the day before, it had started maybe 30 times in succession, barely failing to start at all until eventually, it stopped firing and that was it for the rest of that day.

sbman - my immobiliser ecu is just like the yellow one in your pictures - appears identical in fact. You are a font of information on these things, and it was as a result of our discussion that I came up with the idea to try a known non-transponder key to test for the same results and therefore confirm our immobiliser theory. I thought the theory that my original key had died was sound...

Cruiser Dan - I am indebted to you for trying the same tests on yours, it provides as close to a like-for-like comparison as we're likely to get with this system not being in use on U.S. models. However, from what you've said, it sounds like mine is behaving pretty much the same as yours, so I'm left scratching my head. I too, have tried starting mine with the MAF unplugged again today (using the new transponder key), and it sounds similar to what you're getting: no MAF and mine starts, runs for maybe a second, dies. Doesn't sound quite as clean as when the MAF is plugged in. So, MAF plugged back in, starts and runs, but this time for maybe three or four seconds, and in any case, much longer than with no MAF, then dies. As mentioned previously, I can get it to run for maybe another couple of seconds if I have an assistant turn the key the instant I reconnect the battery after a period of disconnection. The behaviour does not appear to have changed in any way whatsoever with the new transponder key, as I've just done all this with the new key.

What the hell now guys?

 

[cruiserdan]

Since our example, with the Immobilizer ECU disconnected, acts as yours does with everything hooked up, this suggests that there may be a problem with your ECU or perhaps the transponder coil, or some other input into the ECU that is interrupted with the ECU disconnected.

When I disconnect the ECU I interrupt everything. If any one of those many wires is corrupted it may have the same affect. Isolating it will be a challenge.

 

[cruiserdan]

Another thought:

If your locksmith was indeed successful in taking your ECU and mating a key to it, this suggests the ECU is functioning. In turn this suggests that there is some input the ECU needs that it is not getting.

 

[Paul D63]

Another thought:

If your locksmith was indeed successful in taking your ECU and mating a key to it, this suggests the ECU is functioning. In turn this suggests that there is some input the ECU needs that it is not getting.

Well, that's what he tells me, so I can only assume he knows what he's doing? That's the frustrating thing - there's just no way to know, as sbman pointed out: these early versions don't get the light to let you know if it's recognised the key, so you're just left guessing.

What we can be pretty sure of I guess is that my original key was dud, seeing as no one managed to retrieve any signal from it. But that leaves the question: what are the chances that I've got a bad key AND, at the same time, another immobiliser related fault? It seems very unlikely to me, especially when you consider (as I understand things) that a bad key couldn't cause damage to the immobiliser ECU, and vice-versa. This means we have to believe that as well as a dead transponder key, I've somehow simultaneously developed some other fault within the immobiliser system. Seems like too much of a coincidence to me - I don't like coincidence theories and I'm not buying it! However, under the circumstances, it looks like I may have to hypothetically for now, at least!

Now that I've had a chance to calm down after my initial disappointment, and giving it some thought, something has occurred to me: this is a reeeeal long-shot, but I'm gonna put it out there for consideration as I'm getting desperate! So, here goes: The new key I have is a generic one, not a Toyota one, and from looking at it, it appears that the transponder is fitted in the top part of the head of the key, that is, furthest away from the ignition cylinder. Now, from what I read on an aforementioned thread about a Danish guy with the same transponder key as mine, it seems that in those keys, the transponder may be in the base of the plastic head - that is, closest to the cylinder barrel, and therefore closer to the coil that reads the chip. As I've also learned that these keys apparently operate on a very weak signal, is it possible that the chip in the new key is simply too far away for the coil to read it? Yeah, I know, but I'm grabbing at straws now!

I suppose it's a theory I can test easily enough, as it looks like the new chip could be removed from the key, so maybe I can remove it and tape it closer to the coil to test the idea? Worth a try?

 

[cruiserdan]

I suppose it is possible that the new chip isn't close enough. What you may try, that is not destructive, would be to put the original key in the lock and place the head of the new key as close to the ring as possible and start it.

 

[sbman]

Is it still throwing the code 99 with the newly programmed key?

 

[Paul D63]

Is it still throwing the code 99 with the newly programmed key?

I wondered that myself - something I'll check tomorrow in the daylight.

 

[sbman]

I would really like to see the FSM troubleshooting procedures for the immobilizer. I've searched everywhere and can't find any source for the FSM for purchase or download at all. Only stuff for U.S. market trucks.

 

[ppc]

Did the locksmith have both your ECU and coil/transponder. If you didn't provide that portion of the entire system then the coil circuit or the wiring harness from key to immobilizer ecu or immobilizer ecu to main engine ecu/ecu still could be the issue. Intermittent issues in my experience are more often wiring issues or connections.

 

[Dave 2000]

First can we get the reason for the cutting out i.e. is it lack of fuel or spark or both? I would open the air filter lid and with an assistant cranking the engine I would spray small amounts of ether into the air intake, if the engine stays running it is a fuel problem, if not then it is a electrical issue.

Lets get back to basics, I have joined this thread a little late in the day so sorry if I repeat something somebody else has suggested.

I gather the car stood for quite awhile, do we know how long ago? Was it parked up because of a problem in the first place. Has the fuel been replaced as the loss of aromatics can make it less volatile. Is the fuel intake to the pump blocked (gummy fuel), has a kid dropped a Smarties buttons tube lid in the tank? Yes I am serious.

regards

Dave

 

[Paul D63]

I would also really like to see the troubleshooting procedure for the immobiliser, but also haven't been able to find any info relating to it. sbman - if you can't find it, don't suppose there's much hope for me finding it either. I have posted on a UK based Land Cruiser forum, but I just don't think we have the numbers here that you have over there, so probably nothing like the knowledge base either. I also think that, as a nation we're less inclined to work on own vehicles nowadays, so probably not that many 'getting their hands dirty' and trying to solve such issues. Whereas, over there, it would appear there's still a large number of you doing you own repairs & maintenance. Or maybe it's simply a factor of the sheer numbers, I dunno - but there must be five times more people over there than here.

Anyway, back to my problem. I tested my latest theory as mentioned above, and real long shot it proved to be, as I suspected. But holding the new key head as close as possible to the ring on the cylinder whilst cranking with the non-chip key I had made produced no difference. I tried holding the new transponder key in different positions close to the ring, but all produced the same results as before. And I can now confirm that code 99 is still coming up using the new transponder key. In fact, having cleared the codes to try again, I've noted that it comes up even before I've tried cranking the engine for the first time after battery re-connect. But I suppose the fact that I have to insert the key and switch on ignition to read the codes means the immobiliser has already had a chance to reject it and store the code. Does that sound about right?

Phil - the locksmith had just the old key and the immobiliser ECU. He didn't get the coil amplifier, simply because I'm not sure he would have been able to do anything with it. The wires coming out of the coil amplifier go straight into a multi-plug, and in turn, those wires disappear into the loom and reappear, I assume, at the plug going into the immobiliser ECU. So without that section of loom, I don't think it's possible to connect the amplifier to the ECU off the vehicle to allow for a full test of the complete assembly. Unless, of course, you had some sort of test lead to join the two together, but I don't see a regular locksmith having that level of equipment, and probably not the knowledge to do so either. By the way, I can confirm all of the aforementioned connector plugs are spotlessly clean with no signs of corrosion.

So that's it guys - I'm stumped. I hate being defeated by a vehicle fault, but it's looking like I may have to throw the towel in on this one, I simply don't know where I go from here. Maybe I've got it all wrong and it's actually nothing to do with the immobiliser, but until I can get it to stop showing code 99, I can't rule it out can I? And as Dan's similarly equipped vehicle displays the same symptoms as mine when he unplugs his immobiliser box, then it does seem to suggest that I do have an immobiliser issue. But without access to any meaningful info on how to test or diagnose faults in the immobiliser circuit, then I'm basically screwed now. Game over?

 

[Paul D63]

Sorry Dave - you posted while I was typing the above. To save you reading through what is now a long thread (thanks to all who've tried to help so far), I'll give a brief synopsis of what's happened so far.

Initially didn't think it was immobiliser related, so have done the following checks:

1) Fuel pump is running, even after engine cuts (couple of seconds, as normal). Pump circuit wiring has been bypassed with a direct battery voltage feed to the pump, no improvement. With pump circuit back to normal, pump pressure tested at 80+ psi absolute, but haven't as yet tested in-situ system pressure. Fuel under pressure is present in the rail.

2) MAF tested as per FSM - all within spec. Gave 0.6V static, 1.3V cranking (so air at cranking speed flowing through it) & around 2V when it fired and idled briefly when the voltmeter was still connected.

3) Fuel pump resistor tested - within spec, as far as I could tell allowing for different ambient temp at time of test compared to that quoted in FSM. But surely any fault there ruled out by operations carried out in (1) above?

4) Main EFI relay clicks if unplugged & plugged back in with ign on. No blown or corroded fuses/terminals that I've found so far. Verified good earth to engine. Strangely, FSM says to expect continuity across terminals 1 & 3 of EFI relay - I got 68 ohms. Not sure if that constitutes continuity, but nevertheless, when 12V is applied to 1 & 3, I get continuity across 2 & 4, so it is switching on as expected.

5) IAC in-situ resistance tests all within spec - 20 ohms across all terminal pairs @ ambient temp. of around 7 degrees (C). Can't get the screws out, so haven't been able to test it off the vehicle. But don't think a bad IAC would prevent it running completely, and pretty sure it wouldn't give my symptoms?

6) Spark present. Tested at cranking then removed one lead, inserted a plug and tested when running - spark is still present even after engine cuts, just for that second or so it takes the engine to stop rotating after it cuts. So it seems ignition is not my problem. Did fire when starting fluid sprayed into throttle body, although it wouldn't actually run.

Before the immobiliser became my prime suspect, the results of all the above led me to believe my injectors were not being switched on. Let's face it, if there's fuel under pressure in the rail, a healthy engine and a correctly timed spark, then the only thing to prevent it at least trying to run is if that fuel isn't being allowed to pass the injectors? Anything else is incidental - if there's fuel, compression and a spark, then I should get something. A faulty IAC, MAF, TPS, pressure reg or whatever else would give me running faults, but I'm not sure any of them would give me absolutely nothing at all, which is what I get on those occasions when it doesn't start immediately, run perfectly and then cut out after a couple of seconds. Then when sbman said he thought the immobiliser cuts the EFI, specifically the injector feed, then that made sense for it to be the immobiliser at fault, as by then I had convinced myself that the fault lay with my injectors not being switched on.

We also have to consider that Cruiserdan's similarly equipped truck gives the same symptoms as mine when he tries starting it with his immobiliser unplugged.

And that brings us to here. And I'm stumped!

 

[cruiserdan]

Have you tried disconnecting the battery to let everything re-set? That too is a long shot but doing that will eliminate one more variable. That should clear the stored code and you could then determine if the code returns or simply never left.

If the code returns logic then dictates there is indeed a fault. Possible ECU, key, sensor ring, mouse-chewed wire, power source, adnuseam.
You really need to dig up a manual someplace.

 

[sbman]

I think that at this point you either have to find a proper factory manual or start throwing parts at it. Even parts may not help if there's some particular procedure that has to be done with the immobiliser. If the amplifier and ring could be had locally from a breakers that might be the easiest parts to try first. Verifying that the injectors stop firing could be useful info as well.

 

[Paul D63]

Yes, just to clarify - I've been disconnecting the battery and leaving it disconnected every night for the last few days, so plenty long enough I would have thought for anything to reset, codes to clear, etc. My Haynes manual simply states disconnecting the battery at all is enough to clear codes, and I seem to remember that's been my experience in the past. However, I've always been sure to leave it disconnected for at least a few minutes when I've simply wanted to clear the codes to check for their reappearance.

 

[Paul D63]

I did ask the locksmith if I needed to follow any special procedure when refitting the immobiliser ECU or using the new key, and all he said was just to reconnect all the components BEFORE reconnecting the battery, which I did, and then it would be ready to go. He reckons there's no procedure I need to follow to make the new key 'talk' to the vehicle. If he makes these keys as part of his job, then I'd expect him to know if I needed to do something else. Maybe I'm over-estimating his knowledge or abilities? But there's no way I can know.

 

[cruiserdan]

About power connection. When I did the test where I disconnected the immobilizer ECU, tried to start it and then reconnected it, I did not disconnect the battery and everything worked. In hindsight perhaps I should have disconnected it. Fortunately I didn't wreck anything.

 

[flintknapper]

4) Main EFI relay clicks if unplugged & plugged back in with ign on. No blown or corroded fuses/terminals that I've found so far. Verified good earth to engine. Strangely, FSM says to expect continuity across terminals 1 & 3 of EFI relay - I got 68 ohms. Not sure if that constitutes continuity, but nevertheless, when 12V is applied to 1 & 3, I get continuity across 2 & 4, so it is switching on as expected.

A common misnomer (not necessarily the case here) is that folks believe when power is applied to a relay and it 'clicks' that is it good.

Of course what they are hearing is the electromagnetic portion of the relay 'switching', BUT that means NOTHING other than it switched just enough to make a sound. It doesn't account for corroded or pitted contacts...or high resistance through the remaining circuit. A resistance test should always be done to confirm a relay is actually 'good'.

Sometimes another relay nearby (of the same type) can be swapped out to see if that corrects the issue at hand. Most relays are not very expensive....so simply replacing one can sometimes be the easiest thing to do, especially if a person (not you) doesn't have the equipment or know-how to test one. Having a 'spare' EFI relay is not a bad thing if the original turns out to be good.

I'm not yet sold on the idea that your issue is immobilizer related. But I can certainly understand your frustration at this point.

 

[Paul D63]

I'm not yet sold on the idea that your issue is immobilizer related. But I can certainly understand your frustration at this point.

Summed it up in one line! I've sort of convinced myself it is immobiliser related, but that's the frustrating thing, because I can't be sure. And until I can reach a point where I can prevent code 99 from appearing every time I wipe the codes, how can I move on to looking at other areas with any confidence when the OBD keeps throwing up code 99?

If that code had now vanished since the arrival of the new key, I'd be the first to hold my hands up and say 'OK, it wasn't the immobiliser (or, at least, wasn't only that), so where do I look now?' But the reappearance of code 99 every time is just eating away at my brain. Surely it must be detecting some problem in the immobiliser to keep throwing that code?

I did think along the same lines as sbman and perhaps see if I can find another coil amplifier assembly from a breaker, but it's really just fumbling around in the dark and hoping I fall over the problem part by pure luck isn't it? And pure luck seems to have packed up and left town at the moment!

I did think about simply wiring up a standard 4-pin relay to replace the EFI relay, but haven't convinced myself it's worth trying at this stage. However, as a relay is simply a switch that's fired electrically, then I could adapt any standard relay with the appropriate current rating just to rule this out. But as my existing one shows perfect continuity between the 'load' terminals when the 'switch' terminals are powered, then I have to say it looks to be working normally. Although I do understand that good continuity doesn't necessarily mean it can handle the load.

 

[Paul D63]

Dave 2000: I should add a couple more answers to questions you posed:

Vehicle been off the road around three years perhaps, but only maybe a little over a year since it was last running fine, when I started it and moved it to where it currently sits. Fuel is fresh - put some in earlier in the week, but it was displaying exactly the same symptoms before I added the fresh fuel, and things didn't improve with fresh fuel. Before you ask: there was almost no fuel in it before I added the fresh stuff, so no, I don't think the fresh stuff has simply been diluted by a load of stale fuel. What little was already in the tank was only put in when I moved it to its current spot, so it's not much more than a year old anyway.

No one could have had access to the tank to drop anything in there - it's been locked up all the time it's been parked, and UK spec Cruisers have a locking fuel flap that locks whenever the doors are locked. And there's no sign of it having been forced open, and I've never found it open when it shouldn't have been either.

There were multiple reasons for taking it off the road, but mainly cosmetic - it needs some bodywork and paint remedy. However, there was one engine related issue that also contributed to my reasons for parking it up: It had started throwing up a code related to knock sensor issues. When it threw this code, CEL would come on and it appeared to go into 'limp mode' (lack of power) as I would call it - a safe mode I guess where I imagine it retards the timing significantly due to receiving no signal from the knock sensor. This fault will still be present, but I haven't had the code for it since, simply because it generally only picked it up when the engine was under load, vehicle being driven, and I haven't been able to get it to run long enough for that. I'm sure that code will reappear once I have it running, but I'm also pretty sure it can't be related to my current situation. Worst case scenario for that code is the 'limp mode' but it always started and ran fine up to the point it picked it up.