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bobbins

Original Poster:

1,413 posts

236 months

Thursday 17th November 2011
quotequote all
After two weeks sans Cerb I'm enjoying the benefits of a new and improved beast when I decide to pop in and see robsco. After a few minutes' banter I bid him farewell and make to leave and, on pressing the black button - nothing.

After an hour or so of pulling various fuses, trying a jump start and a booster pack, it looks like only the AA can save the day when suddenly it just fires up at about the 20th time of asking, like nothing happened.

I've had three or four stops since and it's fired up again good as gold each time. God knows what the gremlin was* - but gotta love these cars eh? They're almost human. I figured it was just letting me know who the boss is after a bit of time apart. Anyway, it's back in the garage now after a fantastic hoon - on the trickle charger.

Thanks again for the help Rob - as I said, couldn't have happened in a better place on a better day really.

  • = happy to hear anyone's suggestions, for future reference smile

ukkid35

6,411 posts

202 months

Thursday 17th November 2011
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Do you hear the Fuel Pump run? Does the Solenoid click? Or do you really mean nothing at all?

scotty_d

6,795 posts

223 months

Thursday 17th November 2011
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Immob mine has been doing this all summer like took 2-3 times some times to fire up and now totally dead not enough V getting to the starter.

bobbins

Original Poster:

1,413 posts

236 months

Thursday 17th November 2011
quotequote all
Yep, fuel pump primes but no starter motor turning. Did the AJP have the same hot start problem the RV8 had?

Did think it might have been the battery but the fact it was well conditioned prior to recent work, coupled with the fact it suddenly sprung into life, makes me think it's not that.

bobbins

Original Poster:

1,413 posts

236 months

Thursday 17th November 2011
quotequote all
Cheers for that Scotty. I didn't have the immob key when it happened but wished I had - did it get things going when you had your problems?

C3BER

4,714 posts

252 months

Thursday 17th November 2011
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Ever since Robsco touched that silver key things have been going wrong!! hehe

bobbins

Original Poster:

1,413 posts

236 months

Thursday 17th November 2011
quotequote all
He did try to sell fiddling with it to me this afternoon but I resisted smile

scotty_d

6,795 posts

223 months

Thursday 17th November 2011
quotequote all
No nothing got mine going i need to phone Mr baker and get him to send me a new unit. I read on here how when it fails it only sends 9v to the starter i could here a very small click but it would not crank the engine. The fuel pump would prime fine just the cranking side of things is failing/failed.

DAVEY DEE

647 posts

183 months

Thursday 17th November 2011
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C3BER said:
Ever since Robsco touched that silver key things have been going wrong!! hehe
We did warn him! nono

robsco

7,875 posts

205 months

Thursday 17th November 2011
quotequote all
DAVEY DEE said:
C3BER said:
Ever since Robsco touched that silver key things have been going wrong!! hehe
We did warn him! nono
I suggested trying the silver key to Simon earlier on and he gave a look that nearly turned me to stone. hehe

It really is a mystery, we'd been messing about for a good hour or more when she finally just started up as though nothing had happened. Fuel pump was priming, starter wasn't even attempting to start the car so surely that leads to immobiliser as the potential cause?

Good to see you earlier Si, the old girl looks better than ever.

a1rak

556 posts

212 months

Thursday 17th November 2011
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My immobiliser packed up so I by passed it but on my 4.5 2001 cerb it is not the starter that is immobilsed. Its the factory meta system and has a 2 circuit immobilser that takes out the fuel pump and the ECU. The starter is not immobilised. It might be different on other models and years but my guess would be a faulty starter motor.

ridds

8,372 posts

273 months

Thursday 17th November 2011
quotequote all
Common issue, voltage drop or something like that through the starter circuit.

The voltage supplied by the starter circuit isn't great enough to energise the solenoid sufficiently. People have fitted an additional relay to allow a greater voltage to the solenoid.

Hence holding the button for LOOOOOONG time seems to get it to work.

TVdinneR

240 posts

179 months

Thursday 17th November 2011
quotequote all
Hi
There appear to be numerous cases of this happening. Reason I know is it happened to my sons 1998 4.5.
We scoured the forums and the consensus seemed to be that the starter circuit within the immobiliser goes AWOL.
We proceeded to bypass that particular circuit leaving both the ignition(ECU) and fuel pump circuits intact.
We wired in a hidden switch allowing the starter circuit to be switched between bypass and non-bypass.
Have never had the problem again.
Now I know this doesn't fully rectify the problem but it does the job meantime.
The only difference now is that if you attempt to start the car after that initial 15 secs the starter will crank the engine but there's no way it's gonna start as the ignition(ECU) and fuel pump are still immobilised.
I found out purely by chance that the immobiliser on my 4.2 had been completely bypassed ie no circuits immobilised.eek
I guessed someone in the past had the above problem and just bypassed the whole thing.
I have since wired the immobiliser back up as per above, also with a hidden switch, and everything works great.


Edited by TVdinneR on Friday 18th November 08:25

bobbins

Original Poster:

1,413 posts

236 months

Friday 18th November 2011
quotequote all
Useful stuff.

Hard to argue with the immobiliser theory, particularly after the last post. That and the fact the battery isn't that old and has been pretty well conditioned. I've had flats before and there was none of the associated carnage they wreak, although I did reset the alarm using the meta fob just to rule it out.

Ridds, Rob reminded me about keeping the black button pressed but after giving it a blast for a minute or so a couple of times we gave up on that.

I've added the immobiliser key to my key ring, so hopefully this will give me more of a chance if I don't get to the bottom of it in the meantime, or if it does it so infrequently as not to be a real concern.

Thanks again all.

TVdinneR

240 posts

179 months

Friday 18th November 2011
quotequote all
The symptoms we were getting were that you could approach the car, disarm/open the car with the remote fob and, assuming your within the 15 secs or so, push the black button, hear the fuel pump energise then........nowt, no clicking, no cranking, nothing!
This was becoming more and more frequent. You wouldn`t have a clue when and where this would happen.
Sometimes we could still be sitting there 20 mins later still trying then for no apparent reason it bangs into life.
The sheer uncertainty of the thing was a real pita, not to mention downright embarrassing, depending on when it decided not to start.

cerbera8

205 posts

313 months

Friday 18th November 2011
quotequote all
If the immobiliser is re-setting with the key but not the Remote key fob then I suggest you check the connection to the immobiliser and spray the connections with a little contact cleaner. Access gained through helmet holder. Sorted mine.

bobbins

Original Poster:

1,413 posts

236 months

Friday 18th November 2011
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Those were the exact symptoms TVDinneR. And thanks Cerbera8, will give it a shot.

Tanguero

4,535 posts

230 months

Friday 18th November 2011
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Replacing the immobiliser isn't particularly difficult. They were still available last time I looked.

N4 FTW

627 posts

214 months

Wednesday 23rd November 2011
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ridds said:
Common issue, voltage drop or something like that through the starter circuit.

The voltage supplied by the starter circuit isn't great enough to energise the solenoid sufficiently. People have fitted an additional relay to allow a greater voltage to the solenoid.

Hence holding the button for LOOOOOONG time seems to get it to work.
Hi Ridds, do you have any more information regarding where the additional relay would go please? (sorry for the potentially n00b question!)

Thanks!

Tanguero

4,535 posts

230 months

Wednesday 23rd November 2011
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As a quick fix you can use a relay which takes a feed from the big fuse and sends it to the starter solenoid, using the existing solenoid feed to switch it. Cable tie it in the V behind the coil packs.

The proper fix is to replace the immobiliser.