Rav4.1 Help Needed Please

[Grizzly Adams]

I hope someone can help me. I spent all last night trawling through old threads hoping to find an answer but only a few clues so far.

Rav4 1997 3 door petrol auto GX.

It's my wifes car and we have had it nearly 6 years, and apart from an appetite for tyres at the front, I can honestly say it has been as good as gold. Drove wife to Heathrow saturday before last, dropped her off, drove home, parked car etc etc.

Decided to use the Rav for a change on thursday and it wouldn't start. Turned over fine, but ran the Battery down rather too quickly, so, as the old Battery was about 4 years old, bought a new one at the weekend and fitted it. Turned over great but wouldn't fire. Checked plugs, sparks evident. Changed plugs for good measure, no change. Cracked the banjo bolt on the fuel filter, petrol spraying when key turned.

Well that's as far as common man can go, so after much soul searching, called the RAC. Nice man (very nice man) came straight out, and performed all the same checks as I had done, but metered the injectors and found 12v one side, but open circuit the other.

RAC man towed me to the local garage, he said his diagnostic kit wouldn't fit a vehicle of this age, and we left it for them to have a look at. I called just before home time tonight and they say that the ecu has no registered faults, and that they suspect the fuel pump, despite the RAC man telling them it's the feeds to the injectors. This has done my confidence no good at all, and I am now expecting them to change everything that is working fine, and end up with a huge bill.

I keep coming back to the circumstances surrounding the failure. One day working, 5 days later not. The only thing that has been used is the alarm. It's the black fob with 2 buttons one above the other and the Toyota logo moulded onto it. We only have 1 key, so it's the same one as always. I have tried pressing both buttons to re-synch the fob, but it hasn't made any difference. Does the key have a chip in it?

I really feel like towing the car back and trying to sort it myself, but with no wiring diagrams it would be a long job. If it's got sparks, and fuel, can it still be immobilised?

Thanks in advance,

Griz

[bothwell_buyer]

With the change of Battery I would guess first at the immobiliser has kicked in. Everything turns and sounds ok but just doesn't fire?

If thats the case, then I'd get the immobiliser bypassed and try that first. These things were installed after manufacture and I've found the way they are wired up varies a bit. Normally 2 circuits are broken by the alarm which you can trace by tracing back the black wires from the alarm/immobiliser ecu unit. If you aren't sure, get an auto-electrician to remove the immobiliser - I'm fairly sure that would do the trick. The systems from back then are ancient and the electronics was probably designed almost 30 years ago.My number 2 RAV has the type of immobilser you describe but we disabled the immobilsier bit - the rest of the alrm misbehaves but doesn't affect the car....but keeps the remote locking working. New systems are available which are more relaible and can be fitted to yours.

[Grizzly Adams]

Bothy, Yes the Battery being renewed may have had an effect, but it wasn't running before, hence the suspected need for a new Battery. I agree that the obvious next step is to immobilise the immobiliser, it woud appear to be the only way to move forward.

Thanks for your help,

Griz

[HEMI]

have you checked for a spark at the plugs???

[sc15]

My sister's 94 Rav had the same problem, working fine one minute then turned over fine but wouldn't start. I disabled the immobiliser and all was well again.

The alarm/immobiliser box is behind the glove box and as far as I remember there are four black wires which run from it across the car to under the dash and into the footwell on the right. These wires need to be cut where they join the Toyota harness and the break in the harness wire rejoined. The black wires can then be taped up out of the way. Hope that helps.

[bothwell_buyer]

as these things seem to be wired randomly, then logical checking can be a waste of time. On the early 4.1s, a lot of the switching was done on the earth side rather than the live side - and I guess the immobiliser may well have intervened on the earth side of the ecu - sometimes this is a logical way forward as it prevents hot-wiring.

[Grizzly Adams]

Thanks guys. The alarm is in the engine bay on the drivers side. The car is in the Noddy Garage at the moment. Assuming I can extract it from them I will get to work at the weekend. I have done this sort of thing many years ago, and found it best to cut the wire to the siren before doing anything. I am now totally convinced the alarm is the problem.

Thanks again

Griz

[sc15]

Thanks guys. The alarm is in the engine bay on the drivers side. The car is in the Noddy Garage at the moment. Assuming I can extract it from them I will get to work at the weekend. I have done this sort of thing many years ago, and found it best to cut the wire to the siren before doing anything. I am now totally convinced the alarm is the problem.

Thanks again

Griz

On our car, the box under the bonnet is just the alarm siren, the alarm/immobiliser ECU is under the left side of the dash behind the glove box.

[bothwell_buyer]

Thanks guys. The alarm is in the engine bay on the drivers side. The car is in the Noddy Garage at the moment. Assuming I can extract it from them I will get to work at the weekend. I have done this sort of thing many years ago, and found it best to cut the wire to the siren before doing anything. I am now totally convinced the alarm is the problem.

Thanks again

Griz

On our car, the box under the bonnet is just the alarm siren, the alarm/immobiliser ECU is under the left side of the dash behind the glove box.

ye - the siren and gubbins is perched on the bulkhead under the bonnet. However the ecu is tied with a plastic tie/s to the support brackets below the radio and underneath the dash normally. You'll find it easily enough from the number of black wires leading to it. I removed the glovebox and lower panels and centre panels and kick bits - easy enough.

[Grizzly Adams]

Thanks chaps, really feel I'm getting somewhere now.

Have told the garage NOT to do any more work on it and I will take it away. Got a call from them 15 minutes later to say that the cam belt is very loose and it may have jumped a tooth.

So they have diagnosed faulty fuel pump, now loose cambelt, despite having a written report from the RAC stating that there is no switching on the earth side of the injectors.

I hate to be distrusting and doubting, but the sooner I can get the car out of there the happier I will be. So far the garage would have spent 4-500 pounds and not have found the fault.

And the info on the alarm ecu will be invaluable, thanks.

Griz

[bothwell_buyer]

Thanks chaps, really feel I'm getting somewhere now.

Have told the garage NOT to do any more work on it and I will take it away. Got a call from them 15 minutes later to say that the cam belt is very loose and it may have jumped a tooth.

So they have diagnosed faulty fuel pump, now loose cambelt, despite having a written report from the RAC stating that there is no switching on the earth side of the injectors.

I hate to be distrusting and doubting, but the sooner I can get the car out of there the happier I will be. So far the garage would have spent 4-500 pounds and not have found the fault.

And the info on the alarm ecu will be invaluable, thanks.

Griz

jumped a tooth? sounds like a job for the dentist. Claim it on the NHS.

[Davrav]

Thanks chaps, really feel I'm getting somewhere now.

Have told the garage NOT to do any more work on it and I will take it away. Got a call from them 15 minutes later to say that the cam belt is very loose and it may have jumped a tooth.

So they have diagnosed faulty fuel pump, now loose cambelt, despite having a written report from the RAC stating that there is no switching on the earth side of the injectors.

I hate to be distrusting and doubting, but the sooner I can get the car out of there the happier I will be. So far the garage would have spent 4-500 pounds and not have found the fault.

And the info on the alarm ecu will be invaluable, thanks.

Griz

jumped a tooth? sounds like a job for the dentist. Claim it on the NHS.

You can find an NHS dentist :o

I'm moving to Scotland.

Actually my dentist is a Scot :) She obviously knows where the money is to be made ;)

[Grizzly Adams]

Have stripped out the alarm ecu and it plugs onto the loom with a proper multi plug so no chance of finding splices. Also the wires from the loom don't particularly coincide so I have go an alarm fitter friend of mine to come tomorrow to remove the immobiliser side of things.

If that doesn't work is it fair to assume I need a new ecu?

griz

[bothwell_buyer]

Have stripped out the alarm ecu and it plugs onto the loom with a proper multi plug so no chance of finding splices. Also the wires from the loom don't particularly coincide so I have go an alarm fitter friend of mine to come tomorrow to remove the immobiliser side of things.

If that doesn't work is it fair to assume I need a new ecu?

griz

you'd be surprised at the amount of wires and spare plugs you get left with after removing the immobiliser ecu.... including I think at least 1 multi plug. There used to be only 4 wires - ie 2 circuits that were interupted so its 2 wires going and 2 coming from the split. They sometimes were taped onto the harness going across the underneath of the dash.

be very surprised if its the engine ecu -

The 3rd RAV we looked at in Largs took about 4 hours to figure out

[Grizzly Adams]

Had an auto alarm friend of mine check the Rav out. It appears to have a dealer fitted alarm, and a factory fitted immobiliser. He can't find any faults. although he admits he hasn't been able to get right into the system.

Can anyone tell me how to re-sync the key please. Got to be easier than taking the immobiliser off if I don't need to.

Lot's of posts on here about it, but can't find anything really relevant, and I only have one key, the one we've been using for the last 6 years.

Thanks

Griz

[bothwell_buyer]

Had an auto alarm friend of mine check the Rav out. It appears to have a dealer fitted alarm, and a factory fitted immobiliser. He can't find any faults. although he admits he hasn't been able to get right into the system.

Can anyone tell me how to re-sync the key please. Got to be easier than taking the immobiliser off if I don't need to.

Lot's of posts on here about it, but can't find anything really relevant, and I only have one key, the one we've been using for the last 6 years.

Thanks

Griz

far as I know, the stuff was fitted when imported to UK. The 2 interlink.

The trick is to estanblish where the wiring is split on the ignition and ecu feeds/returns. I found on 1 that it was at the loom on the right kick plate down by the drivers feet where there are some fuses nearby. I had to trace the cables from the immobiliser ecu across the underneath of the dash - the cables are traceable as to where they all go - like to the sensors etc.

If the lecky can't find it, do you have a Jap car specilaist nearby as they would probably know.

[Grizzly Adams]

Hi Bothy, well the leccy almost sussed it without realising. What he did was remove the immobiliser box, and now the car will start but not keep running ie will run as long as the key is turned. I have had this on a couple of cars before and it's been a burned out fuel pump relay. Ran a live feed to the pump and it was just the same, so it's not that sadly. I found a post on this forum of how to sync, ie disconnect Battery, insert key and turn ign on, reconnect Battery, viola!

Tried that last night but the Rav's Battery is flat and I couldn't get the bonnet open on my Volvo to jump start it. Curses. Another job for the weekend. I am hopeful that re-syncing the key will cure it. I have proved that the immobiliser is at fault. Interestingly, all the wires into the immobiliser look like thet have has scotchlocks on them in the past, and they are all taped up.

Thanks

Phil

[bothwell_buyer]

Hi Bothy, well the leccy almost sussed it without realising. What he did was remove the immobiliser box, and now the car will start but not keep running ie will run as long as the key is turned. I have had this on a couple of cars before and it's been a burned out fuel pump relay. Ran a live feed to the pump and it was just the same, so it's not that sadly. I found a post on this forum of how to sync, ie disconnect battery, insert key and turn ign on, reconnect battery, viola!

Tried that last night but the Rav's battery is flat and I couldn't get the bonnet open on my Volvo to jump start it. Curses. Another job for the weekend. I am hopeful that re-syncing the key will cure it. I have proved that the immobiliser is at fault. Interestingly, all the wires into the immobiliser look like thet have has scotchlocks on them in the past, and they are all taped up.

Thanks

Phil

the best way is to get rid of the thing and install a new device if your worried about theft. Good luck - just the thing for passing a bank holiday weekend!

[Grizzly Adams]

So sorry to bore you further folks, but believe me you can't be more bored than I am. I am stuck.

There is little doubt that the key has gone out of sync with the immobiliser. Rav will turn over and fire with the immobiliser disconnected, but there are lots of wires, so little chance of it not needing some connections somewhere. Had a lucky guess at cutting the permanent earth to the immobiliser, now the car will turn over and start with the immobiliser connected having heeded Bothy's wise words about switched earths. All I need to do is suss out why the engine will only fire but not run. I am presuming the ecu is cutting the injectors but I don't know why. The fuel pump is running fine, and runs on after the engine has stopped. I believe the ecu is waiting for a signal from something, but what?

Some nice man quoted me £270 to come out and reprogramme my key. (I said I'd let him know)

Thanks again,

Griz

[bothwell_buyer]

So sorry to bore you further folks, but believe me you can't be more bored than I am. I am stuck.

There is little doubt that the key has gone out of sync with the immobiliser. Rav will turn over and fire with the immobiliser disconnected, but there are lots of wires, so little chance of it not needing some connections somewhere. Had a lucky guess at cutting the permanent earth to the immobiliser, now the car will turn over and start with the immobiliser connected having heeded Bothy's wise words about switched earths. All I need to do is suss out why the engine will only fire but not run. I am presuming the ecu is cutting the injectors but I don't know why. The fuel pump is running fine, and runs on after the engine has stopped. I believe the ecu is waiting for a signal from something, but what?

Some nice man quoted me £270 to come out and reprogramme my key. (I said I'd let him know)

Thanks again,

Griz

I'm sure this happened on the one I worked on in Largs. We found a wire split in by the fuses on the right side of the drivers feet. On 2 of the RAVs, I have removed the immobiliser box entirely. Its a shame you're way down south otherwise we could compare the wiring. Could be another circuit needing to be joined up without going through the immobiliser?

[Grizzly Adams]

Update.

well, the Bank holiday weekend came and went with me dividing my time between trawling t'inerweb for clues, and cutting and joining wires. I have now spoken to most people in the UK and their wives and dogs in my search for "the answer".

Have spoken to many ecu repairers who get twitchy immediately when you mention "Toyota" and answer "we can't do Toyota mate!". I've spoken to my local-ish dealer who remembers the last one they did worked out to about £1300. BUT, he recommended me to try a man called Danny in Reading. Danny says that in the 10 years he's being doing Toyotas he has never had a key fail. Danny says he can pop over and cut a key and sync it for me for £70 but reckons it will be a waste of money, and the only way to be sure is to buy an ecu, immobiliser ecu and a key set from a breakers. I have located one in a scrappy up north which they will part with for £250. At the suggestion of my wife I punched in the Toyota part number for the ecu, and found a firm up north who not only list the ecu, but will hire you one to try out for a reasonable fee. I am waiting til tomorrow to find out if they can supply me one with the immobiliser and key. When I have finished sifting through all available info I can decide which way to go.

Sorry Bothy, but I have yet to find anyone else to tell me that they CAN be bypassed, let alone how. I did find 2 wires as you said in the driver footwell that were "spliced". I bravely connected them together and the wipers came on!!!! I think the cars you had success with perhaps were a bit earlier. I think the immobiliser on my car is a serious bit of kit. Seems like the ecu will override any attempt to run without the immobiliser. But as Ester Rantzen used to say....

Unless of course, YOU know different.

Regards

Grizzly (still)

[bothwell_buyer]

still don't think its the ecu but if you can borrow one.....

I would still get rid of the immobilser - a Jap car specialist should be able to do this in a couple of hours..... if you get a chance to post up a pic of the immobilser fob/key thing, I could ask my local guys. Or pm me and I'll send you my email if its easier

[Grizzly Adams]

Just read Vashty's post with interest. So the keys do mess up from time to time then. That is well worth knowing. I am still stuck off road with no obvious way forward. I was going to buy the ecus and keyset from the breaker up north, but I asked them to check the part numbers and the ecu they had was from a manual so not compatible. Good job I checked.

Grizzo

[Grizzly Adams]

Deep joy, sorted at last.

After so many questions, and so many replies, all of which valid in their own circumstances I'm sure, I decided to stick with my gut feelings and replace the ecu, immobiliser ecu and lockset. Found one at a breaker in Birmingham after a long search, and as if by magic, after 5 weeks my Rav is a runner again, just in time for it's Mot. Just exactly what had gone wrong I will probably never know, I'm not going to start putting old parts back and risking the transponder code going wrong again. The lockset I have just bought has barrels for the doors which have a different key to the ignition barrel. Perhaps the donor car had had the same problem as I had. One thing for sure is that I will be getting 2 new keys cut. I imagine that I can get keys cut to match the old ignition barrel, but get the chips coded with the code from the replacement key.

thanks for all your help.

See you again,

Griz